Pulse Motor Valve (Pmv) Control - Toshiba RAS-18N3KVR-E Service Manual

Item Operation flow and applicable data, etc.
12. Pulse motor This function controls throttle amount of the
valve (PMV) refrigerant in the refrigerating cycle.
control
According to operating status of the air
conditioner, this function also controls the open
degree of valve with an expansion valve with
pulse motor.
initial position
SH control
PMV open degree control
Stop by
remote controller
Power OFF
∗ SH (Super Heat amount) =
Ts (Temperature of suction pipe of the compressor) –
Tc or Te (Heat exchanger temperature at evaporation side)
∗ PMV: Pulse Motor Valve
Starting up
Initialize
Move to
Compressor ON
Td
release control
Room temp. sensor
(Ta sensor) control
Defrost
1) When starting the operation, move the valve
once until it fits to the stopper. (Initialize)
* In this time, "Click" sound may be heard.
2) Adjust the open degree of valve by super heat
amount. (SH control)
3) If the discharge temperature was excessively
up, adjust the open degree of valve so that it
is in the range of set temperature.
(Discharge temp. control)
4) When defrost operation is performed, the
open degree of valve is adjusted according to
each setup conditions during preparation for
defrost or during defrost operation
(4-way valve is inversed.).
5) To turn off the compressor while the air
conditioner stops by control of the thermostat
or by remote controller, adjust the open
degree of valve to the setup value before stop
of the compressor.
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FILE NO. SVM-12070
Description