Novenco Air Handling Units Climaster ZP. Maintenance Instructions

Transcription

1 Novenco Air Handling Units Climaster ZP Maintenance Instructions August 1992 Contents Page General... 2 Dampers... 3 Filters... Heating and Cooling Coils for Water... 5 Cooling Coils for Direct Expansion... 5 Electric Heating Coil... 6 Humidifier... 6 Centrifugal Fans Novax Axial Flow Fans Tellus Axial Flow Fans Motors ; 1

2 General The air handling unit type ZP is designed as a sectionalized, selfsupporting construction of insulated sheet steel panels mounted around a frame construction supported by a base frame (fig.1). Each section comprises one or several air handling components (functions). Each section is bolted to the next with airtight seals at the joints. Access to the unit takes place through inspection doors on the access side. The panels are fastened onto the section frame by means of sheet metal screws and can be removed during major servicing. This requires removal of all panels on the access side of the relevant section in specific order (fig. 2). Afterwards the panels are mounted in the reverse order and sealed inside as shown in fig. 2. The components are mounted so that they can be removed for service and maintenance. Cleaning The inner surfaces of the unit - especially in front of the filters - must be cleaned for dust and other impurities. Cleaning is carried out by means of avacuum cleaner. The same maintenance procedure is used for anti-vibration mounts. Cleaning of the individual components takes place according to the special maintenance instructions for these components. Fig. 1 Section with end panel Sealing i Section without end panel Fig. 2 At first one of the indicated side panels is removed and afterwards the other panels in order by removing the screws along top and bottom. Sealing procedure after installation of panel 1. Carefully clean all actual inner plate edges by means of an alkaline degreasing agent HP 2000 or similar, diluted with water, scale 1:lO. 2. Rinse with water until all soap remains are gone. 3. After complete drying of plate edges: Seal the actual plate joints by silicone sealing agent Perennator V23-6 or similar. Important: Installations with areas which are vulnerable to silicone (e.g. painter's workshop) must be sealed with a sealing agent without silicone Sikaflex 521 or similar, as silicone in the gaseous state can cause destruction, even in small quantities.. Smooth the joints, e.g. by means of a finger which has been dipped into soap water.

3 Leakage The sealing strips on the inspection doors must be intact. On removal and subsequent mounting of panels it is important that the packings are leakage-free. This also applies to pipe and cable entries. Check at intervals that duct connections and flexible connections are leakage-f ree. Conditions near the air handling unit Air intake against fresh air must be kept free of foreign matter. Check at regular intervals that water traps for drain at wet functions (cooling coils, humidifiers) are filled with water. Refill, if necessary. Recommended intervals (Please see under the individual components as well): General inspection: Once a month. Minor internal cleaning: First time after 1 month of operation. Afterwards every third month. Filter check: First time after 1 month of operation. Afterwards every third month. Check of remaining functions: times a year. Thorough overhaul of the entire unit: Once a year. Dampers The damper consists of a number of aluminium damper plates mounted in synthetic bearings in a frame. The damper motion takes place via a coupling plate with slots for regulating arms which have rustproof pins mounted on the individual damper shafts (fig. 3). Cleaning In practice the damper is maintenance-free, but the moving parts must be kept clean to ensure unhampered movement. This also applies to the damper plates, the edges of impact and the tightening strips of the damper plates. Wipe off with a cloth. Damper motors Damper motors are maintained ac- Connecting rod Metal connect~ng rods (ball joint) between 2 dampers, or for damper motor, must be kept clean and well greased. If the damper rod is removed during servicing, the damper motion must be re-set accurately, as too early impact on closing the damper can overload the motor and damage the damper. Regulating Moment at - 00 Pa: Air handling unit ZP-l 00 ZP-l35 ZP-l Moment Nm ZP-225 2x2013 2x15 cording t' instructions from the For coupled dampers the above values motor supplier. should be multiplied by 2. Belimo damper motors are maintenance-f ree. If another type of damper motor is used it is important to know the regulating moment. The various regulating moments are shown in the accompanying table Pivot screw Shaft extension ' l Fig. 3 Guide pin

