A.O. Smith Heat Pump AWH Service Manual

Instruction ManualPRINTED 0114 318653-000PLACE THESE INSTRUCTIONS ADJACENT TO HEAT PUMP AND NOTIFY OWNER TO KEEP FOR FUTURE REFERENCE.COMMERCIAL EL

10INSTALLATION REQUIREMENTSRead all installation requirements in this manual before installation begins. The installation must conform to these instru

TABLE 2MODEL VOLTS/PHASE/HZCOMPRESSOR BLOWER MOTOR PUMP (230 VAC 1Ø)*MCA MFSRLA LRA MCC FLA HP FLA HPAWH-35 208-230/1/60 18.60 100.00 29.00 3.60 1/2 0

12Table 2 on page 11 provides the MCA (Minimum Circuit Ampacity) and MFS (Maximum Fuse Size). Use MCA to select the minimum eld wires size t

13CLOSED WATER SYSTEMSWater supply systems may, because of code requirements or such conditions as high line pressure, among others, h

14connected to the storage tank. If more than one water heating appliance is connected to the storage tank the aggregate total of all heating

15Potentially harmful fumes and vapors could be introduced into occupied spaces. See Unit Placement on page 16. STORAGE & HANDLINGHEAVY OBJE

INSTALLATIONREQUIRED ABILITYInstallation and service of the HPWH unit requires ability equivalent to that of a qualied agency in the

ELECTRICAL CONNECTIONSCORRECT POWER SUPPLY!Ensure the power supply at the job site matches thevoltage and phase listed on the HPWH rating labelbefore

15. All components in the hot water supply system must be adequately sized to meet peak water ow requirement16. When the HPWH unit is i

19DIGITAL TANK THERMOSTAT INSTALLATION1. Mount the thermostat on the storage tank jacket when or at a suitable location close to the storage tank, se

20Negative PressureDucting supply air only to an alternate location, such as the outdoors, may cause excessive negative air pressure inside

21TABLE 6METAL DUCTDUCT SIZE (INCHES)6 8 10 12 14 16 18 20 22 24MODEL CFM EXT (in WG)MAXIMUM EQUIVALENT LENGTH (FEET)AWH-35 1040 0.35 3 14 41 102 208

The list below represents some of the most critical installation requirements that, when overlooked, often result in operational problems, d

START UP23ow is decreased the temperature rise will increase and as water ow is increased the temperature rise will decrease. Because of thi

DIGITAL TANK THERMOSTATSETOUTPUTMT-511RiUPBUTTONSETBUTTONFACTORY SUPPLIED DIGITAL TANK THERMOSTAT - MODEL MT511RiLEDDISPLAYDOWNBUTTONFigure 11OPERATIO

25ROUTINE MAINTENANCEWarning: When possible, disconnect all power to the unit andfollow the prescribed lock - out/tag - out procedure to prev

26CLEANING INTERNAL INSULATIONInspect the internal insulation on a yearly basis for any microbial growth. The insulation never has to be cleaned unles

27TROUBLESHOOTINGPROBLEM POSSIBLE CAUSES CORRECTIONSHeat pump is too noisy.1. Sheet metal fasteners are loose.2. Operating vibration is transferrin

CHECKING REFRIGERANT CHARGEServicing of the refrigeration circuit must only be performed by agencies or individuals possessing Type II

CONTROL SYSTEM29CONTROL BOARDThe heart of the control system is the Control Board which is a printed circuit board (PCB) installed inside the control

TABLE OF CONTENTS3INSTALLATION ... 16Required Tools and Materials ...

30PHASE MONITORSome of the higher capacity models are equipped with Phase Monitor and Compressor Overload modules that interface with the Control Boar

WIRING DIAGRAMSNot all models are factory equipped with Phase Monitors or Compressor Overload Modules. Table 12 shows which models wi

UNIT WIRING DIAGRAMS - FUSE SIZES208/230 VAC - SINGLE PHASE - 60 HZ32

UNIT WIRING DIAGRAMS - FUSE SIZES208/230 VAC - THREE PHASE - 60 HZ: AWH-35, AWH-55 and AWH-75 only.33

UNIT WIRING DIAGRAMS - FUSE SIZES208/230 VAC - THREE PHASE - 60 HZonly. 34

UNIT WIRING DIAGRAMS - FUSE SIZES460 VAC - THREE PHASE - 60 HZ35

UNIT WIRING DIAGRAMS - FUSE SIZES460 VAC - THREE PHASE - 60 HZonly. 36

THERMOSTAT AND ACCESSORY WIRING DIAGRAMSDIGITAL TANK THERMOSTAT WIRINGThis Ambient Air Limit Thermostat temporarily disables compressor operation when

STANDARD TANK THERMOSTAT WIRING38Figure 16REMOTE AIRTEMPERATURESENSORFIELD SUPPLIEDSTANDARD TANKTHERMOSTATNOTE:TANK TEMPERATURESETTING MUST NOTEXCEED

HIGH AMBIENT AIR KIT WIRINGNote: To purchase High Ambient Air Kit contact your sales representative, distributor or call the toll free technical suppo

4SAFE INSTALLATION, USE AND SERVICEThe proper installation, use and servicing of this commercial heat pump water heater is extremely important to your

THERMOSTAT AND ACCESSORY WIRING DIAGRAMSBUILDING RECIRCULATION PUMP WIRING DIAGRAMCIRCULATING PUMP WIRING DIAGRAMFOR BUILDING RECIRCULATION TO STORAGE

4. See Closed Systems and Thermal Expansion on page 135. See Water Connections on page 17.6. If a building recirculation loop is present the circul

4. See Closed Systems and Thermal Expansion on page 135. See Water Connections on page 17.6. If a building recirculation loop is present the circul

4. See Closed Systems and Thermal Expansion on page 135. See Water Connections on page 17.6. If a building recirculation loop is present the circul

4. See Closed Systems and Thermal Expansion on page 135. See Water Connections on page 17.6. If a building recirculation loop is present the circul

4. See Closed Systems and Thermal Expansion on page 135. See Water Connections on page 17.6. If a building recirculation loop is present the circul

46LIMITED WARRANTYMODELS AWH, WH, WW, CPH COMMERCIAL HEAT PUMP WATER HEATERSA. O. Smith Corporation, the warrantor, extends the following LIMITED WARR

47Model No. Serial No. Date InstalledDealer’s NameDealer’s Address Phone No.City and State ZipF

500 Tennessee Waltz Parkway, Ashland City, TN 37015Technical Support: 800-527-1953 • Parts: 800-433-2545 • Fax: 800-644-9306www.hotwater.com

5GROUNDING INSTRUCTIONSThis heat pump water heater must be grounded in accordance with the National Electrical Code and/or local codes. These must be

Thank You for purchasing this heat pump water heater. Properly installed and maintained, it should give you years of trouble free service.Abbreviation

78. Ensure the power supply voltage and phase at the job site matches the power requirements on the HPWH rating label before installation begins.

COMPONENT REFRIGERATION CIRCUIT1) COMPRESSOR2) HOT GAS LINE3) CONDENSER / HEAT EXCHANGER4) LIQUID LINE5) THERMOSTATIC EXPANSION VALVE (TXV)6)

9TABLE 1MODEL NUMBERPERFORMANCEAIR VOLUME (CFM)WATER FLOW (GPM)DIMENSIONSWEIGHT(LBS)WATER HEATING CAPACITYCOOLING CAPACITYCOPINLET OUTLETWATER(FPT)WID