Water-Cooled Scroll Compressor Chillers

Transcription

1 Installation, Operation and Maintenance Manual IOMM WGZ-1 Group: Chiller Part Number: Effective: October 2004 Supercedes: IOMM WGZ Water-Cooled Scroll Compressor Chillers WGZ 030AW To WGZ 100AW, Packaged Water-Cooled Chiller WGZ 030AA To WGZ 100AA, Chiller with Remote Condenser 30 to 100 Tons, 105 to 350 kw R-22, Hz

2 Table of Contents Introduction...3 General Description...3 Nomenclature...3 Inspection...3 Installation...4 Vibration Isolators...6 Water Piping...9 Flow Switch...11 Glycol Solutions...12 Condenser Water Piping...13 Water Pressure Drop...14 Refrigerant Piping...17 Unit with Remote Condenser...17 Factory-Mounted Condenser...20 Dimensional Data...21 Physical Data...26 AW Water-Cooled...26 AA Remote Condenser...28 Operating Limits...29 Components...29 Wiring...30 Unit Configuration...31 Electrical Data...32 Field Wiring Diagrams...39 Control Panel Layout...41 Motor Protection Module...41 Start-Up and Shutdown...42 Pre Start-up...42 Start-up...42 Weekend or Temporary Shutdown...43 Start-up after Temporary Shutdown...43 Extended Shutdown...43 Start-up after Extended Shutdown...44 Sequence of Operation Standard MicroTech II Controller. 47 General Description...47 Setpoints...50 Equipment Protection (Shutdown) Alarms.51 Limit Alarms...52 Staging Parameters...54 Capacity Overrides...54 Digital Output Control...55 Analog Output Control...56 Using the Controller...58 Menu Screens... Menu Descriptions...61 Optional Controls Phase/Voltage Monitor (Optional)...75 Hot Gas Bypass (Optional)...75 System Maintenance General...76 Electrical Terminals...77 Compressor Lubrication...77 Sight glass and Moisture Indicator...77 Crankcase Heaters...77 Maintenance Schedule System Service Troubleshooting Chart...81 Warranty Statement Our facility is ISO Certified "McQuay" is a registered trademark of McQuay International 2003 McQuay International Illustrations and data cover McQuay International products at the time of publication and we reserve the right to make changes in design and construction at anytime without notice. 2 WGZ 030A through 100A IOMM WGZ-1

3 Introduction General Description McQuay Type WGZ water chillers are designed for indoor installations and are available with watercooled condensers (Model AW), or arranged for use with remote air-cooled or evaporative condensers (Model AA). Each water-cooled unit is completely assembled and factory wired before evacuation, charging and testing. They consist of hermetic scroll compressors, brazed-plate evaporator, watercooled condenser (WGZ-AW), and complete refrigerant piping. Units manufactured for use with remote condensers (Models WGZ-AA) have all refrigerant specialties factory-mounted and connection points for refrigerant discharge and liquid lines. Liquid line components that are included are manual liquid line shutoff valves, charging valves, filterdriers, liquid line solenoid valves, sight glass/moisture indicators, and thermal expansion valves. Other features include compressor crankcase heaters, and a MicroTech II microprocessor controller. The electrical control center includes all equipment protection and operating controls necessary for dependable automatic operation. The compressors are not fused as standard, but can be protected by optional circuit breakers or fuses, or can rely on a field-installed, fused disconnect switch for protection. Nomenclature W G Z A W Water-Cooled Condensing Global Scroll Compressor W = Water-Cooled Condenser A = Unit Less Condenser Design Vintage Nominal Capacity (Tons) Inspection When the equipment is received, all items should be carefully checked against the bill of lading to be sure of a complete shipment. All units must be carefully inspected for damage upon arrival. All shipping damage must be reported to the carrier and a claim must be filed with the carrier. The unit serial plate should be checked before unloading the unit to be sure that it agrees with the power supply available. Physical damage to unit after acceptance is not the responsibility of McQuay. Note: Unit shipping and operating weights are given in the physical data tables beginning on page 26. IOMM WGZ-1 WGZ 030A through 100A 3

4 Installation Note: Installation and maintenance are to be performed only by qualified personnel who are familiar with local codes and regulations, and experienced with this type of equipment. Handling WARNING Avoid contact with sharp edges. Personal injury can result. Every model WGZ-AW water chiller with water-cooled condensers is shipped with a full refrigerant charge. For shipment, the charge is contained in the condenser and is isolated by the condenser liquid shutoff valve and the compressor discharge valve common to a pair of compressors. A holding charge is supplied in remote condenser models, WGZ-AA. The operating charge must be field supplied and charged. WARNING If the unit has been damaged, allowing the refrigerant to escape, there can be danger of suffocation in the equipment area since the refrigerant will displace the air. Be sure to review Environmental Protection Agency (EPA) requirements if damage occurred. Avoid exposing an open flame to the refrigerant. Moving the Unit Some means such as dollies or skids must be field furnished to protect the unit from accidental damage and to permit easy handling and moving. Figure 1, Lifting the Unit (2) 2 Lifting Holes Removable Lifting Bar Never put the weight of the unit against the control box. It is recommended that all moving and handling be performed with skids or dollies under the unit when possible and that they not be removed until the unit is in the final location. In moving, always apply pressure to the base on the skids only and not to the piping or other components. A long bar will help move the unit easily. Avoid dropping the unit at the end of the roll. 4 WGZ 030A through 100A IOMM WGZ-1

5 If the unit must be hoisted, lift the unit from the removable lifting arms factory-bolted to each end of the unit adjacent to the tube sheet by attaching cables or chains to the end of the arms. A spreader bar must be used to protect the piping, control panel and other areas of the chiller (see Figure 1). The arms should be removed and discarded after use. Do not attach slings to piping or equipment. Do not attempt to lift the unit by lifting points mounted on the compressors. They are for lifting only the compressor should one need to be removed from the unit. Move unit in the upright horizontal position at all times. Set unit down gently when lowering from the truck or rollers. Table 1, Lifting Loads Package Units (lbs. Model L1 L2 L3 L4 Shipping Weight Less Condenser Units (lbs) Shipping L1 L2 L3 L4 Weight WGZ WGZ WGZ WGZ WGZ WGZ WGZ WGZ WGZ WGZ WGZ Location WGZ chillers are designed for indoor application and must be located in an area where the surrounding ambient temperature is 40 F (4 C) or above. A good rule of thumb is to place units where ambient temperatures are at least 5 F (3 C) above the leaving water temperature. Because of the electrical control devices, the units should not be exposed to the weather. A plastic cover over the control box is supplied as temporary protection during shipment. A reasonably level and sufficiently strong floor is required for the water chiller. If necessary, additional structural members should be provided to transfer the weight of the unit to the nearest beams. Note: Unit shipping and operating weights are given in Table 1 and in the physical data tables beginning on page 26. Space Requirements for Connections and Servicing The chilled water and condenser water (on units with a water-cooled condenser) piping enters and leaves the unit from the right side when looking at the control panel. Left-hand condenser connections are an option. A clearance of at least 3 feet (1219 mm), or more if codes require, should be provided beyond this piping and on all other sides and ends of the unit for general servicing or for changing the compressors, if it ever becomes necessary. On units equipped with a water-cooled condenser (Type WGZ-AW) clearance should also be provided for cleaning or removal of condenser tubes on one end of the unit. The clearance for cleaning depends on the type of apparatus used, but can be as much as the length of the condenser (10 feet, 3050 mm). Tube replacement requires the tube length of 10 feet (3050 mm) plus one to two feet of workspace. This space can often be provided through a doorway or other aperture. Placing the Unit The small amount of vibration normally encountered with the water chiller makes this unit particularly desirable for basement or ground floor installations where the unit can be mounted directly to the floor. The floor construction should be such that the unit will not affect the building structure, or transmit noise and vibration into the structure. IOMM WGZ-1 WGZ 030A through 100A 5