4 Filters The air handling unit is provided with one or several of the filter types shown on this page. Fine filters of high gravimetric efficiency are often supplemented by a prefilter of the basic filter type. The filters are inserted in frames (fig. ) and fastened by means of retaining springs which press the filter frame against the tightening strip. Filters with different frame thickness can be mounted in the filter frame as the retaining springs can be fastened at varying distances from the edge of impact. Change of filter - cleaning All filters - apart from metal type filter FM which can be cleaned by washing - are disposable, and are replaced when the recommended maximum pressure loss (A p) has been reached. The type designation of the filter is indicated on the filter frame, and should be stated on orders. The pressure loss is normally indicated by means of a pressurestat or a U-tube manometer mounted on the unit opposite to the filter. If a prefilter is combined with a fine filter, use the following procedure: When the total pressure loss accross both filters exceeds 00 Pa change the prefilter. If the pressure loss above the fine filter alone exceeds 300 Pa, change this filter. Life The life of the filters depends on the operational process, but with a dust concentration ranging from low to moderate, it will be approx. 6 months. Checking of the pressure drop should take place regularly. It is advised not to extend the life by exceeding the maximum recommended pressure drop, as the air quantity and the efficiency of the system is reduced. Dust build-up in the filters can create unhygienic conditions in the system. Cleaning of metal filters Prefilter FM can be washed in lukewarm water with added wetting agent. After drying spray the filter material with a thin layer of odourless dust binding agent type "Viscosine" or similar. Final oressure loss EU 1, PERM ALU EU, AM Pa 150 Pa Panel type filter FS (synthetic) Panel type filter FM (basic filter) Pocket typ filter FG (basic filter) No. of filter units In total 9 units. Dimensions of 610x 610 mm In total units. Dimensions of module: 610 X 610 mm. In total 16 units. Dimensions of module: 610 X 610 mm. In total 20 units. Dimensions of module: 610 X 610 mm. Fig. Pocket typ filter FF (fine filter) Compact filter FF (fine filter)

5 Heating and Cooling Coils for Water As a rule heating and cooling coils for water consist of copper tubes with aluminium fins housed in a sheet steel frame. The water is supplied and discharged through headers with connections extended through the access side of the air handling unit. Cleaning The heatinglcooling coils must be kept clean of dust and foreign matter with a view to the heatinglcooling efficiency. Cleaning is effected by means of vacuum cleaning at the air inlet and, in special cases, by means of compressed air from the air outlet. Cleaning must be performed cautiously, as the aluminium fins are vulnerable to damaae. avoid formation of algae. The water trap must be filled with water, (please see under General). In units with high air velocities an eliminator mat is mounted after the cooling coil to catch droplets. The eliminator mat can be pulled out for cleaning. Other components Components within the pipework system for regulation and ventilation and other components essential for the operation of the heating/cooling coils must be maintained in accordance with the instructions and their proper function must be checked at regular intervals. Removal -. of heating - - If the filters of the ;nit are main- and cooling coils tained according to the instructions, the cleaning interval will be every 3rd year, but more frequent examination is recommended. Cooling coils The cooling coils are supplied with a drip pan with drain for condensate, extended through the access side. The drip pan, as well as the drain hole, must be kept clean to If, during repair of the heatinglcooling coils, it is necessary to disassemble and later assemble pipe connections, headers with threaded connections must be retained to avoid distortion and leakage of the copper tubes of the heatinglcooling coils. When work has been carried out the pipework system must be cleaned. Cooling coils for direct expansion The same maintenance procedures should be adopted as for water cooling coils, supplemented with the cooling supplier's maintenance instructions for the pipe system and associated components.

