50RHE 006-060 Water-Source Heat Pumps Horizontal Units TM Carrier is participating in the Eurovent Certification Programme. Products are as listed in the Eurovent Directory of Certified Products.
CONTENTS 1 - SAFETY CONSIDERATIONS ............................................................................................................................................................. 3 2 - GENERAL .............................................................................................................................................................................................. 3 3 - INSTALLATION ...............................................................................................
1 - SAFETY CONSIDERATIONS 3 - INSTALLATION Installation and servicing of air-conditioning equipment can be hazardous due to system pressure and electrical components. Only trained and qualified service personnel should install, repair, or service air-conditioning equipment. 3.1 - Check jobsite Untrained personnel can perform basic maintenance functions of cleaning coils and filters and replacing filters. All other operations should be performed by trained service personnel.
10. Provide ready access to water valves and fittings, and screwdriver access to unit side panels, discharge collar, and all electrical connections. 11. Where access to side panels is limited, pre-removal of the control box side mounting screws may be necessary for future servicing. 3.2.3 - Inspect unit To prepare the unit for installation, complete the procedures listed below: 1.
Fig. 1 - Dimensions 50RHE Overall cabinet A (width) B (depth) C (height) mm Water connections E (water out) mm Electrical knockouts J (1/2 conduit) low voltage K (1/2 conduit) ext. pump L (3/4 conduit) power supply mm Discharge connection (duct flange installed ±2.
Fig.
3.3 - Unit location The following guidelines should be considered when choosing a location for a water-source heat pump unit: • Units are for indoor use only. • Locate in areas where ambient temperatures are between 4.4°C and 37.8°C and relative humidity is no greater than 75%. • Provide sufficient space for water, electrical and duct connections. • Locate unit in an area that allows easy access and removal of filter and access panels. • Allow enough space for service personnel to perform maintenance.
3.4 - Mounting the unit 3.6 - Condensate drain Horizontal units should be mounted using the factory-installed hangers. Proper attachment of hanging rods to building structure is critical for safety (see Figs. 2 and 5). Rod attachments must be able to support the weight of the unit. See Table 1 for unit operating weights. Slope the unit toward the drain at a 6.5 mm per 300 mm pitch (see Fig. 6).
3.7 - Piping connections Depending on the application, there are three types of watersource heat pump piping systems to choose from: water loop, ground-water and ground-loop. Refer to piping section of Carrier System Design Manual for additional information. All water-source heat pump units use low temperature soldered female pipe thread fittings for water connections to prevent annealing and out-of-round leak problems which are typically associated with high temperature brazed connections.
Water supply and quantity Check water supply. Water supply should be plentiful and of good quality. See Table 2 for water quality guidelines. IMPORTANT: Failure to comply with the above required water quality and quantity limitations and the closed-system application design requirements may cause damage to the tube-in-tube heat exchanger that is not the responsibility of the manufacturer.
Fig.
Fig. 10 - Typical Aquazone Complete C control wiring (three-phase unit) PB 6 Power supply Refer to data plate Use copper conductors only Earth (GRD) 5 N (Neutral) 4 Lug LUG L2 2 L1 1 T3 T2 T1 CC G/Y Ground lug BLK L3 3 L3 Component location G/Y G/Y BLK T3 BLK CC BLK L2 T2 BLK T3 T1 Compr.
Fig.
Fig. 12 - Typical Aquazone Deluxe D control wiring (three-phase unit) PB 6 Component location Lug LUG CC T3 T2 T1 Power supply Refer to data plate E Use copper conductors only Earth (GRD) 5 N (Neutral) 4 L3 3 BR1 L2 2 L1 1 G/Y G/Y G/Y Ground lug BLK L3 T3 BLK BLK L2CC T2 BLK T3 T1 Compr.
Table 3 - Electrical data 50RHE Power supply V-ph-Hz Voltage min./max. V Compressor RLA LRA Fan motor FLA Total unit FLA Min. circuit current A Max. fuse/HACR A 006 220/240-1-50 197/254 2.3 15.0 0.4 2.7 3.2 15 009 220/240-1-50 197/254 2.7 18.8 0.7 3.7 4.5 15 012 220/240-1-50 197/254 3.9 22.2 0.7 4.5 5.6 15 015 220/240-1-50 197/254 4.2 27.0 0.9 5.9 7.1 15 019 220/240-1-50 197/254 6.8 45.0 0.9 8.6 10.5 15 024 220/240-1-50 197/254 8.2 51.0 1.6 10.
Fig. 14 - 50RHE blower speed selection 3.8.4 - PSC (permanent split capacitor) blower speed selection All water-source heat pumps are factory-set to deliver rated air flow at nominal static (37 Pa) on medium speed. Where higher static is needed, high speed can be utilised (100 to 125 Pa). Low speed will deliver approximately 85% of rated air flow (25 Pa). The PSC blower fan speed can be changed on all units by swapping wires connected to the relay contacts that control the fan (see Table 4 and Fig. 14).
3.9 - Low voltage wiring (see Fig. 15) Fig. 15 - Low voltage field wiring 3.9.1 - Thermostat connections The thermostat should be wired directly to the Aquazone control board (see Figs. 9-12). Capacitor Circuit breaker Ground 3.9.2 - Water freeze protection The Aquazone control allows the field selection of source fluid freeze protection points through jumpers. The factory setting of jumper JW3 (FP1) is set for water at -1.1°C.
4 - PRE-START-UP 5 - FIELD SELECTABLE INPUTS 4.1 - System checkout Jumpers and DIP (dual in-line package) switches on the control board are used to customise unit operation and can be configured in the field. When the installation is complete, follow the system checkout procedure outlined below before starting up the system. Be sure: 1. Voltage is within the utilisation range specifications of the unit compressor and fan motor and voltage is balanced for 3-phase units. 2.