6 Vibration Isolators It is recommended that isolators be used on all upper level installations or in areas where vibration transmission is a consideration. Figure 2, Isolator Locations 4 1 LB LF RB FRF 3 2 Water Connections Transfer the unit as indicated under Moving the Unit. In all cases, set the unit in place and level with a spirit level. When spring-type isolators are required, install springs running under the main unit supports. The unit should be set initially on Control Panel shims or blocks at the listed spring free height. When all piping, wiring, flushing, charging, etc., is completed, the springs are adjusted upward to loosen the blocks or shims that are then removed. A rubber anti-skid pad should be used under isolators if hold-down bolts are not used. Installation of spring isolators requires flexible piping connections and at least three feet of flexible electrical conduit to avoid straining the piping and transmitting vibration and noise. Table 2, Weights & Mountings ARRANGEMENT WGZ-AW, WITH WATER-COOLED CONDENSERS Unit Opr. Wt. Corner Weight Lbs (kg) Neoprene-In-Shear Mountings Spring-Flex Mountings Size Lbs. (kg) (1219) 27 (1250) 2866 (1298) 2966 (1344) 3058 (1385) 3213 (1455) 3809 (1725) 4025 (1823) 4289 (1943) 4484 (2031) 4627 (2096) 589 (267) 599 (271) 616 (279) 632 (286) 644 (292) 688 (312) 853 (386) 916 (415) 958 (434) 974 (441) 989 (448) 648 (294) 661 (299) 682 (309) 702 (318) 718 (325) 772 (350) 959 (435) 1033 (468) 1082 (490) 1103 (500) 1121 (508) 692 (314) 713 (323) 744 (337) 773 (350) 802 (363) 826 (374) 940 (426) 975 (442) 1056 (478) 1129 (511) 1179 (534) 762 (345) 787 (356) 824 (373) 8 (389) 894 (405) 927 (420) 1057 (479) 1100 (498) 1193 (540) 1278 (579) 1337 (6) RP-4 Black RP-4 Black RP-4 Black RP-4 Black RP-4 Black RP-4 Black RP-4 Black RP-4 Black Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange Orange White White White White White White CP-2 CP-2 6 WGZ 030A through 100A IOMM WGZ-1

7 Unit Size ARRANGEMENT WGZ-AA, FOR REMOTE CONDENSER Opr. Wt. Corner Weight Lbs (kg) Neoprene-In-Shear Mountings Spring-Flex Mountings Lbs. (kg) (979) 2204 (998) 2257 (1022) 2329 (1055) 2370 (1074) 2505 (1135) 2771 (1255) 2942 (1333) 3154 (1429) 3271 (1482) 3346 (1516) 468 (212) 472 (214) 477 (216) 487 (220) 488 (221) 526 (238) 619 (280) 672 (304) 702 (318) 700 (317) 697 (316) 502 (227) 507 (230) 514 (233) 526 (238) 528 (239) 578 (262) 674 (305) 736 (333) 771 (349) 771 (349) 773 (350) (2) 590 (267) 9 (276) 633 (287) 650 (295) 668 (303) 707 (320) 732 (332) 801 (363) 857 (388) 890 (403) 616 (279) 634 (287) 657 (297) 684 (310) 704 (319) 734 (332) 770 (349) 801 (363) 880 (399) 944 (427) 987 (447) Purple Purple Purple Purple Purple Purple Purple Orange Orange Purple Orange Orange Purple Orange Orange Purple Orange Orange Purple Orange Orange Purple Orange Orange Orange Orange Orange Orange Orange Orange Orange Table 3, Spring Flex Isolators Housing CP-2 Spring Color Red Purple Orange White Max. Load Each Lbs. (kg) 450 (204) 0 (272) 750 (340) 900 (408) 1100 (498) 1300 (589) 1800 (815) Defl. In. (mm) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) Dimensions In. (mm) A B C D E 7.5 (190.5) 7.5 (190.5) 7.5 (190.5) 7.5 (190.5) 7.5 (190.5) 7.5 (190.5) 10.2 (259.1) 6.0 (152.4) 6.0 (152.4) 6.0 (152.4) 6.0 (152.4) 6.0 (152.4) 6.0 (152.4) 9.0 (228.6) 4.7 (119.4) 4.7 (119.4) 4.7 (119.4) 4.7 (119.4) 4.7 (119.4) 4.7 (119.4) 7.7 (195.6) NOTE: housing contains one spring. CP-2 housing contains two identical springs. 2.7 (68.6) 2.7 (68.6) 2.7 (68.6) 2.7 (68.6) 2.7 (68.6) 2.7 (68.6) 2.7 (68.6) 5.5 (139.7) 5.5 (139.7) 5.5 (139.7) 5.5 (139.7) 5.5 (139.7) 5.5 (139.7) 5.75 (146.0) Housing Part Number Spring Part Number B A B A B A B A B A B A B-00 (2) A-00 IOMM WGZ-1 WGZ 030A through 100A 7

8 Table 4, Neoprene-in-Shear Isolators Type Max. Load Each Lbs. (kg) Defl. In. (mm) (339) (6.4) (63.5) (498) (6.4) (63.5) RP-4 Black (679) (6.4) (95.3) RP-4 Red (1019) (6.4) (95.3) Note (1) "D" is the mounting hole diameter. Dimensions In. (mm) A B C D (1) E H L W 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 0.5 (12.7) 4.1 (104.1) 4.1 (104.1) 5.0 (127.0) 5.0 (127.0) 0.56 (14.2) 0.56 (14.2) 0.56 (14.2) 0.56 (14.2) 0.25 (6.4) 0.25 (6.4) 0.25 (6.4) 0.25 (6.4) 1.75 (44.4) 1.75 (44.4) 1.6 (41.1) 1.6 (41.1) 5.5 (165) 5.5 (165) 6.5 (165.1) 6.5 (165.1) McQuay Part Number 3.4 (85.7) A (85.7) A (116.8) A (116.8) A-01 Figure 3, Spring Flex Mountings Figure 4, Single Neoprene-in-Shear Mounting 8 WGZ 030A through 100A IOMM WGZ-1

9 Water Piping General Due to the variety of piping practices, it is advisable to follow the recommendations of local authorities for code compliance. They can supply the installer with the proper building and safety codes required for a safe and proper installation. Basically, the piping should be designed with a minimum number of bends and changes in elevation to keep system cost down and performance up. Other piping design considerations include: 1. All piping should be installed and supported to prevent the chiller connections from bearing any strain or weight of the system piping. 2. Vibration eliminators to reduce vibration and noise transmission to the building. 3. Shutoff valves to isolate the unit from the piping system during unit servicing. 4. Manual or automatic air vent valves at the high points of the system. Drains should be placed at the lowest points in the system. 5. Some means of maintaining adequate system water pressure (e.g., expansion tank or regulating valve). 6. Temperature and pressure indicators located within 3 feet (0.9 meters) of the inlet and outlet of the vessels to aid in unit servicing. 7. A strainer or some means of removing foreign matter from the water before it enters the pump is recommended. It should be placed far enough upstream to prevent cavitation at the pump inlet (consult pump manufacturer for recommendations). The use of a strainer will prolong pump life and thus maintain system performance. Important Note A cleanable 40-mesh strainer must also be placed in the water line just prior to the inlet of the evaporator. This will aid in preventing foreign material from entering and decreasing the performance of the evaporator. 8. If the unit is used as a replacement chiller on a previously existing piping system, the system should be thoroughly flushed prior to unit installation. Regular water analysis and chemical water treatment on the evaporator and condenser is recommended immediately upon equipment start-up. 9. In the event glycol is added to the water system, as an afterthought for freeze protection, recognize that the refrigerant suction pressure will be lower, cooling performance less, and water side pressure drop will be higher. If the percentage of glycol is large, or if propylene glycol is used instead of ethylene glycol, the added pressure drop and loss of performance could be substantial. Reset the freezestat and low leaving water alarm temperatures. The freezestat is factory set to default at 36 F (2.2 C). Reset the freezestat setting to approximately 4 to 5 F (2.3 to 2.8 C) below the leaving chilled water setpoint temperature. See the section titled Glycol Solutions for additional information concerning the use of glycol. 10. A preliminary leak check of the water piping should be made before filling the system. Note: A water flow switch or pressure differential switch must be mounted in the evaporator outlet water line to signal that there is water flow before the unit will start. IOMM WGZ-1 WGZ 030A through 100A 9