6 Electric Heating Coil The electric heating coil is composed of stainless steel tubular heating elements housed in a sheet steel frame provided with a terminal box with the necessary cable inlets. Maximum thermostat The heating coil is provided with an adjustable maximum thermostat with a setting ranging from 30 to 110 C. After cutting out the maximum thermostat has automatic reset. Overheat thermostat The safety thermostat has a fixed setting of 1 10 C. In a totally automatic control system which releases the system "stop" when the overheat thermostat cuts out, the system must be re-started manually on the control panel after reset of the overheat thermostat. In case of repeated overheat cutouts, contact a service engineer immediately. Inspection of overheat thermostatat Once a year check the overheat thermostat according to the following procedure: - Set the maximum thermostat to 110 C. - Check cut-out of both thermostats. If either thermostat fails to cut out, contact a service engineer. Faint smell of burning on commissioning - mostly due to dust build-up on the heating elements after a long period of system stop. It will normally disappear quickly. Otherwise, check the electric heating coil thoroughly and check the function of the overheat thermostat. Humidifier The humidifier is the wash type humidifier composed of a frame construction with a humidifier mat of Glasdek and a water reservoir. The reservoir is provided with connection for entering water which is controlled by a float valve as well as overflow and drain connection (fig. 3). Washing is effected by means of a circulation pump in the reservoir with hose connections to the distributing pipes above the humidifier unit. Certain installations have direct water supply without circulation pump (fig. ). Here the water supply is regulated by means of a constant flow valve. Check-up and cleaning The humidifier should be checked times and cleaned at least twice a year. In case of high content of calcium and bicarbonate in the water or high dust content in the air, check the humidifier more frequently.

7 Check that - the humidifier mat is evenly moist on both sides. If not, clean the water system and the distributing pipe above the mat. - there is full flow through the entering and draining valve. If not, clean the valves and reset to original setting. - that the humidifier mat and reservoir are clean. If not, clean them. Note: The wet humidifier mat must be handled with care. - that the water level in the reservoir is correct and that the float is free of scaling. - that the water trap is filled. - that there is no salt precipitation on the front or back of the humidifier. If salt precipitation exists, increase the drainage by 25% (fig. 5). - that there is no algae growth. If there is, flush the entire humidifying system with an algae killing agent, and afterwards flush thoroughly with clean water. Pump Type of pump: PRA 7D-0 Voltage: V. Current: 0.71/0.1 A. Output: 0.1 kw. 50 Hz: 2880 r.p.m. Class B: IP 5. Deliv overflow vessei lnlet Shut-off value Water filter (if necessary) External solenoid valve (r Constant flow valve Humidifier housing Outlet Water trap - by regulating screw Fig. 5. lnlet and outlet for circulation water ~t included in the supply Fig. 6. lnlet and outlet for direct water supply Comprehensive inspections Stop the pump and let the fan run for approx. 30 min. until the humidifier mat is dry. Downtime periods At planned system stops, e.g. in holiday periods, empty and clean the water reservoir. If the humidifier is to be out of operation for some time, the humidifier mat should be removed, cleaned and stored in a protected place. Drain valve Fig. 7. Adjustment of drain quantity

8 Cleaning of Humidifier Mats and water reservoir 1. Unscrew the hose couplings. 2. Loosen, and remove the mats mounted in the air stream. 3. Remove the overflow vessel and clean the reservoir. - Flush with clean water. Distribution pipes above mat When the mat has been pulled out, there is easy access to the distribution pipe. 1. Unscrew the clamping ring. 2. Lift the distribution plate. 3. Remove the distributing pipe from the distribution plate and dismantle the plugs in the pipe.. Clean the holes of the pipe by means of an awl or the like and flush the pipe.

9 Calculation of Water Renewal (draining quantity) Due to evaporation the mineral concentration in the circulating water will go up, and consequently fresh water must be supplied constantly. The water renewal is regulated by setting the draining valve (fig. 5) and is determined by the evaporation, the ph value of the water and the concentration of calcium and bicarbonate (the composition ca2* - HCOS - CO3 2-). The ph value should not be lower than 5 and not higher than 10. The composition may cause precipitation of lime which will reduce the function and life of the humidifier. The risk will increase at high ph value and high content of calcium and bicarbonate. In the event of a major water renewal it may be worth while pretreating the water to minimize the water consumption. Mostly, the draining quantity is below 10 l/min. For desalinated water the draining should be set to a low value, often less than 5% of evaporated water quantity. Example Given: Air quantity = l.g m3/s. x2 - XI X2 - XI = r) X (xrnax - XI), = kg waterlkg dry air. where r) - humidifying efficiency. XI = water content of entering air x2 = water content of leaving air On determination of x2 - XI do not pay any attention to high values of short duration. B Necessary draining rate B = E X q X (x2 - XI) X 60 l/min, where E is evaporated water quantity kgls og q = air quantity kgls. E - q X (~2 - XI) kg/s. E = 1.9 X 1.2 X kgls. B From the table below can be read E = 0.3. B = 0.3 X 1.9 X 1.2 X 0.00 X 60 = 0.16 Ilmin. Necessary water renewal D - E X 60 + B D = 0,009 X Ilmin. Water analysis: ph = 7.1 Calcium ca2+ = 100 mg/l Bicarbonate HCOS mg/l The water quality is determined on the basis of an analysis or information from the local water company. 0 Unsuitable Directly supplied water 6 7 8

