Tranquility Modular Water-to-Water (TMW) Series

Transcription

1 Tranquility Modular Water-to-Water (TMW) Series Table of Contents Commercial EarthPure Water-Source Heat Pumps 60Hz Model Nomenclature 3 General Information 4 Unit Physical Data 6 TMW Unit Dimensional Data 7 TMW170 & Unit Dimensional Data 8 Unit Installation 9 Piping Installation 10 Water-Loop Heat Pump Applications 11 Ground-Water Heat Pump Applications 12 Ground-Loop Heat Pump Applications 14 Electrical - Line Voltage 16 Electrical - Accessories 17 Electrical - Line Voltage 18 Electrical - Low Voltage 19 TMW Series Wiring Diagram Matrix 20 Typical Wiring Diagrams 21 CXM Controls 32 DXM Controls 35 Safety Features - CXM/DXM Controls 36 Piping System Cleaning & Flushing 37 Unit & System Checkout 38 Unit Start Up Procedure 39 Operating Pressures 40 Preventative Maintenance 42 Warranty (International) 43 Warranty (US & Canada) 44 Start-Up Log Sheet 45 Refrigeration Troubleshooting Form 46 Revision History 48 Installation, Operation & Maintenance 97B0059N03 Revised: July 14, 2017

2 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 This Page Intentionally Left Blank 2 ClimateMaster Water-Source Heat Pumps

3 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Model Nomenclature MODEL TYPE TM = TRANQUILITY MEDIUM TEMPERATURE TM W A G C 1 0 C 0 C S S = STANDARD CONFIGURATION W = WATER TO WATER HEAT PUMP UNIT SIZE E,F,G,H,U,V F,G,H,N,U F,G,H,N,U F,H,N,U F,H,N,U REVISION LEVEL A = CURRENT C = CXM D = DXM L = CXM w/lon M = DXM w/lon N = CXM w/mpc P = DXM w/mpc F = CXM G = DXM H = CXM w/lon J = DXM w/lon T = CXM w/mpc U = DXM w/mpc VOLTAGE G = /60/1 - R410A E = 265/60/1 - R410A V = /50/1 - R410A H = /60/3 - R410A F = 460/60/3 - R410A U = /50/3 - R410A N = 575/60/3 - R410A ETL CONTROLS APPROVED FOR USA & CANADA CE APPROVED FOR EUROPE HOT WATER GENERATOR OPTIONS (TMW ONLY) CABINET INSULATION SOURCE WATER COIL OPTIONS C = Copper N = Cupro-Nickel 0 = NONE 2 = HWG (COIL ONLY) COMMERCIAL 1 = COMMERCIAL EXTENDED RANGE 2 = COMMERCIAL EXTENDED RANGE w/ultra QUIET LOAD WATER COIL OPTIONS C = COPPER N = CUPRO-NICKEL RESERVED-FOR FUTURE OPTIONS 0 = NONE NOTES: 1. FRONT ACCESS PANELS ARE STAINLESS STEEL, REST OF THE UNIT IS PAINTED BLACK (PEWTER) 2. LOAD/SOURCE WATER CONNECTIONS ARE TOP FOR 170 AND 340. WATER CONNECTIONS ARE FRONT FOR 036, 060 & 120. climatemaster.com 3

4 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 General Information Safety Warnings, cautions, and notices appear throughout this manual. Read these items carefully before attempting any installation, service, or troubleshooting of the equipment. DANGER: Indicates an immediate hazardous situation, which if not avoided will result in death or serious injury. DANGER labels on unit access panels must be observed. WARNING: Indicates a potentially hazardous situation, which if not avoided could result in death or serious injury. CAUTION: Indicates a potentially hazardous situation or an unsafe practice, which if not avoided could result in minor or moderate injury or product or property damage. NOTICE: Notification of installation, operation, or maintenance information, which is important, but which is not hazard-related. WARNING! WARNING! To avoid the release of refrigerant into the atmosphere, the refrigerant circuit of this unit must be serviced only by technicians who meet local, state, and federal profi ciency requirements. WARNING! WARNING! All refrigerant discharged from this unit must be recovered WITHOUT EXCEPTION. Technicians must follow industry accepted guidelines and all local, state, and federal statutes for the recovery and disposal of refrigerants. If a compressor is removed from this unit, refrigerant circuit oil will remain in the compressor. To avoid leakage of compressor oil, refrigerant lines of the compressor must be sealed after it is removed. WARNING! WARNING! The installation of water-source heat pumps and all associated components, parts, and accessories which make up the installation shall be in accordance with the regulations of ALL authorities having jurisdiction and MUST conform to all applicable codes. It is the responsibility of the installing contractor to determine and comply with ALL applicable codes and regulations. CAUTION! CAUTION! To avoid equipment damage, DO NOT use these units as a source of heating or cooling during the construction process. The mechanical components and fi lters will quickly become clogged with construction dirt and debris, which may cause system damage. 4 ClimateMaster Water-Source Heat Pumps