Alarm relay setting - Select jumper 4 (JW4-AL2 dry) for connecting alarm relay terminal (AL2) to 24 VAC (R) or to remain as a dry contact (no connection). To connect AL2 to R, do not clip the jumper. To set as dry contact, clip the jumper. Low pressure setting - The Deluxe D control can be configured for low pressure setting (LP). Select jumper 1 (JW1-LP norm. open) for choosing between low pressure input normally opened or closed. To configure for normally closed operation, do not clip the jumper.
Cycle with compressor - In this configuration, the relay will be ON any time the compressor relay is on. 6 - START-UP Use the procedure outlined below to initiate proper unit start-up. Digital night setback (NSB) - In this configuration, the relay will be ON if the NSB input is connected to ground C. NOTE: If there are no relays configured for digital NSB, then the NSB and OVR inputs are automatically configured for mechanical operation.
6.2 - Scroll compressor rotation 6.4 - Unit start-up heating mode It is important to be certain compressor is rotating in the proper direction. To determine whether or not compressor is rotating in the proper direction: 1. Connect service gauges to suction and discharge pressure fittings. 2. Energise the compressor. 3. The suction pressure should drop and the discharge pressure should rise, as is normal on any start-up. NOTE: Operate the unit in heating cycle after checking the cooling cycle.
Table 9 - Typical unit operating pressures and temperatures Entering Water water flow temp. l/s per kW °C Cooling Suction pressure kPa Discharge pressure kPa Super- Subheat cooling K K Heating Water temp. Air temp. Suction rise drop pressure K K kPa Discharge pressure kPa Super- Subheat cooling K K Water temp. Air temp. drop rise K K -1 0.027 0.041 0.
6.7 - Anti-freeze 6.8 - Cooling tower/boiler systems In areas where entering loop temperatures drop below 4.4°C or where piping will be routed through areas subject to freezing, anti-freeze is needed. These systems typically use a common loop temperature maintained at 15.6 to 32.2°C. Carrier recommends using a closed circuit evaporative cooling tower with a secondary heat exchanger between the tower and the water loop.
7 - OPERATION 7.1 - Power up mode The unit will not operate until all the inputs, terminals and safety controls are checked for normal operation. NOTE: The compressor will have a 5-minute anti-short cycle upon power up. 7.2 - Units with Aquazone Complete C control 7.2.1 - Standby Y and W terminals are not active in standby mode, however the O and G terminals may be active, depending on the application. The compressor will be off. 7.2.2 - Cooling Y and O terminals are active in cooling mode.
8 - SYSTEM TEST Table 14 - C control LED code and fault descriptions System testing provides the ability to check the control operation. The control enters a 20-minute test mode by momentarily shorting the test pins (see Figs. 9-12). All time delays are reduced by a factor of 15.
Table 15 - Aquazone D control current LED status and alarm relay operations Description Status LED (Green) Test LED (Yellow) Fault LED (Red) Alarm relay Normal mode On Off Flash last fault code in memory Open Normal mode with PM ...
9.4 - Refrigerant system Verify air and water flow rates are at proper levels before servicing. To maintain sealed circuitry integrity, do not install service gauges unless unit operation appears abnormal. Check to see that unit is within the superheat and subcooling temperature ranges shown in Table 16. If the unit is not within these ranges, recover and reweigh in refrigerant charge. Regulate flow to condenser with a supply line valve.
6. Compare the subcooling temperature with the normal temperature listed in Table 9. If the measured liquid line temperature does not agree with the required liquid line temperature, ADD refrigerant to raise the temperature or REMOVE refrigerant (using standard practices) to lower the temperature (allow a tolerance of ± 1.7 K). 10 - TROUBLESHOOTING (Figs. 20 and 21 and Table 16) When troubleshooting problems with a water-source heat pump, consider the following. 10.1 - Thermistor 9.
Table 16 - Troubleshooting Fault Heating Cooling Possible cause Main power problems X X Green status LED Off Solution Check line voltage circuit breaker and disconnect. Check for line voltage between L1 and L2 on the contactor. Check for 24 V a.c. between R and C on controller. Check primary/secondary voltage on transformer. HP fault - code 2 X Reduced or no water flow in cooling High pressure Check pump operation or valve operation/setting. Check water flow adjust to proper flow rate.
Table 16 - Troubleshooting (cont’d) Fault Heating Cooling Possible cause Only compressor runs X X Thermostat wiring Solution Check G wiring at heat pump. Jumper G and R for fan operation. X X Fan motor relay Jumper G and R for fan operation. Check for line voltage across BR contacts. X X Fan motor Check for line voltage at motor. Check capacitor. X X Thermostat wiring Check Y and W wiring at heat pump. Jumper Y and R for compressor operation in Test mode.
Heating cycle analysis Dew point DEW POINT kPa °C Air AIR coil COIL Suction SUCTION °C °C COMPRESSOR Compressor Heat COAX exchanger Expansion EXPANSION VALVE valve °C Liquid line LIQUID LINE °C DISCHARGE Discharge °C kPa Water in kPa Water out Look up pressure drop in DROP Table 10 LOOK UP PRESSURE IN TABLE 10 to TO determine flow rate DETERMINE FLOW RATE Cooling cycle analysis Dew point DEW POINT kPa °C Air AIR COIL coil °C Suction SUCTION °C COMPRESSOR Compressor Heat COAX exchanger E
11 - START-UP CHECKLIST - 50RHE R-407C UNIT Customer: ___________________________________ Job name: __________________________________________________ Model No.: __________________________________ Serial No.: ____________________________________ Date: ________ I. II.
