Toshiba MMY-MAP0724HT6UL, Service Manual

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39
6
Control Outline
„
Outdoor unit
Item Description of operation, numerical data, and other information Remarks
1. Pulse
motor valve
(PMV)
control 1. PMV1, 2 control (PMV1 and 2)
1) During air conditioner operation, the pulse count of a PMV (pulse motor valve) is
controlled between 90 and 1000.
2) During cooling, the PMV opening is controlled on the basis of measurements
provided by the TL temperature sensor and the Pd pressure sensor (under cool
control).
3) During heating, the PMV opening is controlled on the basis of measurements
provided by the TS and TD temperature sensors and the PS pressure sensor
(super heat control).
4) PMVs are fully closed when the air conditioner is in thermo OFF state or upon
being turned off normally or shut down due to an abnormality.
2. PMV4 control (applicable only to MMY-MAP0964HT6UL, MMY-MAP1144HT6UL)
1) When using a small-capacity split-type heat exchanger (mainly a sub-heat
exchanger to a combination of a sub-heat exchanger and main heat exchanger)
during cooling, the pulse count of the PMV (pulse motor valve) is controlled
between 45 and 500.
The PMV4 opening is controlled on the basis of measurements provided by the
TE1 and TE2 temperature sensors.
2) During heating, the PMV4 may be used as a pressure-relief bypass valve by
opening it to a certain degree.
• During heating, PMV control
may be provided with PMV1
alone, operated at 45 pulses
(minimum), with PMV2
turned off.
O
pen
ing
of P
M
V1
, 2
Minimum Maximum
Minimum
Maximum
O
peni
ng o
f PM
V4