5 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Inspection - Upon receipt of the equipment, carefully check the shipment against the bill of lading. Make sure all units have been received. Inspect the carton or crating of each unit, and inspect each unit for damage. Assure the carrier makes proper notation of any shortages or damage on all copies of the freight bill and completes a common carrier inspection report. Concealed damage not discovered during unloading must be reported to the carrier within 15 days of receipt of shipment. If not filed within 15 days, the freight company can deny the claim without recourse. Note: It is the responsibility of the purchaser to file all necessary claims with the carrier. Notify the ClimateMaster Traffic Department of all damage within fifteen (15) days of shipment. Storage - Equipment should be stored in its original packaging in a clean, dry area. Store units in an upright position at all times. Do not stack TMW170 or 340. The stack limit for TMW036, 060 and 120 is three. Unit Protection - Cover units on the job site with either shipping packaging, vinyl film, or an equivalent protective covering. Cap the open ends of pipes stored on the job site. In areas where painting, plastering, and/or spraying has not been completed, all due precautions must be taken to avoid physical damage to the units and contamination by foreign material. Physical damage and contamination may prevent proper start-up and may result in costly equipment clean-up. Examine all pipes, fittings, and valves before installing any of the system components. Remove any dirt or trash found in or on these components. CAUTION! CAUTION! All three phase scroll compressors must have direction of rotation verifi ed at start-up. Verifi cation is achieved by checking compressor Amp draw. Amp draw will be substantially lower compared to nameplate values. Additionally, reverse rotation results in an elevated sound level compared to correct rotation. Reverse rotation will result in compressor internal overload trip within several minutes. Verify compressor type before proceeding. CAUTION! CAUTION! DO NOT store or install units in corrosive environments or in locations subject to temperature or humidity extremes (e.g., attics, garages, rooftops, etc.). Corrosive conditions and high temperature or humidity can signifi cantly reduce performance, reliability, and service life. Always move and store units in an upright position. Tilting units on their sides may cause equipment damage. CAUTION! CAUTION! CUT HAZARD - Failure to follow this caution may result in personal injury. Sheet metal parts may have sharp edges or burrs. Use care and wear appropriate protective clothing, safety glasses and gloves when handling parts and servicing heat pumps. NOTICE! Failure to remove shipping brackets from spring-mounted compressors will cause excessive noise, and could cause component failure due to added vibration. Pre-Installation - Installation, Operation, and Maintenance instructions are provided with each unit.. The installation site chosen should include adequate service clearance around the unit. Before unit startup, read all manuals and become familiar with the unit and its operation. Thoroughly check the system before operation. Prepare units for installation as follows: 1. Compare the electrical data on the unit nameplate Twith ordering and shipping information to verify that the correct unit has been shipped. 2. Keep the cabinet covered with the shipping packaging until installation is complete and all plastering, painting, etc. is finished. 3. Verify refrigerant tubing is free of kinks or dents and that it does not touch other unit components. 4. Inspect all electrical connections. Connections must be clean and tight at the terminals. climatemaster.com 5

6 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Unit Physical Data Model Compressor (qty) Scroll (1) Scroll (2) Scroll (1) Scroll (2) Factory Charge HFC-410A (lbs) [kg] per circuit 4.5 [2.04] 5.5 [2.49] 14.9 [6.8] Water Connection Size Source/Load (in) 3/ /2 2 Hot Water Generator FPT (in) ½ N/A Weight - Operating (lbs) [kg] 348 [158] 360 [163] 726 [329] 725 [329] 1330 [604] Weight - Packaged (lbs) [kg] 373 [169] 385 [175] 770 [349] 765 [347] 1340 [608] Water Volume (Source) Gallons (Liters) 0.96 (3.64) 1.33 (5.04) 2.65 (10.02) 3.50 (13.27) 6.72 (25.44) Dual isolated compressor mounting Balanced port expansion valve (TXV) Insulated Source and Load Water Coils standard Insulated Refrigerant Circuit standard Compressor on (green) and fault (red) light Unit Maximum Water Working Pressure Options Max Working Pressure PSIG [kpa] Base Unit 300 [2,068] Motorized Valves 400 [2,758] 6 ClimateMaster Water-Source Heat Pumps

7 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 TMW Unit Dimensional Data B A 1.8 (4.6 cm) C M 1.0 (2.5 cm) L K (2.5 cm) E F G H J Notes: 1. Front & side access is preferred for service access. However, all components may be serviced from the front access panel if side access is not available. 2. While clear access to all removable panels is not required, installer should take care to comply with all building codes and allow adequate clearance for future field services. 3 Ft Notes 1 & 2 Optional Service Access 3 Ft Notes 1 & 2 Required Service Access D B A 7.2 (18.3 cm) 1.7 (4.3 cm) 2.7 (6.9 cm) C 1.3 (3.3 cm) (7.4 cm) 4.0 (10.1 cm 3 Ft Notes 1 & 2 Optional Service Access 3 Ft Notes 1 & 2 Required Service Access Water to Water Overall Cabinet A Depth B Width C Height Water Connections D Source (Outdoor) Water In E Source (Outdoor) Water Out F Load (Indoor) Water In G Load (Indoor) Water Out H HWG Water In J HWG Water Out Electric Access Plugs K Low Voltage L External Pump in cm in cm M Power Supply climatemaster.com 7

8 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 TMW170 & Unit Dimensional Data Load Source Top Header Access Panel Electrical Access Panel 21.0 [533] 5.4 [138] 12.3 [313] 15.0 [381] 15.0 [381] Top View 4.5 [114] 4.3 [108] 4.3 [108] 4.5 [114] 2 IPT Water Connections Power Supply Wiring x 2.0 [ 34.9 x 50.8] Double KO Control Wiring x [ 28.6 x 34.9] Double KO Side Optional (Single Unit) 3ft. (91cm) Additional Service Access Refrig. Circuit Access Panel Front Compressor Access Panel Minimum 3ft. [91cm] Required Service Access NOTE 2 Fault/Run Lights 64.5 [1638] Left Side View Front View 45.1 [1146] 26.3 [669] Notes: 1. Dimensions shown in inches and [millimeters]. 2. For multiple units placed side by side, allow sufficient space front or back to remove unit. 8 ClimateMaster Water-Source Heat Pumps

