Bard WA611 Installation Instructions Manual

Also see for WA611: Installation instructions

Contents

Bard WA611 Installation Instructions Manual Manual pdf 16 page image

Manual 2100-425Page 14START UPIMPORTANT INSTALLER NOTEFor improved start-up performance, wash the indoorcoil with a dishwasher detergent.CRANKCASE HEATERSWA611, WA70 and WA721 units are provided withcompressor crankcase heat.The WA611, WA70 and WA721 models have a bandtype heater located around the bottom of thecompressor. This heater is controlled by the crankcaseheater relay. The heater is only energized when thecompressor is not running.Some form of crankcase heat is essential to preventliquid refrigerant from migrating to the compressor,casing oil pump out on compressor start-up andpossible valve failure due to compressing a liquid.The decal in Figure 9 is affixed to all WA611, WA70and WA721 units detailing start-up procedure. This isvery important. Please read carefully.HIGH PRESSURE SWITCHThe WA611, WA70 and WA721 models are suppliedwith a remote reset high pressure switch. If tripped,this pressure switch may be reset by turning thethermostat off then back on again.THREE PHASE SCROLL COMPRESSORSTART UP INFORMATIONScroll compressors, like several other types ofcompressors, will only compress in one rotationaldirection. Direction of rotation is not an issue withsingle phase compressors since they will always startand run in the proper direction.However, three phase compressors will rotate in eitherdirection depending upon phasing of the power. Sincethere is a 50-50 chance of connecting power in such away as to cause rotation in the reverse direction,verification of proper rotation must be made. All threephase units incorporate a phase monitor to ensureproper field wiring. See the Phase Monitor" sectionlater in this manual.Verification of proper rotation must be made any timea compressor is change or rewired. If improperrotation is corrected at this time there will be nonegative impact on the durability of the compressor.However, reverse operation for over one hour mayhave a negative impact on the bearing due to oil pumpout.NOTE: If compressor is allowed to run in reverserotation for several minutes, thecompressor's internal protector will trip.All three phase ZR3 compressors are wired identicallyinternally. As a result, once the correct phasing isdetermined for a specific system or installation,connecting properly phased power leads to the sameFusite terminal should maintain proper rotationdirection.Verification of proper rotation direction is made byobserving that suction pressure drops and dischargepressure rises when the compressor is energized.Reverse rotation also results in an elevated sound levelover that with correct rotations, as well as,substantially reduced current draw compared totabulated values.The direction of rotation of the compressor may bechanged by reversing any two line connections to theunit.IMPORTANTThese procedures must be followed atinitial start-up and at any time powerhas been removed for 12 hours orlonger.To prevent compressor damage which mayresult from the presence of liquidrefrigerant in the compressor crankcase.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 the crankcase.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.7961-061FIGURE 9START-UP LABEL