10 Figure 5, Typical Field Evaporator Water Piping Air Vent Strainer Inlet P Vibration Eliminators Isolation Valves Outlet Drain NOTE: Water piping must be supported independently from the unit. Flow Switch System Water Volume It is important to have adequate water volume in the system to provide an opportunity for the chiller to sense a load change, adjust to the change, and then stabilize. As the expected load change becomes more rapid, a greater water volume is needed. The system water volume is the total amount of water in the evaporator, air handling equipment, and associated piping. If the water volume is too low, operational problems can occur including rapid compressor cycling, rapid loading and unloading of compressors, erratic refrigerant flow in the chiller, improper motor cooling, shortened equipment life and other undesirable occurrences. For normal comfort cooling applications where the cooling load changes relatively slowly, we recommend a minimum system volume of four minutes times the flow rate (GPM). For example, if the design chiller flow rate is 120 gpm, we recommend a minimum system volume of 480 gallons (120 gpm x 4 minutes). For process applications where the cooling load can change rapidly, additional system water volume is needed. A process example would be the quenching of hot metal objects. The load would be very stable until the hot metal is dipped into the water tank. Then, the load would increase drastically. Since there are many other factors that can influence performance, systems can successfully operate below these suggestions. However, as the water volume decreases below these guidelines, the possibility of problems increases. Variable Chilled Water Flow Reducing chilled water flow in proportion to load can reduce total system power consumption. Certain restrictions apply to the amount and rate of flow change. The rate of flow change should be a maximum of 10 percent of the change, per minute. Do not reduce flow lower than the minimum flows listed in the pressure drop data on page 15. Chilled Water Piping The system water piping must be flushed thoroughly prior to making connections to the unit evaporator. It is required that a 1.0 mm (16 to 20 mesh) strainer be installed in the return water line before the inlet to the chiller. Lay out the water piping so the chilled water circulating pump discharges into the evaporator inlet. The return water line must be piped to the evaporator inlet connection and the supply water line must be piped to the evaporator outlet connection. If the evaporator water is piped in the reverse direction, a substantial decrease in capacity and efficiency of the unit will be experienced. A flow switch must be installed in the horizontal piping of the supply (evaporator outlet) water line to prove water flow before starting the unit. 10 WGZ 030A through 100A IOMM WGZ-1

11 Drain connections should be provided at all low points in the system to permit complete drainage of the system. Air vents should be located at the high points in the system to purge air out of the system. The evaporators are not equipped with vent or drain connections and provision must be made in the entering and leaving chilled water piping for venting and draining. Pressure gauges should be installed in the inlet and outlet water lines to the evaporator. Pressure drop through the evaporator should be measured to determine water flow from the flow/pressure drop curves on page 15. Vibration eliminators are recommended in both the supply and return water lines. Chilled water piping should be insulated to reduce heat loss and prevent condensation. Complete unit and system leak tests should be performed prior to insulating the water piping. Insulation with a vapor barrier would be the recommended type of insulation. If the vessel is insulated, the vent and drain connections must extend beyond the proposed insulation thickness for accessibility. Chillers not run in the winter should have their water systems thoroughly drained if subject to subfreezing temperatures. If the chiller operates year-round, or if the system is not drained for the winter, the chilled water piping exposed to sub-freezing ambient temperatures should be protected against freezing by wrapping the lines with a heater cable. In addition, an adequate percentage of glycol should be added to the system to further protect the system during low ambient temperature periods. It should be noted that water piping that has been left drained is subject to more corrosion than if filled with water. Use of a Vapor Corrosion Inhibitor (VCI) or some other protection should be considered. Chilled Water Sensor Figure 6, Thermostat Well Location Suction Circuit #1 Suction Circuit #2 Leaving Chilled Water Sensor Liquid Circuit #2 Liquid Circuit #1 The chilled water sensor is factory installed in the leaving water connection on the evaporator. Care should be taken not to damage the sensor cable or lead wires when working around the unit. It is also advisable to check the lead wire before running the unit to be sure that it is firmly anchored and not rubbing on the frame or any other component. If the sensor is ever removed from the well for servicing, care must be taken to not wipe off the heat-conducting compound supplied in the well. CAUTION The thermostat bulb should not be exposed to water temperatures above 125 F (51.7 C) since this will damage it. Flow Switch A water flow switch must be mounted in the leaving evaporator and condenser water line to prove adequate water flow before the unit can start. This will safeguard against slugging the compressors on start-up. It also serves to shut down the unit in the event that water flow is interrupted to guard against evaporator freeze-up. A flow switch is available from McQuay under part number It is a paddle type switch and adaptable to any pipe size from 1 in. (25 mm) to 6 in. (152 mm) nominal. Certain minimum flow rates are required to close the switch and are listed in Table 5. Electrical connections in the unit control center should be made at terminals 33 and 43 (chilled water) and 41 and 53 (condenser water). The normally open contacts of the flow switch should be wired between these two terminals. There is also a set of normally closed contacts on the switch that could be used for an indicator light or an alarm to indicate when a no flow condition exists. IOMM WGZ-1 WGZ 030A through 100A 11

12 1. Apply pipe sealing compound to only the threads of the switch and screw unit into 1 in. (25 mm) reducing tee. The flow arrow must be pointed in the correct direction. 2. Piping should provide a straight length before and after the flow switch of at least five times the pipe diameter without any valves, elbows, or other flow restricting elements. 3. Trim flow switch paddle if needed to fit the pipe diameter. Make sure paddle does not hang up in pipe. CAUTION Make sure the arrow on the side of the switch is pointed in the direction of flow. The flow switch is designed to handle the control voltage and should be connected according to the wiring diagram (see wiring diagram inside control box door). Incorrect installation will cause improper operation and possible evaporator damage. Table 5, Flow Switch Flow Rates Pipe Size inch 2 2 1/ mm (125) (150) gpm Flow Minimum Lpm Adjustment No gpm Flow Lpm gpm Flow Maximum Lpm Adjustment No gpm Flow Lpm Glycol Solutions When using a glycol solution, the chiller capacity, flow rate, evaporator pressure drop, and chiller power input can be calculated using the following formulas and reference to Table 6 for ethylene glycol and Table 7 for propylene glycol. 1. Capacity, Capacity is reduced compared to that with plain water. To find the reduced value, multiply the chiller s capacity when using water by the capacity correction factor C to find the chiller s capacity when using glycol. 2. Flow, To determine evaporator gpm (or T) knowing T (or gpm) and capacity: x Glycol Capacity Glycol GPM = 24 x Flow Correction G From Tables T For Metric Applications -- Determine evaporator lps (or T) knowing T (or lps) and kw: kw Glycol Lps = x Flow Correction G from Tables 4.18 x T 3. Pressure Drop, To determine glycol pressure drop through the cooler, enter the water pressure drop graph on page 15 at the actual glycol flow. Multiply the water pressure drop found there by P to obtain corrected glycol pressure drop. 4. Power, To determine glycol system kw, multiply the water system kw by factor K. Test coolant with a clean, accurate, glycol solution hydrometer (similar to that found in service stations) to determine the freezing point. Obtain percent glycol from the freezing point found in Table 6 or Table 7. On glycol applications the supplier normally recommends that a minimum of 25% solution by weight be used for protection against corrosion or the use of additional inhibitors. 12 WGZ 030A through 100A IOMM WGZ-1

13 Note: The effect of glycol in the condenser is negligible. As glycol increases in temperature, its characteristics have a tendency to mirror those of water. Therefore, for selection purposes, there is no derate in capacity for glycol in the condenser. Table 6, Ethylene Glycol Percent Freezing Point P (Pressure C (Capacity) K (Power) G (Flow) Glycol F C Drop) Table 7, Propylene Glycol Percent Freezing Point P (Pressure C (Capacity) K (Power) G (Flow) Glycol F C Drop) CAUTION Do not use automotive grade antifreeze. Industrial grade glycols must be used. Automotive antifreeze contains inhibitors which cause plating on copper tubes. The type and handling of glycol used must be consistent with local codes. Condenser Water Piping Arrange the condenser water so the water enters the bottom connection of the condenser. The condenser water will discharge from the top connection. Failing to arrange the condenser water as stated above will negatively affect the capacity and efficiency. Pressure gauges should be installed in the inlet and outlet water lines to the condenser. Pressure drop through the condenser should be measured to determine flow on the pressure drop/flow curves on page 16. Vibration eliminators are recommended in both the supply and return water lines. Water-cooled condensers can be piped for use with cooling towers, well water, or heat recovery applications. Cooling tower applications should be made with consideration of freeze protection and scaling problems. Contact the cooling tower manufacturer for equipment characteristics and limitations for the specific application. Head pressure control must be provided if the entering condenser water can fall below F. The WGZ condenser has two refrigerant circuits with a common condenser water circuit. This arrangement makes head pressure control with discharge pressure actuated control valves difficult. If for some reason the tower water temperature cannot be maintained at a F minimum, or when pond, lake, or well water that can fall below F (15 C) is used as the condensing medium, special discharge pressure control must be used. A water recirculating system with recirculating pump as shown in Figure 7 is recommended. This system also has the advantage of maintaining tube velocity to help prevent tube fouling. The pump should cycle with the chiller. IOMM WGZ-1 WGZ 030A through 100A 13