10 Centrifugal Fans The fan is a belt driven, double inlet centrifugal fan with motor and fan mounted on a common base frame. The fan can be provided with inlet vane control gear for regulation of the air quantity. The control gear is operated by a servomotor. General inspection and maintenance Before working on the fan, isolate the electrical supply at the maintenance switch and lock the switch. Twice a year check the belt condition and the operation of the fan, e.g. whether there are abnormal sounds or vibration from the machinery. If necessary, tighten the belts, (please see the separate paragraph). Vibration may be due to dust buildup on the impeller and will generally stop after cleaning. If not, check the bearings and impeller balance. (Please see separate paragraph). If the fan is provided with inlet vane control gear check the correct function of this, including whether the motion of the control gear follows the motion of the servomotor. If not, adjust the connecting rod. The correct belt tension is checked by means of a tension tester (fig. 8) and is defined in the table as the ratio between the deflection of the belts dependent on the pressure, the shaft distance between the belt pulleys and the diameter of the smallest pulley (fig. 9). All belts must have the same tension. Before tension of the belts loosen the motor and pull it from the fan, then tighten the motor loosely. Check belt tension, parallelism and alignment (fig. 1 O), and fasten the motor firmly. When changing belts the entire set of belts must be replaced. Remove the belt guard and loosen the motor sufficiently so that the belts are easy to remove. Never force the belts across the belt pulley! Mount the new belts and tighten according to the above-mentioned procedure. After half an hour of operation recheck the belt tension, and if necessary re-tighten the belts. Finally refit the belt guard. Fig. l 0 The motion of the servomotor must not exceed the motion of the inlet vane control gear. Belt tension and belt change The belt drive is designed for 25,000 hours' of operation provided the tension and alignment are correct. After this period both belts and belt pulleys are changed. Belt profile SPB XPB Diameter of smallest pulley mm > > > 355 > > > 355 Normal tension each belt in f 75 N 75 N Belt deflection per 1000 mm shaft distance New belts 25.5 mm 22.2 mm 21.0 mm 22.0 mm 18.5 mm 17.5 mm This table gives maximum belt capacity and maximum load of shaft. Re-tension 31.8 mm 27.8 mm 26.2 mm 27.5 mm 23.1 mm 21.9 mm ~eflection ---- a = Shaft distance Fig. 8 Fig. 9

