MrCool DIY-MULTI2-18HP230C, Service Manual

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 Product Features 5 
4.2.2 Heating Mode
T4
21
Breeze fan speed
19
18
Supper low fan speed
16
15
Low fan speed
13
12
Middle fan speed
10
0
High fan speed
-2
Supper high fan speed
To meet T4>T4HeatLimit_ADD_3, first determine the initial
fan based on T4. After the initial fan runs for 30s, correct
the outdoor fan based on the average temperature of T2
(when the temperature enters the critical point, it takes
10s to reach the critical point to be effective). Select a
lower gear for the first gear or (super) breeze speed.
4.3 Four-Way Valve Control
• In heating mode, a four-way valve is opened.
• In defrosting, a four-way valve operates according to
the current defrosting action.
• In other modes, a four-way valve is closed.
• When the unit is switched from heating to other
modes, the four-way valve turns off after the
compressor has been off for 2 consecutive minutes.
• Failure or protection (excluding discharge temperature
protection and high/low pressure protection) causes
the four-way valve to immediately shut down.