14 Figure 7, Recirculating Discharge Pressure Control System Circuit #1 Inlet Circuit #2 Inlet Temperature Control Valve Condenser Condenser Water Circuit #1 Outlet Circuit #2 Outlet Water Pressure Drop The vessel flow rates must fall between the minimum and maximum values shown on the appropriate evaporator and condenser curves. Flow rates below the minimum values shown will result in laminar flow that will reduce efficiency, cause erratic operation of the electronic expansion valve and could cause low temperature cutoffs. On the other hand, flow rates exceeding the maximum values shown can cause erosion in the evaporator. Measure the chilled water pressure drop through the evaporator at field-installed pressure taps. It is important not to include valves or strainers in these readings. 14 WGZ 030A through 100A IOMM WGZ-1

15 Figure 8, Evaporator Water Pressure Drop, WGZ 030A through 100A WGZ 045 WGZ 040 WGZ 050 WGZ 035 WGZ 055 WGZ 030 WGZ 100 WGZ 090 WGZ 0 WGZ 080 WGZ 070 Minimum Flow Nominal Flow Maximum Flow WGZ Model Flow Rate Pressure Drop Flow Rate Pressure Drop Flow Rate Pressure Drop gpm L/s Ft. kpa gpm L/s Ft. kpa gpm L/s Ft. kpa Note: Minimum, nominal, and maximum flows are at a 16 F, 10 F, and 6 F chilled water temperature range respectively, and at ARI tons. IOMM WGZ-1 WGZ 030A through 100A 15

16 Figure 9, Condenser Water Pressure Drop, WGZ 030AW through 100AW WGZ 035 WGZ 040 WGZ 045 WGZ 070 WGZ 080 WGZ 090 WGZ 030 WGZ 100 WGZ 055 WGZ 050 WGZ 0 WGZ Model Minimum Flow Nominal Flow Maximum Flow Flow Rate Pressure Drop Flow Rate Pressure Drop Flow Rate Pressure Drop gpm L/s Ft. kpa gpm L/s Ft. kpa gpm L/s Ft. kpa WGZ 030A through 100A IOMM WGZ-1

17 Refrigerant Piping Unit with Remote Condenser General For remote condenser application (WGZ-AA) such as air-cooled or evaporative condenser, the chillers are shipped with an R-22 holding charge. It is important that the unit be kept tightly closed until the remote condenser is installed, piped to the unit and the high side evacuated. Refrigerant piping, to and from the unit, should be sized and installed according to the latest ASHRAE Handbook. It is important that the unit piping be properly supported with sound and vibration isolation between tubing and hanger, and that the discharge lines be looped at the condenser and trapped at the compressor to prevent refrigerant and oil from draining into the compressors. Looping the discharge line also provides greater line flexibility. The discharge gas valves, liquid line solenoids, filter-driers, moisture indicators, and thermostatic expansion valves are all factory mounted as standard equipment with the water chiller. A liquid line shutoff valve must be added in the field on remote condenser units between the liquid line filter-drier and remote condenser. After the equipment is properly installed, leak tested, and evacuated, it can be charged with R-22, and run at design load conditions. Add charge until the liquid line sight glass is clear, with no bubbles flowing to the expansion valve. Total operating charge will depend on the air-cooled condenser used and volume of the refrigerant piping. Note: On the arrangement WGZ-AA units (units with remote condensers), the installer is required to record the refrigerant charge by stamping the total charge and the charge per circuit on the serial plate in the appropriate blocks provided for this purpose. The following discussion is intended for use as a general guide to the piping of air-cooled condensers. Discharge lines must be designed to handle oil properly and to protect the compressor from damage that can result from condensing liquid refrigerant in the line during shutdown. Total friction loss for discharge lines of 3 to 6 psi (20.7 to 41.4 kpa) is considered good design. Careful consideration must be given for sizing each section of piping to insure that gas velocities are sufficient at all operating conditions to carry oil. If the velocity in a vertical discharge riser is too low, considerable oil can collect in the riser and the horizontal header, causing the compressor to lose its oil and result in damage due to lack of lubrication. When the compressor load is increased, the oil that had collected during reduced loads can be carried as a slug through the system and back to the compressor, where a sudden increase of oil concentration can cause liquid slugging and damage to the compressor. Any horizontal run of discharge piping should be pitched away from the compressor approximately 1/8 inch (6.4 mm) per foot (meter) or more. This is necessary to move, by gravity, any oil lying in the header. Oil pockets must be avoided because oil needed in the compressor would collect at such points and the compressor crankcase can become starved. It is recommended that any discharge lines coming into a horizontal discharge header rise above the centerline of the discharge header. This is necessary to prevent any oil or condensed liquid from draining to the compressor heads when the compressor is not running. IOMM WGZ-1 WGZ 030A through 100A 17

18 In designing liquid lines, it is important that the liquid reach the expansion valve without flash gas since this gas will reduce the capacity of the valve. Because flashing can be caused by a pressure drop in the liquid line, the pressure losses due to friction and changes in static head should be kept to a minimum. A check valve must be installed in the liquid line in all applications where the ambient temperature can drop below the equipment room temperature. This prevents liquid migration to the condenser, helps maintain a supply of refrigerant in the liquid line for initial start-up, and keeps liquid line pressure high enough on off cycle to keep the expansion valve closed. On systems as described above, a relief valve or relief-type check valve, must be used in the liquid line as shown in piping systems (shown in Figure 11) to relieve dangerous hydraulic pressures that could be created as cool liquid refrigerant in the line between the check valve and the expansion or shutoff valve warms up. A relief device is also recommended in the hot gas piping at the condenser coil as shown in Figure 10 and Figure 11. Typical Arrangements Figure 10 illustrates a typical piping arrangement involving a remote air-cooled condenser located at a higher elevation than the compressor and receiver. This arrangement is commonly encountered when the air-cooled condenser is on a roof and the compressor and receiver are on grade level or in a basement equipment room. Notice, in both illustrations, that the hot gas line is looped at the bottom and top of the vertical run. This is done to prevent oil and condensed refrigerant from flowing back into the compressor and causing damage. The highest point in the discharge line should always be above the highest point in the condenser coil. It is advisable to include a purging vent at this point to extract non-condensables from the system. Figure 11 illustrates another very common application where the air-cooled condenser is located on essentially the same level as the compressor and receiver. The discharge line piping in this case is not too critical. The principal problem encountered with this arrangement is that there is frequently insufficient vertical distance to allow free drainage of liquid refrigerant from the condenser coil to the receiver. The receiver is used when it is desired to have refrigerant storage capacity, in addition to the pumpdown capability of the condenser. 18 WGZ 030A through 100A IOMM WGZ-1

19 Figure 10, Condenser Above Compressor and Receiver Relief Valve Check Valve (Preferred) Purge Valve Condenser Pitch Subcooler Discharge Line Preferred Relief Valve Subcooler (Vent to Outdoors Hook-up or to Condenser Side of Liquid Line Check Valve) To Evap. Receiver Bypass Receiver Check Valve Loop Figure 11, Condenser and Compressor on Same Level Condenser Subcooler Relief Valve Check Valve (Preferred) Pitch Check Valve Purge Valve Discharge Line Relief Valve (Vent to Outdoors or to Condenser Side of Liquid Line Check Valve) Preferred Subcooler Hook-up To Evap. Receiver Bypass Receiver Check Valve IOMM WGZ-1 WGZ 030A through 100A 19

20 Factory-Mounted Condenser Units with the standard water-cooled, factory-mounted condenser are provided with complete refrigerant piping and full operating refrigerant charge at the factory. There is a remote possibility on water-cooled units utilizing low temperature pond or river water as a condensing medium, and if the water valves leak, that the condenser and liquid line refrigerant temperature could drop below the equipment room temperature on the off cycle. This problem only arises during periods when cold water continues to circulate through the condenser and the unit remains off due to satisfied cooling load. If this condition occurs: 1. Cycle the condenser pump off with the unit. 2. Check the liquid line solenoid valve for proper operation. Relief Valve Piping The ANSI/ASHRAE Standard 15, Safety Standard for Refrigeration Systems, specifies that pressure relief valves on vessels containing Group 1 refrigerant (R-22) shall discharge to the atmosphere at a location not less than 15 feet (4.6 meters) above the adjoining ground level and not less than 20 feet (6.1 meters) from any window, ventilation opening or exit in any building. The piping must be provided with a rain cap at the outside terminating point and with a drain at the low point on the vent piping to prevent water buildup on the atmospheric side of the relief valve. In addition, a flexible pipe section should be installed in the line to eliminate any piping stress on the relief valve(s). The size of the discharge pipe from the pressure relief valve should not be less than the size of the pressure relief outlet. When two or more vessels are piped together, the common header and piping to the atmosphere should not be less than the sum of the area of each of the lines connected to the header. NOTE: Fittings should be provided to permit vent piping to be easily disconnected for inspection or replacement of the relief valve. Figure 12, Relief Valve Piping 20 WGZ 030A through 100A IOMM WGZ-1