11 Bearings All the bearings are deep groove Interval Quantity Fan Bearing housinglbearing ball bearings embedded in pede- hours 9 stal housings provided with grease TLZ- 710T INA PASE 50 (SKF SY 50 FM) nipples. TLZ- 800T INA PASE 50 (SKF SY 50 FM) The bearing housings can be one TLZ- 900T INA PASE 60 (SKFSY 60 FM) TLZ- 1 OOOT INA PASE 60 (SKF SY 60 FM) piece and must be changed together with the bearing, or they T-HLZ- 710T INA PASE 50 (SKF SY 50 FM) can be split where only the bearing T-H LZ- 800T INA PASE 50 (SKF SY 50 FM) T-H LZ- 900T INA PASE 60 (SKF SY 60 FM) is changed. T-HLZ-1000T INAPASE60(SKFSY60FM) The table comprises fan types, HLZ- 710T SKF 1313K/C3 + SNH 613 TG bearings, greasing intervals and HLZ- 800T SKF 1313K/C3 + SNH 613 TG grease quantities. Alternative H LZ- 900T SKF 2313K/C3 + SNH 613 TG bearings are stated in brackets. In- H LZ- 1000T SKF 2313K/C3 + SNH 613 TG tervals and grease quantities are for normal operating conditions according to the stated formula. Formula for re-greasing interval: At higher bearing temperature than Recommended types of grease: 70 C or operation under abnormal Shell Alvania No. 3, Esso Beacon 1x 106 conditions the re-greasing interval or similar as stated on the label on t = K (-l -d the fan. nx d may be reduced after consultation t = Re-greasing interval (h) with Novenco in each case conn = speed (r.p.m.) sidering the actual operating cond = inner bearing diameter (mm) ditions. K = Constant = l0 Change of belt pulleys If the fan speed is to be increased Clean the shaft, and then the entire Tighten and align the belt drive after installation the motor power bush unit and pulley are pushed (please see the paragraph Belt must be established in order to cal- back onto the shaft. Tighten the Tension and Belt Change). If the culate the maximun fan speed. bush screws firmly. belts are to be changed, check the Loosen the motor and remove the tension after half an hour of operbelts. ation and readjust if necessary. Never use a hammer for removal or mounting of belt pulleys. Mount the belt pulley by means of a Taper-lock bush (fig. 1 l), and remove the screws (1) of the bush. One of the screws is fitted in the threaded hole of the bush (15) and is turned so the bush and hub are loosened. Afterwards pull off the unit from the shaft. Clean the hole of the new pulley and the inner and outer side of the bush. Lubricate the screws (1) slightly with oil and place them loosely in the threaded holes. Fig. 11

12 Change of Bearings - Change of Fan lmpeller Before changing the bearings, re- The bearing is mounted on a split under the section re Change of lease the belt drive and remove the bush. Turn up the tab of the locking V-belt Pulley) check the symmetric belt pulley according to the same ring and loosen the nut of the split location of the fan impeller and the procedure as that for changing of bush a few turns. clearance of the fan casing by turn- V-belt pulleys. Release the lower part of the bear- ing it manually. The bearings are changed one at a time. Bearings in one piece housings Support the shaft and mark up the location of the bearing housing on the shaft. Loosen the cup point screws in the eccentric locking ring ing housing and pull the shaft with bearing housing a few millimetres away from the supporting frame. Knock loose the cone from the bearing by means of a hammer and mandrel, and withdraw the bearing from the shaft together with the lower part of the bearing housing. - Change of fan impeller (unusual) Before change of the fan impeller it will be necessary to remove some of the side panels of the air handling unit (see fig. 2, page 2). First remove the belt drive (see the special section) and support the shaft on both sides. of the bearing. Knock loose the Mounting: After removal of the locking ring by-means of a mandrel bearing clean out old grease in the Then release both bearings from and pull it from the shaft. bearing housing and check the the supporting frames, and remove Release the entire unit of bearing sealing strips, if necessary, replace the supporting frame on the access and housing from the base and pull them. side from the fan casing. it from the shaft, e.g. by using a Then push the sealing rings, split Remove the inlet cone from the fan lubricating agent. Do not use a bush and the new bearing into the casing on the access side. If the fan hammer. shaft together with the lower part of is provided with inlet vane control Position the new bearing unit, attach the bearing housing to the base, and by means of a mandrel knock the locking ring in the direction of rotation of the fan into the correct position and fasten the locking pins. Repeat this procedure for the opposite bearing. After re-establishment of belt drive (see the section re Change of Belt Pulley) check the symmetric location of the fan impeller and the clearance of the fan casing by turning manually. Bearings in split bearing housings the bearing housing which is located according to the markingout. The nuts and screws are mounted without tightening them. Mount the locking washer and nut on the split bush, and tighten the screw manually until the shaft, split bush and bearing are in proper contact with each other. Now position the shaft in the lower part of the bearing housing. Knock the nut of the split bush 5 tabs forward by means of a hammer and mandrel and lock it. Fill grease into the bearing housing (type: see table for re-greasing). Mount and fasten the upper part of the bearing housing, and afterwards fasten the bearing - housing - gear, remove the control gear on both sides first. Pull out the entire unit consisting of bearings, shaft and fan casing through the access side and place the unit on a trestle. Then remove the bearing on the access side.(see the section regarding Change of Bearings). Mark up carefully the location of the fan impeller on the shaft and loosen the locking screw on the hub of the impeller. Now pull off the impeller from the shaft by means of a wheel puller. Mount the new fan impeller in the reverse order. Removal: Support the shaft, and onto the base. Important: Check that the position mark up the location of the bearing Repeat the procedure for the oppo- of the impeller in the casing is comhousing on the shaft, after which site bearing. pletely symmetrical. the upper part of bearing housing is removed. After reassembly of belt drive (see

