York H3CE180 Installation Instructions Manual

Also see for H3CE180: User guide

Contents

FIRST STAGE OF COOLINGA call for cooling at terminal Y1 energizes relay RY1. RelayRY1 closes contacts RY1-1, energizing time delay relay 3TR.If time delay relay 3TR is satisfied as described below, it willenergize its output terminal Y2, which is connected to compres-sor 1 control module terminal M1.If the compressor 1 control module is satisfied as describedbelow, it will apply power to terminal 7 of low or high pressurelock out relay (LOR) contacts. See a description of the LORoperation below. If the LOR coil is not energized (not lockedout), the LOR contacts will be closed, energizing contactor 1M,which powers compressor 1 and condenser fan motor 1.When 1M is energized on H3CE240 units, auxiliary contact1M-AC2 is closed, powering terminal 1 for opening the stage 1solenoid in air handlers which feature a stage 1 solenoid.If the low ambient temperature switch TLA is closed, it will allowcondenser fan 2 contactor 3M to energize. TLA opens as thetemperature falls below 50 F and closes as the ambient risesabove 60 F. TLA is used on the H3CE180, not the H3CE240.Anti-short Cycle Time Delay Relays 3TR and 4TRRelay 3TR, which serves compressor 1 control, has an adjust-able low voltage lock out which is set at 20V in the factory. Thevoltage applied to 3TR must be above its lock out setting and5 minutes must elapse since the relay was last energizedbefore it will energize its output terminal Y2. Relay 4TR isidentical but it serves compressor 2 control.Compressor Control ModuleIf the compressor control module terminals L1 (or T1) and L2(or T2) have 24 V applied and the internal compressor tempera-ture lock out is inactive, the internal switch connecting M1 andM2 will be closed. M1 to M2 will open if one of the compressor’sinternal temperature sensors exceeds its limit. M1 to M2 staysopen for 30 minutes after a internal temperature limit is ex-ceeded. The 30 minute lock out may be reset prior to the 30minutes expiring by removing power to the control moduleterminals L1 and L2. During normal operation, each compres-sor control module should always be powered at the L1 and L2terminals, whether there is a call for cooling or not.Low or High Pressure Lock Out OperationIf the lock out circuit path is opened during a call for cooling,the lock out relay (LOR) coil will energize, opening LOR-1contacts and disabling all compressor operation. The lock outcircuit path is open if:• the lock out relay contacts LOR-1 are open, OR• the low pressure switch LP is open AND the lowpressure switch bypass timer contacts 1TR-1 are openOR• the high pressure switch HP is open.Once the LOR coil has been energized, it remains energized,locking out cooling operation until the call for cooling has beenremoved. When Y1 is returned to 0 volts, the LOR coil is nolonger energized, closing the LOR-1 contacts and removing thelock out.The low pressure bypass timer 1TR leaves the 1TR-1 contactsclosed upon the start of a call for cooling until its 90 second(nominal) timer has expired. This bypasses the low pressureswitch during start up. After the time delay has elapsed, 1TR-1contacts are opened, once again allowing low pressure totrigger the lock out circuit if the low pressure switch opens.START-UPCRANKCASE HEATERThe crankcase heater must be energized at least 8 hours beforestarting the compressor. To energize the crankcase heater, themain disconnect switch must be closed. During this 8 hourperiod, the system switch on the room thermostat must be“OFF” to prevent the compressor from starting.CAUTION: DO NOT ATTEMPT TO START THE COMPRES-SOR WITHOUT AT LEAST 8 HOURS OF CRANK-CASE HEAT OR COMPRESSOR DAMAGE CANOCCUR.Make sure that the bottom of the compressor is warm to thetouch to prove crankcase heater operation.PRE-START CHECKBefore starting the unit, complete the following check list:1. Have sufficient clearances been provided?2. Has all foreign matter been removed from the interior of theunit (tools, construction or shipping materials, etc.)?3. Have the condenser fans been rotated manually to checkfor free rotation?4. Are all wiring connections tight?5. Does the available power supply agree with the nameplatedata on the unit?6. Is the control circuit transformer set for the proper voltage?7. Have the fuses, disconnect switch and power wire beensized properly?8. Are all compressor hold-down nuts properly secured?9. Are any refrigerant lines touching each other or any sheetmetal surface? Rubbing due to vibration could cause arefrigerant leak.10. Are there any visible signs of a refrigerant leak, such as oilresidue?11. Is any electrical wire laying against a hot refrigerant line?INITIAL START-UP1. Supply power to the unit through the disconnect switch atleast 8 hours prior to starting the compressor.2. Move the system switch on the thermostat to the AUTO orCOOL position.3. Reduce the setting of the room thermostat to energize thecompressor.4. Check the operation of the evaporator unit per the manufac-turer’s recommendations.5. With an ammeter, check the compressor amps against theunit data plate.6. Check for refrigerant leaks.7. Check for any abnormal noises and/or vibrations, and makethe necessary adjustments to correct (e.g. fan blade(s)touching shroud, refrigerant lines hitting on sheet metal,etc.)8. After the unit has been operating for several minutes, shutoff the main power supply at the disconnect switch andinspect all factory wiring connections and bolted surfaces fortightness.OPERATION550.23-N6Y12 Unitary Products Group

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