21 Dimensional Data WGZ-AW Water-Cooled Figure 13, WGZ 030AW through WGZ 055AW Door Swing W Evaporator Recommended for Servicing H Y Z L A MicroTech II User Interface Evaporator Inlet Control Connection Outlet Condenser Outlet Inlet Power Connections (2).875" (22 mm) (4).875" (22 mm) Mounting Holes Relief Valves (1) Each End X WGZ Model Number Maximum Overall Dimensions in. (mm) Chiller Water Connection Victaulic, in. (mm) Condenser Water Connections Victaulic, in. (mm) Center of Gravity in. (mm) L W H Size A Size X Y Z (3406) (813) (1613) (76) (2394) (102) (1676) (698) (366) (3406) (813) (1613) (76) (2957) (102) (1684) (698) (366) (3406) (813) (1613) (76) (2991) (102) (1694) (696) (363) (3406) (813) (1613) (76) (3024) (102) (1704) (701) (363) (3406) (813) (1613) (76) (3058) (102) (1714) (696) (363) (3406) (813) (1613) (76) (3075) (102) (1687) (698) (361) IOMM WGZ-1 WGZ 030A through 100A 21

22 Figure 14, WGZ-0AW through WGZ-100AW Door Swing Clearance W Evaporator Recommended for Servicing H Y Z MicroTech II User Interface L A Control Connection Inlet Evaporator Outlet Condenser Outlet Inlet Power Connections (2).875" (22 mm) T (4).875" (22 mm) Diameter Mounting Holes Relief Valves (1) Each End X WGZ Model Number Maximum Overall Dimensions in. (mm) Chiller Water Connection Victaulic, in. (mm) Condenser Water Connections Victaulic, in. (mm) Center of Gravity in. (mm) L W H Size A Size T X Y Z (3663) (813) (1676) (76) (2978) (127) (280) (1628) (787) (354) (127) (3726) (813) (1676) (76) (3018) (306) (10) (813) (354) (3726) (813) (1676) (76) (3112) (127) (306) (1585) (831) (352) (3784) (813) (1676) (76) (3216) (127) (401) (1) (848) (352) (3784) (813) (1676) (76) (3274) (127) 9401) (1684) (841) (341) 22 WGZ 030A through 100A IOMM WGZ-1

23 WGZ-AA Remote Condenser Figure 15, Dimensions, WGZ 030AA WGZ 055AA Door Swing Clearance W Recommended for Servicing "G" Disch Conn "E" Liquid Conn H Y Z L A MicroTech II User Interface "G" Disch. System #2 "G" Disch. System #1 Control Connection Inlet Evaporator Outlet T B D C "E" Liquid System #2 "E" Liquid System # F Power Connections (2) (22 mm) (4) (22 mm) Mounting Holes WGZ Model Number Maximum Overall Dimensions in. (mm) X Chiller Water Connection Victaulic in. (mm) L W H Size A (3109) (813) (1613) (76) (2394) (3109) (813) (1613) (76) (2957) (3109) (813) (1613) (76) (2991) (3109) (813) (1613) (76) (3024) (3109) (813) (1613) (76) (3058) (3134) 32 (813) 63.5 (1613) 3 (76) (3075) Refrigerant Connections System #1 System #2 Connection Size Liquid F 67 (1702) 67 (1702) 67 (1702) 67 (1702) 67 (1702) 80.2 (2037) Disch. C 38.2 (970) 38.2 (970) 38.2 (970) 38.2 (970) 38.2 (970) 43.4 (1102) Liquid D 52 (1320) 52 (1320) 52 (1320) 52 (1320) 52 (1320) 38.6 (980) Disch. B 42.9 (1090) 42.9 (1090) 42.9 (1090) 42.9 (1090) 42.9 (1090) 39.5 (1003) Liquid E.875 (22).875 (22).875 (22).875 (22).875 (22).875 (22) (29) Center of Gravity in. (mm) Disch. G T X Y Z (29) (74) (1694) (792) (373) (29) (74) (1709) (795) (371) (29) (74) (1725) (800) (371) (29) (74) (1737) (805) (371) (29) (74) (1758) (810) (368) (29) (74) (1722) (813) (368) (35) IOMM WGZ-1 WGZ 030A through 100A 23

24 Figure 16, Dimensions WGZ 0AA 080AA Door Swing Clearance W Evaporator Recommended for Servicing "G" Disch Conn "E" Liquid Conn H Y Z L A MicroTech II User Interface Control Connection "G" Disch. System #2 "G" Disch. System #1 Inlet Evaporator Outlet T "E" Liquid System #2 "E" Liquid System # Power Connections (2) (22mm) (4) (22mm) Mounting Holes X WGZ MODEL NO (3556) Maximum Overall Dimensions in. (mm) Evaporator Water Connections Victaulic in. (mm) L W H Size A (813) (1676) (76) (2978) (813) (1676) (76) (3018) (813) (1676) (76) (3112) (3620) (3620) Refrigerant Connections (OD) in. (mm) Liquid E (29) (29) (29) Center of Gravity in. (mm) Discharge G T X Y Z (35) (35) (41) (41) 11 (280) 12 (306) 12 (306) 64.3 (1633) 63 (10) 64.3 (1633) 33.8 (859) 36.6 (930) 38 (965) 14.2 (362) 14.1 (359) 14.1 (359) 24 WGZ 030A through 100A IOMM WGZ-1

25 Figure 17, Dimensions WGZ 090AA 100AA Door Swing Clearance W Evaporator Recommended for Servicing "G" Discharge Conn H Y "E" Liquid Conn Z L A MicroTech II User Interface Control Connection Inlet Evaporator Outlet T "G" Discharge Conn System "G" Discharge Conn System "E" Liquid Conn System 2 "E" Liquid Conn System Power Connections (2).875" (22 mm) (4).875" (22 mm) Diameter Mounting Holes X WGZ MODEL NO (3667) Maximum Overall Dimensions in. (mm) Evaporator Water Connections (Victaulic) in. (mm) L W H Size A (813) (1676) (76) (3216) (813) (1676) (76) (3274) (3667) Refrigerant Connections (OD) Liquid E (29) (29) Center of Gravity in. (mm) Discharge G T X Y Z (41) (41) 15.8 (401) 15.8 (401) 63.1 (13) 67.5 (1715) 38.4 (975) 38.6 (980) 14.1 (359) 13.6 (346) IOMM WGZ-1 WGZ 030A through 100A 25

26 Physical Data AW Water-Cooled Table 8, WGZ-030AW - WGZ-055AW WGZ UNIT SIZE Unit ARI conditions tons, (kw) (1) 31.6 (111.1) 34.9 (122.7) 40.1 (141) 44.2 (155) 48.6 (171) 54.3 (191) No. Circuits COMPRESSORS Nominal Horsepower Number (2) Unloading Steps 27 / 50 / / 50 / / 50 / / 50 / / 50 / / 50 / 77 Oil Charge per Compressor oz., (l) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) CONDENSER Number No. Refrigerant Circuits Diameter, in., (mm) 10 (254) 10 (254) 10 (254) 10 (254) 10 (254) 10 (254) Tube Length, in., (mm) 120 (3048) 120 (3048) 120 (3048) 120 (3048) 120 (3048) 120 (3048) Design W.P. psig, (kpa): Refrigerant Side 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) Water Side 232 (1599) 232 (1599) 232 (1599) 232 (1599) 232 (1599) 232 (1599) No. of Passes Pump-Out Capacity, lb., (kg) (3) 279 (126.6) 273 (123.8) 2 (117.9) 253 (114.8) 240 (108.9) 234 (106.1) Connections: Water In & Out, in, (mm) victaulic 4 (102) 4 (102) 4 (102) 4 (102) 4 (102) 4 (102) Relief Valve, Flare In., (mm) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Purge Valve, Flare In., (mm) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Vent & Drain, in. (mm) FPT ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Liquid Subcooling Integral Integral Integral Integral Integral Integral EVAPORATOR Number No. Refrigerant Circuits Water Volume, gallons, (l) 3.9 (14.7) 4.3 (16.4) 5 (18.9) 5.7 (21.4) 6.3 (23.9) 7.2 (27.3) Refrig. Side D.W.P., psig, (kpa) 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) Water Side D.W.P., psig, (kpa) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) Water Connections: Inlet & Outlet, in., (mm) victaulic 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) Drain & Vent (NPT INT.) Field Field Field Field Field Field UNIT DIMENSIONS Length In., (mm) (3406) (3406) (3406) (3406) (3406) (3406) Width In., (mm) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) Height In., (mm) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) UNIT WEIGHTS Operating Weight, lb., (kg) 2692 (1219) 27 (1250) 2866 (1298) 2966 (1344) 3058 (1385) 3213 (1455) Shipping Weight, lb., (kg) 2551 (1157) 26 (1182) 2684 (1217) 2763 (1253) 2828 (1283) 2973 (1349) Operating Charge, lb., (kg) R (45.4) 99 (44.9) 94 (42.6) 92 (41.7) 88 (39.9) 89 (40.4) Notes: 1. Certified in accordance with ARI Standard 550/ All units have two compressors per circuit in parallel % full R-22 at 90 F (32 C) per unit. 26 WGZ 030A through 100A IOMM WGZ-1