9 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Unit Installation TMW Unit Location - These units are not designed for outdoor installation. Locate the unit in an INDOOR area that allows enough space for service personnel to perform typical maintenance or repairs. The installation of water source heat pump units and all associated components, parts and accessories which make up the installation shall be in accordance with the regulations of ALL authorities having jurisdiction and MUST conform to all applicable codes. It is the responsibility of the Installing Contractor to determine and comply with ALL applicable codes and regulations. Locate the unit in an indoor area that allows easy removal of access panels, and has enough space for service personnel to perform maintenance or repair. Provide sufficient room to make water and electrical connections.. Any access panel screws that would be difficult to remove after the unit is installed should be removed prior to setting the unit. These units are not approved for outdoor installation and, therefore, must be installed inside the structure being conditioned. Do not locate in areas where ambient conditions are not maintained within F [4-38 C]. PIPING INSTALLATION Installation of Supply and Return Piping Follow these piping guidelines. 1. Install a drain valve at the base of each supply and return riser to facilitate system flushing. 2. Install shut-off / balancing valves and unions at each unit to permit unit removal for servicing. 3. Place strainers at the inlet of each system circulating pump. 4. Select the proper hose length to allow slack between connection points. Hoses may vary in length by +2% to -4% under pressure. 5. Exceeding the minimum bend radius may cause the hose to collapse which reduces water flow rate. Install an angle adapter to avoid sharp bends in the hose when the radius falls below the required minimum and causes a slight kink. Insulation is not required on loop water piping except where the piping runs through unheated areas or outside the building or when the loop water temperature is below the minimum expected dew point of the pipe ambient temperature. Insulation is required if loop water temperature drops below the dew point. Note: When anti-freeze is used in the loop, assure that it is compatible with Teflon tape or pipe joint compound employed. Maximum allowable torque for brass fittings is 30 ft-lbs [41 N-m]. If a torque wrench is not available, tighten finger-tight plus one quarter turn. Tighten steel fittings as necessary. WARNING! WARNING! Piping must comply with all applicable codes. WARNING! WARNING! Do not bend or kink supply lines or hoses. Pipe joint compound is not necessary when Teflon threaded tape is pre-applied to hose assemblies or when flared-end connections are used. If pipe joint compound is preferred, use compound only in small amounts on the pipe threads of the fitting adapters. Prevent sealant from reaching the flared surfaces of the joint. climatemaster.com 9

10 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Piping Installation WARNING! WARNING! Polyolester Oil, commonly known as POE oil, is a synthetic oil used in many refrigeration systems including those with HFC-410A refrigerant. POE oil, if it ever comes in contact with PVC or CPVC piping, may cause failure of the PVC/CPVC. PVC/CPVC piping should never be used as supply or return water piping with water source heat pump products containing HFC-410A as system failures and property damage may result. CAUTION! CAUTION! Corrosive system water requires corrosion resistant fi ttings and hoses and possibly water treatment. Optional pressure-rated hose assemblies designed specifically for use with ClimateMaster units are available. Similar hoses can be obtained from alternate suppliers. Supply and return hoses are fitted with swivel-joint fittings at one end to prevent kinking during installation. Refer to Figure 1 for an illustration of a Supply/Return Hose Kit. Male adapters secure hose assemblies to the unit and risers. Install hose assemblies properly and check them regularly to avoid system failure and reduced service life. Figure 1: Supply/Return Hose Kit Rib Crimped Swivel Brass Fitting Brass Fitting MPT Length (0.6m Length Standard) MPT LOAD PLUMBING INSTALLATION TMW Unit Load Plumbing - The applications are too varied to describe in this document. However, some basic guidelines will be presented. Much of the discussions on water loop applications would be valid for the load plumbing discussion as well. All plumbing should conform to local codes with the following considerations: Wide temperature variation applications such as heating/cooling coils: - Employ piping materials that are rated for the maximum temperature and pressure combination. This excludes PVC for most heating applications. - Insure that load water flow in high temperature heating applications is at least 3 gpm per ton [3.9 l/m per kw] to improve performance and reduce nuisance high pressure faults. - DO NOT employ plastic to metal threaded joints - Utilize a pressure tank and air separator vent system to equalize pressure and remove air.. Swimming Pool Hot Tub Applications: - Load coax should be isolated with secondary heat exchanger constructed of anti-corrosion material in all chlorine/bromine fluid applications. Note: The manufacturer strongly recommends all piping connections, both internal and external to the unit, be pressure tested by an appropriate method prior to any finishing of the interior space or before access to all connections is limited. Test pressure may not exceed the maximum allowable pressure for the unit and all components within the water system. The manufacturer will not be responsible or liable for damages from water leaks due to inadequate or lack of a pressurized leak test, or damages caused by exceeding the maximum pressure rating during installation. Figure 2: Typical Water Loop Application Load Connections (Hot Water/Chilled Water) Power Disconnect Source Connections (Boiler/Tower, Geothermal Loop) Potable Water Applications: - Potable water systems require field supplied external secondary heat exchanger. - Insure load water flow in high temperature heating applications is at least 3 gpm per ton to improve performance and reduce nuissance to high pressure faults. 10 ClimateMaster Water-Source Heat Pumps

