Service manual

48
11
Outline of Control
Outdoor Units
Other cautions
(1) Cooling operation in low ambient temperature
1) When low pressure is reduced, the freeze prevention control by the indoor unit TC sensor
may decrease the frequency.
2) When low pressure is reduced, the cooling capacity control may decrease the frequency.
3) When discharge temp. sensor value reduces below 60°C, the frequency may be increased
over the receive command from the indoor unit.
4) No. of electro-waves of the outdoor fan decreases, and a low continuous sound may be
heard when power is turned on. (This sound is not abnormal.)
(2) PMV (Pulse Motor Valve)
1) When the power is turned on, a tap sound to initialize PMV is heard. If this sound is not
heard, PMV operation error may be present. However, this sound may not be heard at a
place where outside noise takes prominence.
2) Do not remove the driving part (Head part) of PMV during operation.
3) When replacing a PMV set, never operate the unit with the “head” part removed.
4) When removing the driving part and attaching it again, push in it securely until a “click”
sound can be heard. Then, turn the power off, and turn on again.