27 Table 9, WGZ-0AW - WGZ-100AW WGZ UNIT SIZE Unit ARI conditions tons, (kw) (1).3 (212) 68.0 (239) 75.6 (266) 84.4 (297) 93.7 (330) No. Circuits COMPRESSORS Nominal Horsepower Number (2) Unloading Steps 25 / 50 / / 50 / / 50 / / 50 / / 50 / 75 Oil Charge, per compressor oz. (l) 140 (4.1) 140 (4.1) 148 (4.3) 148 (4.3) 200 (5.9) 200 ( (5.9 CONDENSER Number No. Refrigerant Circuits Diameter, in. (mm) 14 (356) 14 (356) 14 (356) 14 (356) 14 (356) Tube Length, in. (mm) 120 (3048) 120 (3048) 120 (3048) 120 (3048) 120 (3048) Design W.P., psig (kpa): Refrigerant Side 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) Water Side 232 (1599) 232 (1599) 232 (1599) 232 (1599) 232 (1599) No. of Passes Pump-Out Capacity lb., (kg) (3) 481 (218.2) 462 (209.6) 449 (203.7) 429 (194.6) 409 (185.5) Connections: Water In & Out, in., (mm) (4) 5 (127) 5 (127) 5 (127) 5 (127) 5 (127) Relief Valve, Flare in., (mm) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Purge Valve, Flare in. (mm) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Vent & Drain, in. (mm) FPT ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) ½ (12.7) Liquid Subcooling Integral Integral Integral Integral Integral EVAPORATOR Number No. Refrigerant Circuits Water Volume, gallons (l) 8.1 (30.7) 9.2 (34.9) 10.8 (40.7) 12.8 (48.3) 13.9 (52.5) Refrigerant Side D.W.P., psig, 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) (kpa) Water Side D.W.P., psig, (kpa) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) Water Connections: In & Out, in. (mm) victaulic 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) Drain & Vent Field Field Field Field Field UNIT DIMENSIONS Length, in. (mm) (3663) (3726) (3726) 149 (3784) 149 (3784) Width, in. (mm) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) Height, in. (mm) 66 (1676) 66 (1676) 66 (1676) 66 (1676) 66 (1676) UNIT WEIGHTS Operating Weight, lb. (kg) 3809 (1725) 4025 (1823) 4289 (1943) 4484 (2031) 4627 (2096) Shipping Weight, lb. (kg) 3500 (1588) 3716 (1686) 3947 (1790) 4094 (1857) 4197 (1904) R-22 Ref. Charge, lb. (kg) 173 (78.5) 167 (75.7) 163 (73.9) 151 (68.5) 151 (68.5) Notes: 1. Certified in accordance with ARI Standard 550/ All units have two compressors per circuit in parallel % full R-22 at 90 F (32 C) per unit. 4. Victaulic connections. IOMM WGZ-1 WGZ 030A through 100A 27

28 AA Remote Condenser Table 10, WGZ-030AA - WGZ-055AA WGZ UNIT SIZE F LWT, 125 F SDT tons, (kw) 29 (103) 31.6 (112) 36.6 (130) 40.7 (144) 44.7 (158) 49.8 (177) No. Circuits COMPRESSORS Nominal Horsepower Number (2) Unloading Steps 27 / 50 / / 50 / / 50 / / 50 / / 50 / / 50 / 77 Oil Charge, per compressor oz. (l) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) 140 (4.1) Discharge Valve In., (mm) (28) (28) (28) (28) (28) (28) (35) EVAPORATOR No. Refrigerant Circuits Water Volume, gallons, (l) 3.9 (14.7) 4.3 (16.4) 5 (18.9) 5.7 (21.4) 6.3 (23.9) 7.2 (27.3) Refrig. Side D.W.P. psig (kpa) 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) Water Side D.W.P. psig (kpa) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) Water Connections: Inlet & Outlet, in., (mm) (1) 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) Drain & Vent Field Field Field Field Field Field UNIT DIMENSIONS Length In., (mm) (3109) (3109) (3109) (3109) (3109) (3134) Width In., (mm) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) Height In., (mm) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) 63.5 (1613) UNIT WEIGHTS Operating Weight, lb. (kg) 2162 (981) 2204 (1000) 2257 (1024) 2329 (1056) 2370 (1075) 2505 (1136) Shipping Weight, lb. (kg) 2134 (968) 2172 (985) 2219 (1007) 2281 (1035) 2315 (1050) 2452 (1112) Holding Charge, lb. (kg) R (2.7) 6.1 (2.8) 6.4 (2.9) 6.6 (3) 7.0 (3.2) 9.7 (4.4) Table 11, WGZ-0AA - WGZ-100AA WHR UNIT SIZE F LWT, 125 F SDT tons, (kw) 54.9 (195) 62.1 (220) 69.5 (246) 77.9 (276) 85.9 (305) No. Circuits COMPRESSORS Nominal Horsepower Number (3) Unloading Steps 25 / 50 / / 50 / / 50 / / 50 / / 50 / 75 Oil Charge oz 140 (4.1) 140 (4.1) 148 (4.3) 148 (4.3) 148 (4.3) 148 (4.3) 200 (5.9) 200 (5.9) 200 (5.9) EVAPORATOR No. Refrigerant Circuits Water Volume, gallons (l) 8.1 ( (34.9) 10.8 (40.7) 12.8 (48.3) 13.9 (52.5) Refrigerant Side D.W.P., psig 450 (3102) 450 (3102) 450 (3102) 450 (3102) 450 (3102) (kpa) Water Side D.W.P., psig (kpa) 363 (2503) 363 (2503) 363 (2503) 363 (2503) 363 (2503) Water Connections: Inlet & Outlet, in. (mm) (1) 3 (76) 3 (76) 3 (76) 3 (76) 3 (76) Drain & Vent Field Field Field Field Field UNIT DIMENSIONS Length, in. (mm) 140 (3556) (3620) (3620) (3677) (3677) Width, in. (mm) 32 (813) 32 (813) 32 (813) 32 (813) 32 (813) Height, in. (mm) 66 (1676) 66 (1676) 66 (1676) 66 (1676) 66 (1676) UNIT WEIGHTS Operating Weight, lb. (kg) 2771 (1257) 2942 (1334) 3154 (1431) 3271 (1484) 3346 (1518) Shipping Weight, lb. (kg) 2701 (1225) 2871 (1302) 3071 (1393) 3172 (1439) 3238 (1469) Holding Charge, lb. (kg) R (4.5) 10.5 (4.7) 11.1 (5) 11.8 (5.4) 12.3 (5.6) Notes: 1. Victaulic connections. 2. All units have two compressors per circuit in parallel. 28 WGZ 030A through 100A IOMM WGZ-1

29 Operating Limits Maximum allowable condenser water pressure is 232 psig (1599 kpa). Maximum allowable cooler water pressure is 363 psig (2509 kpa). Maximum design saturated discharge temperature is 140 F ( C). Maximum allowable water temperature to cooler in a non-operating cycle is 100 F (37.8 C). Maximum entering water temperature for operating cycle is 90 F (32.2 C) (during system changeover from heating to cooling cycle). Minimum leaving water temperature from the cooler without freeze protection is 40 F (4.4 C). Minimum entering tower condenser water temperature is F (15.6 C). Components Figure 18, Compressor Locations Evaporator Evaporator and Condenser Connections Circuit 2 Circuit 1 Control Panel Table 12, Major Components Unit System #1 System #2 Evap. Cond. Expansion Valve Size Vessel Vessel Comp. #1 Comp. #3 Comp. #2 Comp. #4 Size Size System #1 System #2 030 ZR90K3 ZR90K3 ZR11M3 ZR11M3 AC250-70DQ C OVE-20-CP100 OVE-20-CP ZR11M3 ZR11M3 ZR11M3 ZR11M3 AC250-78DQ C OVE-20-CP100 OVE-20-CP ZR12M3 ZR12M3 ZR12M3 ZR12M3 AC250-90DQ C OVE-20-CP100 OVE-20-CP ZR12M3 ZR12M3 ZR16M3 ZR16M3 AC DQ C OVE-30-CP100 OVE-30-CP ZR16M3 ZR16M3 ZR16M3 ZR16M3 AC DQ C OVE-30-CP100 OVE-30-CP ZR16M3 ZR16M3 ZR19M3 ZR19M3 AC DQ C OVE-30-CP100 Y929-VCP100 0 ZR19M3 ZR19M3 ZR19M3 ZR19M3 AC DQ C Y929-VCP100 Y929-VCP ZR19M3 ZR19M3 ZR250KC ZR250KC AC DQ C Y929-VCP100 Y929-VCP ZR250KC ZR250KC ZR250KC ZR250KC AC DQ C Y929-VCP100 Y929-VCP ZR250KC ZR250KC ZR300KC ZR300KC AC DQ C OVE-55-CP100 OVE-55-CP ZR300KC ZR300KC ZR300KC ZR300KC AC DQ C OVE-55-CP100 OVE-55-CP100 IOMM WGZ-1 WGZ 030A through 100A 29

