York EHK-05G, Installation Instructions Manual

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8.4 MANUA L DEFROST MODE (For H P system only)
When MANUA L DEFROS T switch on PCB is set to “1”, system will perform as
described in section 8.3.
When the switch is set to “0”, and T3
＜
32° F , the compressor will continue running
for 40 seconds, then turns to the Defrost Mode until the defrost termination
conditions are met, per section 8.3.
Caution: Once the manual defrost cycle is complete, return the manual defrost switch
on PCB to “0”.
When JUM P switch is set to “0”:
Compressor keeps running, when
T3 is < 32 °F and last for 30 minutes.
8.3 DEFROST MODE* (For H P system only)
Defrosting condition:
When JUM P switch is set to “1”, the defrost mode will start if one of following
conditions is satisfied:
1. Compressor keeps running, when T4 is 28.4 °F and T3 is < 32 °F and last
for 40 minutes;
2. Compressor keeps running, when T4 is < 28.4 °F and T3 is < 32 °F and last
for 50 minutes.
* When defrosting actions, if the electrical heater kit is installed, the unit would deliver the Aux. heater
operation signal to the electrical heater kit.
Low pressure protection
When low pressure is
＜
21PSIG,the compressor and the outdoor fan motor
will stop running.
When low pressure is
＞
44PSIG,the compressor and the outdoor fan motor
will resume running(3 minutes delay necessary ).
In stand-by status, if low pressure protection was detected, the compressor
will not start.
If protection cycles occur four times within 30 minutes, the compressor and
outdoor fan will shut down. In this condition, the system needs to power on
T4 function:
When T4 is < 5 ° F , the compressor will stop. If the electrical heater kit is installed
in the indoor unit, the outdoor unit will send the operation signal to the indoor unit.
When T4 is > 10.4 ° F , the compressor will restart .
Defrost termination conditions:
1. The system has operated in defrost mode for 10 minutes;
once more in order to keep on working.