11 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Water-Loop Heat Pump Applications Commercial systems typically include a number of units plumbed to a common piping system. Any unit plumbing maintenance work can introduce air into the piping system, therefore air elimination equipment is a major portion of the mechanical room plumbing. In piping systems expected to utilize water temperatures below 50 F [10 C], 1/2" [13mm] closed cell insulation is required on all piping surfaces to eliminate condensation. Metal to plastic threaded joints should never be employed due to their tendency to leak over time. Teflon tape thread sealant is recommended for FPT water connections (commercial class) to minimize internal fouling of the heat exchanger. Do not overtighten connections and route piping so as not to interfere with service or maintenance access. Hose kits are available from ClimateMaster in different configurations as shown in Figure 2 for connection between the TMW Series and the piping system. The hose kits include shut off valves, P/T plugs for performance measurement, high pressure stainless steel braid hose, "Y" type strainer 20 mesh (841 micron) [0.84mm]) with blowdown valve, and "J" type swivel connection. Balancing valves to facilitate the balancing of the system, and an external low pressure drop solenoid valve for use in variable speed pumping systems, may also be included in the hose kit. The piping system should be flushed to remove dirt, piping chips, and other foreign material prior to operation. See Piping System Cleaning and Flushing Procedures later in this document. The flow rate is usually set between 2.25 gpm and 3 gpm per ton [2.9 l/m and 4.5 l/m per kw] of cooling capacity. ClimateMaster recommends 2.5 gpm Figure 3: Typical Open Loop/Well Application Unit Power Disconnect per ton [3.2 l/m per kw] for most applications of water loop heat pumps. To insure proper maintenance and servicing, P/T ports are imperative for temperature and flow verification, as well as performance checks. Cooling Tower/Boiler Systems typically utilize a common loop maintained F [16-32 C]. The use of a closed circuit evaporative cooling tower with a secondary heat exchanger between the tower and the water loop is recommended. If an open type cooling tower is used continuously, chemical treatment and filtering will be necessary. Low Water Temperature Cutout Setting - CXM or DXM Control: When an antifreeze is selected, the LT1 jumper (JW3) should be clipped to select the low temperature (Antifreeze 15 F [-9.4 C]) setpoint to avoid nuisance faults. See Figure 4: Low Water Temperature Cutout - LT1. WARNING! WARNING! Never jumper terminal A from CXM or DXM board #1 to CXM or DXM board #2 on multi-compressor/ control bound units. See Figure 5 in electrical section of this document for motorized valve wiring. CAUTION! CAUTION! Many units are installed with a factory or fi eld supplied manual or electric shut-off valve. DAMAGE WILL OCCUR if shut-off valve is closed during unit operation. A high pressure switch must be installed on the heat pump side of any fi eld provided shut-off valves and connected to the heat pump controls in series with the built-in refrigerant circuit high pressure switch to disable compressor operation if water pressure exceeds pressure switch setting. The fi eld installed high pressure switch shall have a cut-out pressure of 300 psig and a cut-in pressure of 250 psig. This pressure switch can be ordered from ClimateMaster with a 1/4 internal fl are connection as part number 39B0005N02. Air Pad or Extruded polystyrene insulation board Water Flow Control Regulator Valve P/T Plugs Boiler Drains Pressure Tank Water Out Shut-Off Valve Optional Filter Water In Thermostat Wiring climatemaster.com 11

12 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Ground-Water Heat Pump Applications Typical open loop piping is shown in Figure 3. Shut off valves should be included in case of servicing. Boiler drains or other valves should be tee d into the line to allow acid flushing of just the heat exchanger. Pressure temperature plugs should be used so that flow and temperature can be measured. Supply and return water piping materials should be limited to copper, PE, or similar material. PVC or CPVC should never be used as they are incompatible with the POE oils used in HFC-410A products and piping system failure and property damage may result. WARNING! WARNING! Polyolester Oil, commonly known as POE oil, is a synthetic oil used in many refrigeration systems including those with HFC-410A refrigerant. POE oil, if it ever comes in contact with PVC or CPVC piping, may cause failure of the PVC/CPVC. PVC/CPVC piping should never be used as supply or return water piping with water source heat pump products containing HFC-410A as system failures and property damage may result. Table 1: Water Quality Standards Water Quality Parameter HX Material Closed Recirculating Open Loop and Recirculating Well Scaling Potential - Primary Measurement Above the given limits, scaling is likely to occur. Scaling indexes should be calculated using the limits below ph/calcium Hardness Method All - ph < 7.5 and Ca Hardness <100ppm Index Limits for Probable Scaling Situations - (Operation outside these limits is not recommended) Scaling indexes should be calculated at 66 C for direct use and HWG applications, and at 32 C for indirect HX use. A monitoring plan should be implemented. Ryznar Stability Index All If >7.5 minimize steel pipe use. Langelier to +0.5 All Saturation Index If <-0.5 minimize steel pipe use. Based upon 66 C HWG and Direct well, 29 C Indirect Well HX Iron Fouling Iron Fe 2+ (Ferrous) (Bacterial Iron potential) Iron Fouling Corrosion Prevention ph Hydrogen Sulfide (H 2 S) Ammonia ion as hydroxide, chloride, nitrate and sulfate compounds Maximum Chloride Levels Erosion and Clogging Particulate Size and Erosion All All All All All - <0.2 ppm (Ferrous) If Fe 2+ (ferrous)>0.2 ppm with ph 6-8, O2<5 ppm check for iron bacteria. - <0.5 ppm of Oxygen Above this level deposition will occur Monitor/treat as Minimize steel pipe below 7 and no open tanks with ph <8 needed - <0.5 ppm At H 2 S>0.2 ppm, avoid use of copper and copper nickel piping or HX's. Rotten egg smell appears at 0.5 ppm level. Copper alloy (bronze or brass) cast components are OK to <0.5 ppm. - <0.5 ppm Maximum Allowable at maximum water temperature. 10 C 24 C 38 C Copper - <20ppm NR NR Cupronickel - <150 ppm NR NR 304 SS - <400 ppm <250 ppm <150 ppm 316 SS - <1000 ppm <550 ppm < 375 ppm Titanium - >1000 ppm >550 ppm >375 ppm All <10 ppm of particles and a maximum velocity of 1.8 m/s Filtered for maximum 841 micron [0.84 mm, 20 mesh] size. <10 ppm (<1 ppm "sandfree for reinjection) of particles and a maximum velocity of 1.8 m/s. Filtered for maximum 841 micron 0.84 mm, 20 mesh] size. Any particulate that is not removed can potentially clog components. The ClimateMaster Water Quality Table provides water quality requirements for ClimateMaster coaxial heat exchangers. The water should be evaluated by an independent testing facility comparing to this Table and when properties are outside of these requirements, an external secondary heat exchanger must be used to isolate the heat pump heat exchanger from the unsuitable water. Failure to do so will void the warranty for the coaxial heat exchanger and any other components damaged by a leak. Notes: Closed Recirculating system is identified by a closed pressurized piping system. Recirculating open wells should observe the open recirculating design considerations. NR Application not recommended Rev.: 5/6/2014 S 12 ClimateMaster Water-Source Heat Pumps

