Mitsubishi Electric PURY-EP200YLM-A, Руководство по обслуживанию

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[5-2 Outdoor Unit Control ]
- 136 -
HWE1314A GB
5-2-5 Refrigerant Bypass Control
Bypass solenoid valves, which bypass the high- and low- pressure sides, perform the following functions.
(1) Bypass solenoid valve (SV1a) (ON = Open)
(2) Bypass solenoid valve (SV9) (ON = Open)
(3) Bypass solenoid valve (SV5b) (ON = Closed)
Operation
SV1a
ON OFF
When starting-up the compressor of each
outdoor unit
ON for 4 minutes.
After the restoration of thermo or 3 minutes
after restart
ON for 4 minutes.
During cooling or heating operation with the
compressor stopped
Always ON.
Exception: OFF when 63HS1-63LS is 0.2MPa[29psi] or less
After the operation has stopped ON for 3 minutes.
Exception: OFF when 63HS1-63LS is 0.2MPa[29psi] or less
During defrost operation ON
While the compressor is operating at the
minimum frequency and when the low pres-
sure (63LS) drops (3 or more minutes after
compressor startup)
When the low pressure (63LS)
drops below 0.23 Mpa [33 psi] dur-
ing cooling-only or cooling-main op-
eration.
When the low pressure (63LS)
drops below 0.38 Mpa [55 psi] dur-
ing cooling-only or cooling-main op-
eration.
When high pressure (63HS1) rises When 63HS1 exceeds
3.62MPa[525psi]
When 63HS1 is or below
3.43MPa[497psi] and 30 seconds
have passed
Operation
SV9
ON OFF
When high pressure (63HS1) rises during
the heating operation
When 63HS1 exceeds 3.50MPa
[507psi]
When SV5b is ON and the pressure
is 2.70MPa[391psi]or below
Others Always OFF
Operation
SV5b
ON (Closed) OFF (Open)
When high pressure (63HS1) rises during
the heating operation
When the pressure is 2.70MPa
[391psi] or below
When SV9 is ON and the pressure
is 3.50MPa [507psi] or more
At startup ON (Closed)
During defrost cycle ON (Closed)
When returning to normal operation after
completion of the defrost cycle
OFF (Open) for 3 minutes and goes ON (Closed)
Others Always ON (Closed)