MrCool DIY-MULTI2-18HP230C, Service Manual

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 Product Features 3 
3.4.2 Heating mode:
HeatReturnI The difference between current limit
and shutdown current
HeatT4Zone4I Heating T4≥15°C current limit value
HeatT4Zone3I Heating 14°C>T4≥10°C current limit
value
HeatT4Zone2I Heating 9°C>T4≥6°C current limit value
HeatT4Zone1I Heating 5°C>T4 current limit value
HeatStopI
Heating stop protection current value
3.5 Indoor / Outdoor Units Communication
Protection
If the indoor units do not receive the feedback signal from
the outdoor units for 2 consecutive minutes or the outdoor
units do not receive the feedback signal from any one of
indoor units for 3 consecutive minutes, the unit ceases
operation. The unit displays the failure code.
3.6 Outdoor Unit Anti-Freezing Protection
When T2<4°C for 250 seconds or T2<0°C, the indoor unit
capacity demand is zero and resumes normal operation
when T2>8°C and the protection time is no less than 3
minutes.
3.7 Oil Return
Rules for Operation
1. If the compressor frequency continues to be lower
than the frequency set for setting time, the unit raises the
frequency to the frequency set for setting time and then
resumes with the former frequency.
2. The EXV continues at 300p while indoor units maintain
their operation.
If the outdoor ambient temperature is higher than the set
frequency during oil return, the unit stops the oil return
process.
3.8 Low Outdoor Ambient Temperature
Protection
• When the compressor is off and T4 is lower than
-35°C for 10 seconds, the unit stops and displays “LP”
or “PC 0L”.
• When the compressor is on and T4 remains lower than
-40°C for 10 seconds, the unit stops and displays “LP”
or “PC 0L”.
• When T4 is no lower than -32°C for 10 seconds, the
unit exits protection.
4. Control and Functions
4.1 Capacity Request Calculation
4.1.1 Cooling Mode:
Capacity area a b c d e f
Norm code (N) 3 2 1.5 1 0.5 0
Model 9K 12K 18K 24K
HP 1.0 1.2 1.5 2.5
Capacity request of each indoor unit = reference value *
HP * K_ fan
K_ fan: fan speed correction factor of indoor unit(Effective
for some models)
Indoor mode K_fan
Turbo C_AIR_S
High C_AIR_H
Medium C_AIR_M
Low C_AIR_L