13 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Water quantity should be plentiful and of good quality. Consult Table 1 for water quality guidelines. The unit can be ordered with either a copper or cupro-nickel water heat exchanger. Copper is recommended for closed loop systems and open loop ground water systems that are not high in mineral content or corrosiveness. In conditions anticipating heavy scale formation or in brackish water, a cupro-nickel heat exchanger is recommended. In ground water situations where scaling could be heavy or where biological growth such as iron bacteria will be present, a closed loop system is recommended. It is recommended to install an intermediate heat exchanger to isolate an open loop from the heat pump loop on open well systems. Heat exchangers may over time lose heat exchange capabilities due to a build up of mineral deposits inside. These can be cleaned only by a qualified service mechanic as acid and special pumping equipment are required. In areas with extremely hard water, the owner should be informed that the heat exchanger may require occasional acid flushing. Expansion Tank and Pump - Use a closed, bladdertype expansion tank to minimize mineral formation due to air exposure. The expansion tank should be sized to handle at least one minute run time of the pump to prevent premature pump failure using its drawdown capacity rating. Discharge water from the unit is not contaminated in any manner and can be disposed of in various ways depending on local building codes; i.e. recharge well, storm sewer, drain field, adjacent stream or pond, etc. Most local codes forbid the use of sanitary sewer for disposal. Consult your local building and zoning department to assure compliance in your area. Low Water Temperature Cut-Out Setting - For all open loop systems the 35 F [1.7 C] LT1 setting (factory setting-water) should be used to avoid freeze damage to the unit. See Figure 4: Low Water Temperature Cutout - LT1. WARNING! WARNING! Never jumper terminal A from CXM or DXM board #1 to CXM or DXM board #2 on multi-compressor/ control bound units. See Figure 5 in electrical section of this document for motorized valve wiring. CAUTION! CAUTION! Many units are installed with a factory or fi eld supplied manual or electric shut-off valve. DAMAGE WILL OCCUR if shut-off valve is closed during unit operation. A high pressure switch must be installed on the heat pump side of any fi eld provided shut-off valves and connected to the heat pump controls in series with the built-in refrigerant circuit high pressure switch to disable compressor operation if water pressure exceeds pressure switch setting. The fi eld installed high pressure switch shall have a cut-out pressure of 300 psig and a cut-in pressure of 250 psig. This pressure switch can be ordered from ClimateMaster with a 1/4 internal fl are connection as part number 39B0005N02. CAUTION! CAUTION! Low temperature limit system will not allow leaving load water temperature (cooling mode) or leaving source water temperature (heating mode) to be below 42 F [5.6 C]. Water Control Valve - Note the placement of the water control valve. Always maintain water pressure in the heat exchanger by placing water control valves at the outlet of the unit to prevent mineral precipitation. Pilot operated or Taco slow closing valve s solenoid valves are recommended to reduce water hammer. If water hammer persists, a mini-expansion tank can be mounted on the piping to help absorb the excess hammer shock. Insure that the total VA draw of the valve can be supplied by the unit transformer. For instance the Taco slow closing valve can draw up to 35VA. This can overload smaller 40 or 50 VA transformers depending on the other controls employed. A typical pilot operated solenoid valve draws approximately 15VA. Flow Regulation - Flow regulation can be accomplished by two methods. First, most water control valves have a built in flow adjustment. By measuring the pressure drop through the unit heat exchanger, flow rate can be determined and compared to Tables 7 and 8. Since the pressure is constantly varying, two pressure gauges might be needed. Simply adjust the water control valve until the desired flow of 1.5 to 2 gpm per ton is achieved. Secondly, a flow control device may be installed. The devices are typically an orifice of plastic material that is designed to allow a specified flow rate. These are mounted on the outlet of the water control valve. On occasion, these valves can produce a velocity noise that can be reduced by applying some back pressure. This is accomplished by slightly closing the leaving isolation valve of the well water setup. climatemaster.com 13

14 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Ground-Loop Heat Pump Applications CAUTION! CAUTION! The following instructions represent industry accepted installation practices for Closed Loop Earth Coupled Heat Pump Systems. They are provided to assist the contractor in installing trouble free ground loops. These instructions are recommendations only. State and Local Codes MUST be followed and installation MUST conform to ALL applicable Codes. It is the responsibility of the Installing contractor to determine and comply with ALL applicable Codes and Regulations. Pre-Installation - Prior to installation, locate and mark all existing underground utilities, piping, etc. Install loops for new construction before sidewalks, patios, driveways, and other construction has begun. During construction, accurately mark all ground loop piping on the plot plan as an aid in avoiding potential future damage to the installation. Piping Installation - All earth loop piping materials should be limited to only polyethylene fusion for inground sections of the loop. Galvanized or steel fitting should not be used at any time due to their tendency to corrode. All plastic to metal threaded fittings should be avoided due to their potential to leak in earth coupled applications and a flanged fitting substituted. P/T plugs should be used so that flow can be measured using the pressure drop of the unit heat exchanger in lieu of other flow measurement means. Earth loop temperatures can range between 25 to 110 F [-4 to 43 C], and 2.25 to 3 gpm of flow per ton [2.9 l/m to 3.9 l/m per kw] of cooling capacity is recommended in these applications. Upon completion of the ground loop piping, pressure test the loop to assure a leak free system. Horizontal Systems: Test individual loops as installed. Test entire system when all loops are assembled. Vertical U-Bends and Pond Loop Systems: Test Vertical U-bends and pond loop assemblies prior to installation with a test pressure of at least 100 psi [689 kpa]. Flushing the Earth Loop - Upon completion of system installation and testing, flush the system to remove all foreign objects and purge to remove all air. Flush the loop first with the unit isolated to avoid flushing debris from the loop into the unit heat exchanger. Table 2: Antifreeze Percentages by Volume Type Methanol 100% USP food grade Propylene Glycol Ethanol* Minimum Temperature for Low Temperature Protection 10 F [-12.2 C] 15 F [-9.4 C] 20 F [-6.7 C] 25 F [-3.9 C] 25% 38% 29% 21% 25% 25% 16% 22% 20% 10% 15% 14% * Must not be denatured with any petroleum based product Antifreeze - In areas where minimum entering loop temperatures drop below 40 F [5 C] or where piping will be routed through areas subject to freezing, anti-freeze is needed. Alcohols and glycols are commonly used as antifreezes, however your local sales manager should be consulted for the antifreeze best suited to your area. Low temperature protection should be maintained to 15 F [9 C] below the lowest expected entering loop temperature. For example, if 30 F [-1 C] is the minimum expected entering loop temperature, the leaving loop temperature would be 25 to 22 F [-4 to -6 C] and low temperature protection should be at 15 F [-10 C] e.g. 30 F - 15 F = 15 F [-1 C - 9 C = -10 C]. All alcohols should be premixed and pumped from a res er voir outside of the building when possible or introduced under water level to prevent fuming. Initially calculate the total volume of fluid in the piping system. Then use the percentage by volume shown in Table 2 for the amount of an ti freeze. Antifreeze concentration should be checked from a well mixed sample using a hydrometer to measure specific gravity. Low Water Temperature Cut-Out Setting - CXM or DXM Control: When an an ti freeze is se lect ed, the LT1 jumper [JW3] should be clipped to select the low tem per a ture (An ti freeze 15 F [-9.4 C]) setpoint to avoid nuisance faults. See Figure ClimateMaster Water-Source Heat Pumps

