Bard WE252 Installation Instructions Manual

Contents

Bard WE252 Installation Instructions Manual Manual pdf 16 page image

Manual 2100-385BPage 14IMPORTANT INSTALLER NOTEFor improved start-up performance, wash the indoorcoil with a dish washing detergent.HIGH PRESSURE SWITCHThe WE482, WE602 and WE701 models are suppliedwith a remote reset high pressure switch. If tripped, thispressure switch may be reset by turning the thermostatoff then back on again.CONDENSER FAN OPERATIONThe condenser fan motor on 230/208 volt, one and threephase 50 Hz models must have fan motor wired on lowspeed. These models are factory wired on low speed.SERVICE HINTS1. Caution homeowner to maintain clean air filters atall times. Also, not to needlessly close off supplyand return air registers. This reduces air flowthrough 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. Check all power fuses or circuit breakers to be surethey are the correct rating.4. Periodic cleaning of the outdoor coil to permit fulland unrestricted airflow circulation is essential.SEQUENCE OF OPERATIONCOOLING ñ 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. On all 230 voltunits there is a one minute off delay on the blowermotor. 460 volt models do not have an off delay.HEATING ñ Circuit R-W1 make at the thermostatpulling in heat contact for the strip heat and bloweroperation. On a call for second stage heat, R-W2 makesbringing on second heat contactor, if so equipped.COMPRESSOR CONTROL MODULEThe compressor control module is standard on allmodels covered by this manual. The compressor controlis an anti-short cycle/lockout timer with high and lowpressure switch 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 be2 minutes 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 on break timer starts and prevents restart untilthe delay on break and delay on make periods haveexpired.During routine operation of the unit with no powerinterruptions, the compressor will operate on demandwith no delay.High Pressure Switch and Lockout SequenceIf the high pressure switch opens, the compressorcontactor will de-energize immediately. The lockouttimer will go into a soft lockout and stay in soft lockoutuntil the high pressure switch closes and the delay onbreak time has expired. If the high pressure switchopens again in this same operating cycle, the unit willgo into manual lockout condition and the alarm relaycircuit will energize. Recycling the wall thermostatresets the manual lockout.Low Pressure Switch, Bypass, and LockoutSequence (OPTIONAL)If the low pressure switch opens for more than 120seconds, the compressor contactor will de-energize andgo into a soft lockout. Regardless the state of the lowpressure switch, the contactor will reenergize after thedelay on make time delay has expired. If the lowpressure switch remains open, or opens again for longerthan 120 seconds the unit will go into manual lockoutcondition and the alarm relay circuit will energize.Recycling the wall thermostat resets the manual lockout.Alarm Relay OutputAlarm terminal is output connection for applicationswhere alarm relay is employed. This terminal ispowered whenever compressor is locked out due to HPCor LPC sequences as described.NOTE: Both high and low pressure switch controls areinherently automatic reset devices. The highpressure switch and low pressure switch cut outand cut in settings are fixed by specific airconditioner unit model. The lockout features,both soft and manual, are a function of theCompressor Control Module.START UP