Perfect Aire 3PAMS18-HH-MZO2, Service Manual

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The initial open angle of the EXV depends on the
size of the indoor model. The adjustment range is
150-350p.
When the unit has been running for 3 minutes,
the outdoor unit receives the indoor units' indoor
units' capacity demand and T2 information and
then calculates their average.
After comparing each indoor unit
’s T2 with the
average, the outdoor gives the following
modification commands:
----If the T2
＞
2, the relevant valve
needs to close 16p more
----
If 2≥the T2≥ average-2, the relevant
valve’s open range remains as is
----If the T2
＜
average-2, the relevant valve needs
to open 16p more
This modification is carried out every 2 minutes.
5.4.5 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.