15 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Water Control Valve - Note the placement of the water control valve. Always maintain water pressure in the heat exchanger by installing water control valves at the source out of the unit to prevent mineral precipitation. Position water high pressure switch between unit and valve. Pilot operated or slow closing valves are recommended to reduce water hammer. If water hammer persists, a miniexpansion tank can be mounted on the piping to help absorb the excess hammer shock. Insure that the total VA draw of the valve can be supplied by the unit transformer. For instance, some slow closing valves can draw up to 35VA. This can overload smaller transformers depending on the other controls employed. A typical pilot operated solenoid valve draws approximately 15VA. Flow Regulation - Install on source in of unit. Flow regulation can be accomplished by two methods. First, most water control valves have a built in flow adjustment. By measuring the pressure drop through the unit heat exchanger, flow rate can be determined and compared to Table 6. Since the pressure is constantly varying, two pressure gauges might be needed. Simply adjust the water control valve until the desired flow of 2.5 to 3 gpm per ton [2.0 to 2.6 l/m per kw] is achieved. Secondly, a flow control device may be installed. The devices are typically an orifice of plastic material that is designed to allow a specified flow rate. These are mounted on the outlet of the water control valve. On occasion, these valves can produce a velocity noise that can be reduced by applying some back pressure. This is accomplished by slightly closing the leaving isolation valve of the well water setup. WARNING! WARNING! Never jumper terminal A from CXM or DXM board #1 to CXM or DXM board #2 on multi-compressor/ control bound units. See Figure 5 in electrical section of this document for motorized valve wiring. CAUTION! CAUTION! Many units are installed with a factory or fi eld supplied manual or electric shut-off valve. DAMAGE WILL OCCUR if shut-off valve is closed during unit operation. A high pressure switch must be installed on the heat pump side of any fi eld provided shut-off valves and connected to the heat pump controls in series with the built-in refrigerant circuit high pressure switch to disable compressor operation if water pressure exceeds pressure switch setting. The fi eld installed high pressure switch shall have a cut-out pressure of 300 psig and a cut-in pressure of 250 psig. This pressure switch can be ordered from ClimateMaster with a 1/4 internal fl are connection as part number 39B0005N02. ELECTRICAL LINE VOLTAGE CAUTION! CAUTION! Use only copper conductors for fi eld installed electrical wiring. Unit terminals are not designed to accept other types of conductors. General Line Voltage Wiring - Be sure the available power is the same voltage and phase as that shown on the unit serial plate. Line and low voltage wiring must be done in accordance with local codes or the National Electric Code, whichever is applicable. TMW Power Connection - Line voltage connection is made by connecting the incoming line voltage wires to L1, L2, and L3 on power distribution block. Consult electrical data table for correct fuse size. 208 Volt Operation - All Volt units are factory wired for 208 Volt. The transformers may be switched to 230V operation as illustrated on the wiring diagram by switching the Red (208V) and the Orange (230V) at the contactor terminal L2. WARNING! WARNING! Disconnect electrical power source to prevent injury or death from electrical shock. WARNING! WARNING! To avoid possible injury or death due to electrical shock, open the power supply disconnect switch and secure it in an open position during installation. All field installed wiring, including electrical ground, must comply with the National Electrical Code as well as all applicable local codes. Refer to the unit wiring diagrams for fuse sizes and a schematic of the field connections which must be made by the installing (or electrical) contractor. Consult the unit wiring diagram located on the inside of the compressor access panel to ensure proper electrical hookup. All final electrical connections must be made with a length of flexible conduit to minimize vibration and sound transmission to the building. climatemaster.com 15

16 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Electrical - Line Voltage TMW Electrical Data Model TMW036 TMW060 B TMW120 B TMW170 TMW340 Voltage Code Voltage Voltage Min/ Max Compressor Qty RLA LRA Total Unit FLA Min Circuit Amps Max Fuse/ HACR G /60/1 187/ E 265/60/1 239/ H /60/3 187/ F 460/60/3 414/ N 575/60/3 518/ V /50/1 198/ U /50/3 342/ G /60/1 187/ H /60/3 187/ F 460/60/3 414/ N 575/60/3 518/ U /50/3 342/ G /60/1 187/ H /60/3 187/ F 460/60/3 414/ N 575/60/3 518/ U /50/3 342/ H /60/3 187/ F 460/60/3 414/ N 575/60/3 518/ U /50/3 342/ H /60/3 187/ F 460/60/3 414/ N 575/60/3 518/ U /50/3 342/ ELECTRICAL - LOW VOLTAGE Figure 4: Changing LT1-Low Water Temperature Cutout Setpoint Thermostat Connections - The aquastat/thermostat should be wired directly to the CXM/DXM board #1. Note: The TMW second stage is wired directly to the CXM #2. CXM PCB LT1 LT2 JW3-LT1 jumper should be clipped when antifreeze is used. Low Water Temperature Cutout - LT1 - The CXM/ DXM control allows the field selection of source fluid low temperature cutout points. The factory setting of LT1 is set for water (35 F [1.7 C]). In cold temperature applications jumper JW3 (LT1- antifreeze 15 F [-9.4 C]) should be clipped as shown in Figure 4 to change the setting to 10 F [-12.2 C], a more suitable temperature when using antifreezes. Never clip JW3 prior to antifreeze being added to the loop. 16 ClimateMaster Water-Source Heat Pumps

