York YU2E14YEEBMHO-X, Service Manual

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9.5.7 Outdoor unit anti-freezing protection
When T2<4
℃
for 250 seconds or T2<0
℃
, the indoor unit capacity demand will be zero and resume to normal
when T2>8
℃
and the time of protection is no less than 3 minutes.
9.5.8 Oil return
Running rules:
1. If the compressor frequency keeps lower than setting frequency for setting time, the AC will rise the
frequency to setting frequency for setting time and then resume to former frequency.
2. The EXV will keep 300p while the indoor units will keep the current running mode.
If the outdoor ambient is higher than setting frequency during the oil return, the AC quit oil return.
9.5.9 Low outdoor ambient temperature protection
When compressor is off, T4 is be lower than -35
℃
.for 10s, the AC will stop and display “LP”.
When compressor is on, T4 is be lower than -40
℃
.for 10s, the AC will stop and display “LP”.
When T4 is no lower than -32
℃
.for 10s, the unit will exit protection.
T3
Resume
Off
Decrease
Hold