30 Wiring Field Wiring, Power The WGZ A vintage chillers are built standard with compressor contractors and power terminal block, designed for single power supply to the unit. Optional power connections include a non-fused disconnect switch mounted in the control box or multi-point power connection. A factory installed control circuit transformer is standard. Optionally, a field-installed control power source can be wired to the unit. Circuit breakers for backup compressor short circuit protection are standard on all units. Wiring and conduit selections must comply with the National Electrical Code and/or local requirements. An open fuse indicates a short, ground, or overload. Before replacing a fuse or restarting a compressor, the trouble must be found and corrected. Tables in the Electrical Data section (page 32) give specific information on recommended wire sizes. Unit power inlet wiring must enter the control box (right side) through a patch plate provided for field terminating conduit. (Refer to control panel dimension drawings for general location of power inlet and components.) NOTE: Use only copper conductors in main terminal block. Terminations are sized for copper only. Field Wiring, Control A factory-mounted control transformer is provided to supply the correct control circuit voltage. The transformer power leads are connected to the power block PB1 or disconnect switch DS1. Interlock Wiring, Condenser Pump Starter or Air Cooled Condenser Fan Starter Provisions are made for interlocking a condenser pump starter, tower fans, a tower bypass valve, or up to eight air-cooled condenser fan contactors to be controlled by the MicroTech II unit controller. Condenser fan operation can also be controlled by pressure switches supplied with the condenser. Coil voltage must be 115 volts with a maximum of 20 VA. An evaporator and condenser (water-cooled units only) flow switch is necessary on all units. It is also advisable to wire a chilled water pump interlock in series with the flow switch for additional freeze protection. Ambient Air Sensor Units with a remote air-cooled condenser will have an outdoor air sensor furnished with the unit, inside the control panel and wired to the correct terminals. It must be installed outdoors in a location that will give the true outdoor temperature that the condenser coils will see. Splicing of the sensor lead may be required. The sensor must be installed for the unit to operate. 30 WGZ 030A through 100A IOMM WGZ-1

31 Unit Configuration The chiller unit has two refrigerant circuits, two tandem scroll compressors (total of four), a single two-circuited brazed plate evaporator, a single two-circuited water-cooled condenser, interconnecting refrigerant piping and a control panel with associated sensors and transducers. Figure 19, Schematic Piping Diagram (One of Two Circuits) T P S Chilled Water LWT Evaporator P 1 Comp #1 Comp #2 CV Condenser Condenser Water T S S F-D S Legend: T Temperature Sensor Relief Valve TP Pressure Transducer TS Schrader Fitting P 1 Pressure (High Pressure Cutout) Thermal Expansion Valve LWT S Temperataure Sensor, Leaving Chilled Water Control Solenoid Valve CV Sight Glass / Moisture Indicator Charging Valve Angle Valve F-D Filter-Drier Ball Valve IOMM WGZ-1 WGZ 030A through 100A 31

32 Electrical Data Table 13, Compressor Amp Draw, WGZ WGZ 100 WGZ Unit Size Rated Load Amps (1) Locked Rotor Amps (2) Voltage 3-Phase Freq (Hz) Per compressor (2 / circuit) Across-The-Line Start Circuit 1 Circuit 2 Circuit 1 Circuit NOTE: 1. Compressor RLA values are for wire sizing purposes only and do not reflect normal operating current draw. 32 WGZ 030A through 100A IOMM WGZ-1

33 Table 14, Wire Sizing Amps, WGZ WGZ 100 WGZ Unit Size Voltage 3-Phase Freq. (Hz) Minimum Circuit Ampacity (MCA) (1) Single Point Power Multiple Point Power Supply(3) Supply(2) Circuit 1 Circuit NOTES: 1. Unit wire sizing amps are equal to 125% of the largest compressor-motor RLA, plus 100% of RLA of all other loads in the circuit including control transformer. 2. Single point power supply requires a single fused disconnect to supply electrical power to the unit. 3. Multiple point power supply requires two independent power circuits with separate fused disconnects. (Two compressor circuits and control circuit will be wired to Circuit #1 from the factory). IOMM WGZ-1 WGZ 030A through 100A 33

34 Table 15, Fuse Sizing, WGZ WGZ 100 WGZ Unit Size Recommended Fuse Size(1) Maximum Fuse Size(2) Voltage Freq. 3-Phase (Hz) Single Point Multiple Point Single Point Multiple Point Total Unit Circuit #1 Circuit #2 Total Unit Circuit #1 Circuit # NOTES: 1. "Recommended Fuse Size" is selected at approximately 150% of the largest compressor RLA, plus 100% of all other circuit load. 2. "Maximum Fuse Size" is selected at approximately 225% of the largest compressor RLA, plus 100% of all other loads. 34 WGZ 030A through 100A IOMM WGZ-1

35 Table 16, Wire Sizing, WGZ WGZ 100 WGZ Unit Size Single Point Multiple Point Voltage Freq. 3-Phase (Hz) Unit Circuit #1 Circuit #2 Number Wire Size Number Wire Size Number Wire Size GA 3 6 GA 3 4 GA GA 3 6 GA 3 4 GA GA 3 10 GA 3 8 GA 3 8 GA 3 10 GA 3 8 GA /0 3 4 GA 3 4 GA /0 3 4 GA 3 4 GA GA 3 8 GA 3 8 GA 3 6 GA 3 8 GA 3 8 GA /0 3 3 GA 3 3 GA /0 3 3 GA 3 3 GA GA 3 8 GA 3 8 GA 3 6 GA 3 10 GA 3 8 GA /0 3 3 GA 3 3 GA /0 3 3 GA 3 3 GA GA 3 8 GA 3 6 GA 3 4 GA 3 8 GA 3 8 GA /0 3 3 GA 3 3 GA /0 3 3 GA 3 3 GA GA 3 6 GA 3 6 GA 3 4 GA 3 8 GA 3 8 GA /0 3 3 GA 3 1 GA /0 3 3 GA 3 1 GA GA 3 6 GA 3 6 GA 3 4 GA 3 8 GA 3 8 GA /0 3 1 GA 3 1 GA /0 3 1 GA 3 1 GA GA 3 6 GA 3 6 GA 3 3 GA 3 8 GA 3 8 GA kcmil 3 1 GA 3 2/ kcmil 3 1 GA 3 2/ GA 3 6 GA 3 4 GA 3 2 GA 3 8 GA 3 6 GA kcmil 3 2/0 3 2/ kcmil 3 2/0 3 2/ /0 3 4 GA 3 4 GA 3 1 GA 3 6 GA 3 6 GA kcmil 3 2/0 3 3/ kcmil 3 2/0 3 3/ /0 3 4 GA 3 3 GA 3 1 GA 3 6 GA 3 4 GA kcmil 3 3/0 3 3/ kcmil 3 3/0 3 3/ /0 3 3 GA 3 3 GA 3 1 GA 3 4 GA 3 4 GA IOMM WGZ-1 WGZ 030A through 100A 35

36 Table 17, Single Point Connection Sizing, WGZ WGZ 100 WGZ Unit Size Single Point Voltage Freq. 3-Phase (Hz) Power Block Disconnect Switch Size (1) Connection (3) Size (2) Connection (3) GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 0 kcmil GA 2/ GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 0 (2) 2GA 0 kcmil GA 400 kcmil 0 (2) 2GA 0 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 500 kcmil 0 (2) 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil NOTES: 1. "Size" is the maximum amperage rating for the terminals or the main electrical device. 2. "Size" is the disconnect part number and not the amperage rating for the terminals or the main electrical device. 3. "Connection" is the range of wire sizes that the terminals on the electrical device will accept. 36 WGZ 030A through 100A IOMM WGZ-1