17 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Electrical - Accessories Accessory Connections - A terminal paralleling the compressor contactor coil has been provided on the CXM/DXM control of the TMW line. "A" has been provided to control accessory devices, such as water valves, electronic air cleaners, humidifiers, etc. Note: This terminal must be used only with 24 Volt signals and not line voltage signals. This signal operates with the compressor contactor. See Figure 8 or the wiring schematic for details. 24 Volt Accessory Wiring CXM/DXM Terminal Strip These terminals may be used to power 24 volt water valves on units size 036, 060 WARNING! WARNING! Never jumper terminal A from CXM or DXM board #1 to CXM or DXM board #2 on multi-compressor/ control bound units. See Figure 5 in electrical section of this document for motorized valve wiring. Figure 5: Field Wiring of 24 Volt Motorized Valve for Units Size Water High Pressure Switch NC Valve Relay 3 Coil RED VR3 NO 6 8 RED Refrigerant HP Switch Circuit #1, RED VR3 NO 2 4 RED Refrigerant HP Switch Circuit #2 VR 1 Coil VR2 Coil Notes - Disconnect red wire at refrigerant HP switch connect to N.O. contact, connect new red wire from N.O. contact to refrigerant HP switch. Valve Relay 1, 2-13B0001N01 (SPDT) VR1, VR2 Valve Relay 3-13B0004N01 (DPDT) VR3 Water High Pressure Switch NC Valve Relay 3 Coil Coil RED VR3 NO 6 8 RED Refrigerant HP Switch Circuit #1 RED VR3 NO RED 2 4 Refrigerant HP Switch Circuit #2 CXM/DXM, LONWORKS, OR MPC CONTROL OPERATION Note: See CXM AOM (part #97B0003N12), DXM AOM (part #97B0003N13), Lon Controller AOM (part #97B0013N01) or MPC Controller AOM (part #97B0031N01) on the web at climatemaster.com ALL wiring diagrams are available at climatemaster.com climatemaster.com 17

18 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Electrical - Line Voltage All field installed wiring, including electrical ground, must comply with the National Electrical Code as well as all applicable local codes. Refer to the unit wiring diagrams for fuse sizes and a schematic of the field connections which must be made by the installing (or electrical) contractor. 208 Volt Operation - All Volt units are factory wired for 208 Volt. The transformers may be switched to 230V operation as illustrated on the wiring diagram. By switching the Red (230V) and the Orange (208V) at the contactor terminal L2. Consult the unit wiring diagram located on the inside of the compressor access panel to ensure proper electrical hookup. All final electrical connections must be made with a length of flexible conduit to minimize vibration and sound transmission to the building. TMW Series Line Voltage Field Wiring Commercial Class (3 phase shown) Contactor -C L3 L2 L1 Grnd TMW120 Series Line Voltage Field Wiring Commercial Class ALL wiring diagrams available at climatemaster.com 18 ClimateMaster Water-Source Heat Pumps

19 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Electrical - Low Voltage Thermostat Connections - The aquastat/thermostat should be wired directly to the CXM/DXM board as shown in Figure 6a for TMW and Figure 6b for the TMW120. Note the TMW second stage is wired directly to the CXM #2. Figure 6a. TMW Low Voltage Field Wiring (CXM shown) Figure 6b: TMW120 Low Voltage Field Wiring (CXM shown) Contactor -CC1 Grnd L1 L2 L3 Power Distribution Block Contactor -CC L2 Contactor -CC2 Capacitor CB Transformer L1 Transformer CXM Control #1 Low Voltage Wiring CXM Control Low Voltage Connector Low Voltage Connector CXM Control #2 Low Voltage Wiring Second Stage Call (Not needed on DXM Models all low voltage wires to DXM #1) Low Voltage Connector Low Water Temperature Cutout - LT1 - The CXM/ DXM control allows the field selection of source fluid low temperature cutout points. The factory setting of LT1 is set for water (30 F). In cold temperature applications jumper JW3 (LT1- antifreeze 10 F) should be clipped as shown in Figure 7 to change the setting to 10 F, a more suitable temperature when using antifreezes. It should be noted that the extended range option should be specified to operate the TMW Series at entering water temperatures below 60 F. Figure 7: Changing LT1-Low Water Temperature Cutout Setpoint LT1 LT2 CXM Board JW3-LT1 jumper should be clipped when antifreeze is used. climatemaster.com 19

20 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 TMW Series Wiring Diagram Matrix All current 60 Hz wire diagrams can be downloaded at Model TMW TMW120 TMW170 TMW340 AUX WD TMW TMW120 Wiring Diagram Part Number 96B0223N02 96B0223N03 96B0224N01 96B0223N06 96B0223N07 96B0224N02 Electrical Control DDC Agency /60/1, 265/60/1 (TMW036 ONLY) /60/3, 460/60/3, 575/60/ /60/1 (TMW060 ONLY) /60/1, 265/60/1 (TMW036 ONLY) /60/3, 460/60/3, 575/60/ /60/1 (TMW060 ONLY) 96B0225N /60/ /60/3, 96B0225N03 460/60/3, 575/60/3 96B0225N /60/1 96B0225N06 96B0226N01 96B0226N03 96B0226N05 96B0226N08 96B0226N10 96B0226N12 96B0227N01 96B0227N03 96B0227N05 96B0227N09 96B0227N11 96B0227N13 96B0146N01 96B0146N02 96B0146N05 96B0146N /60/3, 460/60/3, 575/60/ /60/3, 460/60/3, 575/60/ /60/3, 460/60/3, 575/60/3 All CXM DXM CXM DXM CXM DXM CXM DXM CXM/DXM MPC/LON MPC/LON MPC/LON MPC/LON MPC/LON MPC/LON - LON MPC - LON MPC - LON MPC - LON MPC MPC LON MPC LON ETL 20 ClimateMaster Water-Source Heat Pumps

