Bard WH185 Installation Instructions Manual

Manual 2100-501Page 15 of 21START UPIMPORTANT INSTALLER NOTEFor improved start up performance, wash the indoor coilwith a dish detergent.CRANKCASE HEATERSWH242 units are provided with compressor crankcaseheat.These models have an insertion well-type heater locatedin the lower section of the compressor housing. This isa self-regulating type heater that draws only enoughpower to maintain the compressor at a safe temperature.Some form of crankcase heat is essential to preventliquid refrigerant from migrating to the compressorcausing oil pump out on compressor start up andpossible valve failure due to compressing a liquid.The decal in Figure 10 is affixed to all outdoor unitsdetailing start up procedure. This is very important.Please read carefully.SERVICE HINTS1. Caution owner/operator to maintain clean air filtersat all times. Also, not to needlessly close off supplyand return air registers. This reduces airflowthrough the system which shortens equipmentservice life as well as increasing operating costs.2. Switching to heating cycle at 75°F or higher outsidetemperature may cause a nuisance trip of the remotereset high pressure switch. Turn thermostat off, thenon, to reset the high pressure switch.3. The heat pump wall thermostats perform multiplefunctions. Be sure that all function switches arecorrectly set for the desired operating mode beforetrying to diagnose any reported service problems.4. Check all power fuses or circuit breakers to be surethey are the correct rating.5. Periodic cleaning of the outdoor coil to permit fulland unrestricted airflow circulation is essential.SEQUENCE OF OPERATIONCOOLING – Circuit R-Y makes at thermostat pullingin compressor contactor, starting the compressor andoutdoor motor. The G (indoor motor) circuit isautomatically completed on any call for coolingoperation or can be energized by manual fan switch onsubbase for constant air circulation.FIGURE 10HEATING – a 24V solenoid coil on reversing valvecontrols heating cycle operation. Two thermostatoptions, one allowing “Auto” changeover from cycle tocycle, and the other constantly energizing solenoid coilduring heating season and thus eliminating pressureequalization noise except during defrost, are to be used.On “Auto” option, a circuit is completed from R-W1and R-Y on each heating “ON” cycle energizingreversing valve solenoid and pulling in compressorcontactor starting compressor and outdoor motor. R-Galso make starting indoor blower motor. Heat Pumpheating cycle now in operation. The second option hasno “Auto” changeover position, but instead energizesthe reversing valve solenoid constantly whenever thesystem switch on subbase is placed in “Heat” position,the “B” terminal being constantly energized from R. Athermostat demand for heat completes R-Y circuitpulling in compressor contactor starting compressor andoutdoor motor. R-G also make starting indoor blowermotor.IMPORTANTTHESE PROCEDURES MUST BEFOLLOWED AT INITIAL START UP AND ATANY TIME POWER HAS BEEN REMOVEDFOR 12 HOURS OR LONGER.TO PREVENT COMPRESSOR DAMAGE WHICHMAY RESULT FROM THE PRESENCE OF LIQUIDREFRIGERANT IN THE COMPRESSORCRANKCASE:1. MAKE CERTAIN THE ROOM THERMOSTAT IS INTHE “OFF” POSITION. (THE COMPRESSOR ISNOT TO OPERATE.)2. APPLY POWER BY CLOSING THE SYSTEMDISCONNECT SWITCH. THIS ENERGIZES THECOMPRESSOR HEATER WHICH EVAPORATESTHE LIQUID REFRIGERANT IN THECRANKCASE.3. ALLOW 4 HOURS OR 60 MINUTES PER POUNDOF REFRIGERANT IN THE SYSTEM AS NOTEDON THE UNIT RATING PLATE, WHICHEVER ISGREATER.4. AFTER PROPERLY ELAPSED TIME THETHERMOSTAT MAY BE SET TO OPERATE THECOMPRESSOR.5. EXCEPT AS REQUIRED FOR SAFETY WHILESERVICING — DO NOT OPEN SYSTEMDISCONNECT SWITCH.7961-061