13 Novax Axial Flow Fans The fan consists of a cylindrical casing with inlet cone, an axial impeller, and flange mounted motor suspended in the inlet cone. The inlet cone is provided with a wire guard. The fan blades are either made of aluminium or synthetic material and are mounted between 2 hub shells which are bolted together. The fan is provided with downstream guide vanes and a diffuser with an internal flexible connection to the outlet panel of the air handling unit. The fan is mounted on feet and anti-vibration mounts. Before working on the fan isolate the electrical supply at the maintenance switch, then lock the switch. Vibrations If vibration occurs it is mostly due to dust build-up on the fan blades and will normally stop after cleaning. If there is still vibration, call a service engineer. Motors Normally, motors only require maintenance as indicated on page 1. Service of motors Isolate the electrical supply and disconnect the motor cable. Ar- range for support of motor, fan casing, downstream guide vanes and diffuser. Afterwards remove the mounting feet at the inlet cone. Separate the fan unit from the guide vane arrangement. Remove the centre screw and centre disc of the impeller. Remove the impeller by means of a wheel puller which is fitted in the 2 threaded holes of the hub then remove the wire guard and motor. After service has been carried out reassemble the parts in the reverse order. Check that the intermediate disc below the motor flange is positioned correctly and that the motor shaft is adjusted concentrically in the fan casing prior to tightening the bolts. Mount the fan impeller on the motor shaft by means of a pull-on tool which is fitted in the threaded hole of the motor shaft. Tighten the hub of the impeller to be flush with the shoulder of the motor shaft. The tip clearance between the impeller blades and the fan casing must be the same on the entire circumference, if necessary, adjust the suspension. Finally, mount the centre disc and the centre screw, assemble the fan with the guide vane arrangement, and install the mounting feet and wire guard. Connect electricity, and check the direction of rotation (indicated by the direction arrow on the casing). Important: Do not expose the individual parts of the fan to bumps or any other damage. Adjustment of blades The design of the impeller makes it possible to obtain different performances within the duty range of the fan by adjusting the blade angle. Please contact Novenco Hevac before any such adjustment. Tellus Axial Flow Fans with Variable Pitch Blades Units provided with Tellus axial flow fans are supplied with separate maintenance instructions, which must be followed strictly.

14 Electro motors Normally, electro motors do not require any other maintenance than cleaning and lubrication of the bearings and ordinary cleaning. Dismounting of motors and removal of bearings should only be performed by skilled personnel. Motors without lubricating device The bearings are installed so that they are protected against entrainment of dust and moisture. The bearings are normally greased for approx. 10,000 hours of operation and cannot be re-greased during operation. After 10,000 operating hours or max. 3 years of operation remove the bearings and clean out old grease and dirt. Dissolve the old grease in white spirit, anhydrous petroleum or leadless petrol. Afterwards fill the bearings 2/3 with high-quality lithium grease, penetration class 2 (e.g. SKF Alfalub LGMT-2). Excess filling may cause overheating of the bearings. Motors with lubricating device The bearings are provided with force feed nipples and bearing covers with grease valves and must be re-greased with highquality lithium grease, penetration class 2 (e.g. SKF Alfalub LGMT-2) at intervals as indicated in the following table. At re-greasing apply so much grease that clean grease is visible in the grease valve. Remove surplus grease. To avoid excess filling of the bearings, greasing should be carried out while the motor is in operation. Even though the bearings are regreased at the prescribed intervals, check them at suitable intervals, e.g. every third year, remove and clean as described in the previous paragraph regarding motors without lubricating device. Re-greasing intervals in months No. of revolutions r.p.m. Daily operating time Motor size

15 NOVENCO Novenco Hevac Ydernaes DK-700 Naestved Tel. (+5) Denmark Fax (+5)