21 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Three Phase - TMW 170 Units with CXM Controller climatemaster.com 21

22 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Typical Wiring Diagram Three Phase - TMW 340 Units with CXM & MPC Controller 22 ClimateMaster Water-Source Heat Pumps

23 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Three Phase - TMW 340 Units with CXM Controller climatemaster.com 23

24 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Typical Wiring Diagram Three Phase - TMW 340 Units with DXM 24 ClimateMaster Water-Source Heat Pumps

25 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Three Phase - TMW 170 Units with DXM Controller climatemaster.com 25

26 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Typical Wiring Diagram Three Phase - TMW 170 Units with CXM CE 26 ClimateMaster Water-Source Heat Pumps

27 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Three Phase - TMW 170 Units with DXM CE climatemaster.com 27

28 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Typical Wiring Diagram Three Phase - TMW 340 Units with CXM Controller CE 28 ClimateMaster Water-Source Heat Pumps

29 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Three Phase - TMW 340 Units with DXM Controller CE climatemaster.com 29

30 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 Typical Wiring Diagram Three Phase - TMW 120 Units with CXM Controller 30 ClimateMaster Water-Source Heat Pumps

31 THE SMART SOLUTION FOR ENERGY EFFICIENCY Rev.: July 14, 2017 Typical Wiring Diagram Single Phase - TMW 036 Units climatemaster.com 31

32 CLIMATEMASTER WATER-SOURCE HEAT PUMPS Rev.: July 14,2017 CXM Controls CXM Control - For detailed control information, see the CXM Application, Operation and Maintenance (AOM) manual (part #97B0003N12). Field Selectable Inputs - Test mode: Test mode allows the service technician to check the operation of the control in a timely manner. By momentarily shorting the test terminals, the CXM control enters a 20 minute test mode period in which all time delays are sped up 15 times. Upon entering test mode, the status LED will flash a code representing the last fault. For diagnostic ease at the thermostat, the alarm relay will also cycle during test mode. The alarm relay will cycle on and off similar to the status LED to indicate a code representing the last fault, at the thermostat. Test mode can be exited by shorting the test terminals for 3 seconds. Retry Mode: If the control is attempting a retry of a fault, the status LED will slow flash (slow flash = one flash every 2 seconds) to indicate the control is in the process of retrying. Field Configuration Options - Note: In the following field configuration options, jumper wires should be clipped ONLY when power is removed from the CXM control. Water coil low temperature limit setting: Jumper 3 (JW3-LT1 Low Temp) provides field selection of temperature limit setting for LT1 of 30 F or 10 F [-1 F or -12 C] (refrigerant temperature). Not Clipped = 30 F [-1 C]. Clipped = 10 F [-12 C]. Air coil low temperature limit setting: Jumper 2 (JW2- LT2 Low Temp) provides field selection of temperature limit setting for LT2 of 30 F or 10 F [-1 F or -12 C] (refrigerant temperature). Note: This jumper should only be clipped under extenuating circumstances, as recommended by the factory. Not Clipped = 30 F [-1 C]. Clipped = 10 F [-12 C]. Alarm relay setting: Jumper 1 (JW1-AL2 Dry) provides field selection of the alarm relay terminal AL2 to be jumpered to 24VAC or to be a dry contact (no connection). Not Clipped = AL2 connected to R. Clipped = AL2 dry contact (no connection). DIP Switches - Note: In the following field configuration options, DIP switches should only be changed when power is removed from the CXM control. DIP switch 1: Unit Performance Sentinel Disable - provides field selection to disable the UPS feature. On = Enabled. Off = Disabled. DIP switch 2: Stage 2 Selection - provides selection of whether compressor has an on delay. If set to stage 2, the compressor will have a 3 second delay before energizing. Also, if set for stage 2, the alarm relay will NOT cycle during test mode. On = Stage 1. Off = Stage 2 DIP switch 3: Not Used. DIP switch 4: DDC Output at EH2 - provides selection for DDC operation. If set to DDC Output at EH2, the EH2 terminal will continuously output the last fault code of the controller. If set to EH2 normal, EH2 will operate as standard electric heat output. On = EH2 Normal. Off = DDC Output at EH2. NOTE: Some CXM controls only have a 2 position DIP switch package. If this is the case, this option can be selected by clipping the jumper which is in position 4 of SW1. Jumper not clipped = EH2 Normal. Jumper clipped = DDC Output at EH2. DIP switch 5: Factory Setting - Normal position is On. Do not change selection unless instructed to do so by the factory. Table 3a: LED And Alarm Relay Operations Description of Operation LED Alarm Normal Mode ON Open Normal Mode w/ups Warning ON Cycle (Closed 5 seconds, Open 25 seconds) CXM is non-functional OFF Open Fault Retry Slow Flash Open Lockout Fast Flash Closed Over/Under Voltage Shutdown Slow Flash Open (Closed after 15 Minutes) Test Mode - No Fault in Memory Flashing Code 1 Cycling Code 1 Test Mode - HP Fault in Memory Flashing Code 2 Cycling Code 2 Test Mode - LP Fault in Memory Flashing Code 3 Cycling Code 3 Test Mode - LT1 Fault in Memory Flashing Code 4 Cycling Code 4 Test Mode - LT2 Fault in Memory Flashing Code 5 Cycling Code 5 Test Mode - CO Fault in Memory Flashing Code 6 Cycling Code 6 Test Mode - Over/Under Shutdown in Memory Flashing Code 7 Cycling Code 7 Test Mode - UPS in Memory Flashing Code 8 Cycling Code 8 Test Mode - Swapped Thermistor Flashing Code 9 Cycling Code 9 -Slow Flash = 1 flash every 2 seconds -Fast Flash = 2 flashes every 1 second -Flash code 2 = 2 quick flashes, 10 second pause, 2 quick flashes, 10 second pause, etc. -On pulse 1/3 second; off pulse 1/3 second 32 ClimateMaster Water-Source Heat Pumps