Control Outline - Carrier MMY-MAP0724FT9UL Service Manual

6. CONTROL OUTLINE

NO. Item
1 Pulse motor 1. PMV1, 2 control (PMV1 and 2)
valve (PMV)
1) During air conditioner operation, the pulse count of a PMV (pulse motor valve) is
control
2) During all cooling, the PMV opening is controlled on the basis of measurements
3) During all heating, the PMV opening is controlled on the basis of measurements
4) PMVs are fully closed when the air conditioner is in thermo OFF state or upon
2. PMV4 control
1) PMV4 (Pulse Motor Valve) is controlled between 0 and 500 pulses at mainly
2) PMV4 opening is controlled according to the demand capacity difference (Ton)
3) PMVs are fully closed when the air conditioner is in thermo OFF state or upon
controlled between 90 and 1000.
provided by the TL temperature sensor and the Pd pressure sensor (under cool
control).
provided by the TS and TD temperature sensors and the PS pressure sensor
(super heat control).\
being turned off normally or shut down due to an abnormality.
1000
550
500
90
45
Minimum
cooling / heating operation.
between cooling and heating operation.
being turned off normally or shut down due to an abnormality.
MAX
1000
Controlled between
90 and 1000 pulses
0
– 10
Cooling-heating demand capacity difference (Ton)
MAX
500
42
0
Cooling-heating demand capacity difference (Ton)
Mainly heating operation area
Specification outline
PMV 2
PMV 1
Maximum
SH control
2
– 2 0
Mainly cooling operation area
– 60 –
Remarks
• During all
heating, collective
heating, PMV
control may be
provided with
PMV1 alone,
operated at 45
pulses
(minimum), with
PMV2 turned off.
10