37 Table 18, Multiple Point Connection Sizing, WGZ WGZ 100 WGZ Unit Size Multiple Point Circuit #1 Multiple Point Circuit #2 Voltage Freq. 3-Phase (Hz) Power Block Disconnect Switch Power Block Disconnect Switch Size (1) Connection (3) Size (2) Connection (3) Size (1) Connection (3) Size (2) Connection (3) GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 8 GA GA 2/ GA 8 GA GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/0 1 8 GA 2/ GA 2/ GA 300 kcmil GA 2/0 1 8 GA 2/ GA 2/ GA 300 kcmil GA 2/ GA 4 GA GA 2/ GA 4 GA GA 2/ GA 1 GA GA 2/ GA 1 GA GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 2/ GA 2/ GA 2/ GA 2/ GA 1 GA GA 2/ GA 1 GA GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 2/ GA 2/ GA 2/ GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 2/ GA 2/ GA 2/ GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 2/ GA 300 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 2/ GA 300 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 2/ GA 2/ GA 2/ GA 300 kcmil GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/ GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 400 2GA 0 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 400 kcmil 200 6GA 300 kcmil GA 2/ GA 300 kcmil GA 2/ GA 300 kcmil GA 2/0 1 8 GA 2/ GA 2/0 1 8 GA 2/0 NOTES: 1. "Size" is the maximum amperage rating for the terminals or the main electrical device. 2. "Size" is the disconnect part number and not the amperage rating for the terminals or the main electrical device. 3. "Connection" is the range of wire sizes that the terminals on the electrical device will accept. IOMM WGZ-1 WGZ 030A through 100A 37

38 Notes for Electrical Data Single Point Power: 1. Wire sizing amps is 10 amps if a separate 115V power supply is used. 2. Recommended power lead wire sizes for 3 conductors per conduit are based on 100% conductor ampacity in accordance with NEC. Voltage drop has not been included. Therefore, it is recommended that power leads be kept short. All terminal block connections must be made with copper (type THW) wire. 3. The recommended power lead wire sizes are based on an ambient temperature of 86 F (30 C). Ampacity correction factors must be applied for other ambient temperatures. Refer to the National Electrical Code Handbook. 4. Must be electrically grounded according to national and local electrical codes. Power Limitations: 1. Voltage within ± 10 percent of nameplate rating. 2. Phase unbalance not to exceed 3%. Notes for Field Wiring Data 1. Requires a single disconnect to supply electrical power to the unit. This power supply must either be fused or use an HACR type circuit breaker. 2. All field wiring to unit power block or optional non-fused disconnect switch must be copper. 3. All field wire size values given in table apply to 75 C rated wire per NEC. 38 WGZ 030A through 100A IOMM WGZ-1

39 Field Wiring Diagrams Figure 20, WGZ 030AW 100AW Field Wiring Diagram DISCONNECT (BY OTHERS) 3 PHASE POWER SUPPLY UNIT MAIN TERMINAL BLOCK FUSED CONTROL CIRCUIT TRANSFORMER GND LUG TO COMPRESSOR(S) FIELD SUPPLIED OPTION 120VAC CONTROL POWER DISCONNECT (BY OTHERS) N FACTORY SUPPLIED ALARM FIELD WIRED ALARM BELL OPTION REMOTE STOP SWITCH (BY OTHERS) ICE MODE SWITCH (BY OTHERS) ALARM BELL RELAY 10A FUSE (BY OTHERS) CDW PUMP RELAY (BY OTHERS) 120 VAC 1.0 AMP MAX TOWER FAN #1 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX TIME OFF CLOCKAUTO ON CHW PUMP RELAY (BY OTHERS) 120 VAC 1.0 AMP MAX 120 VAC TOWER FAN #2 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX MANUAL AUTO OFF ON MANUAL TB CONTROLLER J15-N08 TB1-12 J16-N09 TB1-12 J16-N TB GND TB1-20 CONTROL CIRCUIT FUSE N N N 120VAC 120 VAC 120 VAC 120 VAC 120 VAC IF REMOTE STOP CONTROL 897 IS USED, REMOVE LEAD 897 FROM TERM 40 TO IF ICE MODE IS USED REMOVE LEAD FROM TERM 42 TO 55. CHW FLOW SWITCH --MANDATORY-- (BY OTHERS) CDW FLOW SWITCH --MANDATORY-- (BY OTHERS) 4-20 MA FOR CHW RESET (BY OTHERS) 4-20 MA FOR DEMAND LIMIT (BY OTHERS) NOR. OPEN PUMP AUX. CONTACTS (OPTIONAL) NOR. OPEN PUMP AUX. CONTACTS (OPTIONAL) GND GND CONTROLLER J11 Rx-/Tx- Rx+/Tx+ GND * COMMUNICATION PORT R4 IOMM WGZ-1 WGZ 030A through 100A 39

40 Figure 21, WGZ 030AA 100AA Field Wiring Diagram (Remote Condenser) UNIT MAIN DISCONNECT (BY OTHERS) TERMINAL BLOCK 3 PHASE POWER SUPPLY FUSED CONTROL CIRCUIT TRANSFORMER GND LUG TO COMPRESSOR(S) FIELD SUPPLIED OPTION N 120VAC CONTROL POWER DISCONNECT (BY OTHERS) FACTORY SUPPLIED ALARM FIELD WIRED ALARM BELL OPTION 10A FUSE (BY OTHERS) ALARM BELL RELAY 120 VAC CHW PUMP RELAY (BY OTHERS) 120 VAC 1.0 AMP MAX TB TB1-20 CONTROL CIRCUIT FUSE N 120VAC 120 VAC 15 TIME OFF CLOCK AUTO TB2 GND REMOTE STOP SWITCH ON (BY OTHERS) IF REMOTE STOP CONTROL MANUAL IS USED, REMOVE LEAD AUTO OFF FROM TERM 40 TO 53. ICE MODE SWITCH ON IF ICE MODE IS USED (BY OTHERS) REMOVE LEAD MANUAL 55 FROM TERM 42 TO 55. CHW FLOW SWITCH --MANDATORY-- (BY OTHERS) CONTROLLER J11 NOR. OPEN PUMP AUX. 33 CONTACTS (OPTIONAL) Rx-/Tx * 2 COMMUNICATION Rx+/Tx+ PORT 4-20 MA FOR CHW RESET 38 GND 3 (BY OTHERS) MA FOR DEMAND LIMIT 38 GND (BY OTHERS) TB3 GND 24 VAC 62 N 65 LIQUID LINE #1 SOLENOID 24 VAC AMP MAX 24 VAC 63 N LIQUID LINE #2 SOLENOID VAC AMP MAX 24 VAC 67 N HOT GAS BYPASS #1 SOLENOID 70 OPTIONAL 24 VAC AMP MAX VAC N HOT GAS BYPASS #2 SOLENOID VAC AMP MAX CONTROLLER 120 VAC J15-N08 N FAN MOTOR #1 COIL (BY OTHERS) TB VAC 1.0 AMP MAX 120 VAC J16-N09 NOTE: CONDENSER FAN MOTORS CAN ALSO BE CONTROLLED BY PRESSURE SWITCHES ON THE CONDENSER. FAN MOTOR #2 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX FAN MOTOR #3 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX FAN MOTOR #4 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX FAN MOTOR #5 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX FAN MOTOR #6 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX J16-N010 J16-N011 J18-N013 J22-N016 J22-N VAC 120 VAC 120 VAC 120 VAC 120 VAC R4 FAN MOTOR #7 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX FAN MOTOR #8 COIL (BY OTHERS) 120 VAC 1.0 AMP MAX J22-N VAC 40 WGZ 030A through 100A IOMM WGZ-1

41 Control Panel Layout Figure 22, Typical Control Panel MicroTech II Unit Controller (3) 24V Controller Transformers Terminal Strips 110V Control Transformer (CT) S1, PS1, PS2 Switches (4) Compressor Contactors Space for Optional Circuit Breakers and Multi-point Connection Disconnect Switch Grounding Lug NOTES: 1. Additional space provided in the upper right section for extra components required for optional multiple point power connection and optional circuit breakers. 2. Front door has opening on top for access to the MicroTech II controller for viewing display and making keypad entries without opening the panel door. Motor Protection Module The motor protection system consists of an external control module, located on each compressor, connected to a series of thermistors located in the motor windings and the compressor discharge port. If the windings experience an over-temperature condition or the discharge temperature is excessive, the module will trip and shut off the compressor for a 30-minute time delay. IOMM WGZ-1 WGZ 030A through 100A 41