Bard WA181 Installation Instructions Manual

Contents

Bard WA181 Installation Instructions Manual Manual pdf 14 page image

Manual 2100-200Page 12IMPORTANT INSTALLER NOTEFor improved start-up performance, wash the indoor coilwith a dishwasher detergent.CRANKCASE HEATERSAll units are provided with some form of compressorcrankcase heat.All single and three phase models have an insertion well-typeheater located in the lower section of the compressorhousing. This is a self-regulating type heater that drawsonly enough power to maintain the compressor at a safetemperature.Some form of crankcase heat is essential to prevent liquidrefrigerant from migrating to the compressor, causing oilpump out on compressor start up and possible valvefailure due to compressing a liquid.The decal in Figure 8 is affixed to all outdoor unitsdetailing start up procedure. This is very important.Please read carefully.SERVICE HINTS1. Caution homeowner to maintain clean air filters at alltimes. Also, not to needlessly close off supply andreturn air registers. This reduces air flow through thesystem, which shortens equipment service life as wellas increasing operating costs.2. Check all power fuses or circuit breakers to be surethey are the correct rating.3. Periodic cleaning of the outdoor coil to permit full andunrestricted airflow circulation is essential.SEQUENCE OF OPERATIONCooling—Circuit R-Y makes at thermostat pulling incompressor contactor, starting the compressor andoutdoor motor. The G (indoor motor) circuit isautomatically completed on any call for cooling operationor can be energized by manual fan switch on subbase forconstant air circulation. On all 230 volt units there is aone minute off delay on the blower motor. 460 voltmodels do not have an off delay. On a call for heating,circuit R-W1 make at the thermostat pulling in heatcontact for the strip heat and blower operation. On a callfor second stage heat, R-W2 makes bringing on secondheat contactor, if so equipped.START UPCOMPRESSOR CONTROL MODULEThe compressor control module is optional on the modelscovered by this manual. The compressor control is ananti-short cycle/lockout timer with high and low pressureswitch monitoring and alarm relay output.Adjustable Delay On Make And Break TimerOn initial power up or any time power is interrupted tothe unit the delay on make period begins which will be 2minutes plus 10% of the delay on break setting. Whenthe delay on make is complete and the high pressureswitch (and low pressure switch if employed) is closed,the compressor contactor is energized. Upon shutdownthe delay or break timer starts and prevents restart untilthe delay on break and delay on make periods haveexpired. During routine operation of the unit with nopower interruptions the compressor will operate ondemand with no delay.FIGURE 8START UP LABELIMPORTANTThese procedures must befollowed at initial start up and atany time power has been removedfor 12 hours or longer.To prevent compressor damage which mayresult from the presence of liquid refrigerantin the compressor crankcase:1. Make certain the room thermostat is in the"off" position (the compressor is not tooperate).2. Apply power by closing the systemdisconnect switch. This energizes thecompressor heater which evaporates theliquid refrigerant in the crankcase.3. Allow 4 hours or 60 minutes per poind ofrefrigerant in the system as noted on the unitrating plate, whichever is greater.4. After properly elapsed time, the thermostatmay be set to operate the compressor.5. Except as required for safety whileservicing, do not open system disconnectswitch.7961-061