Mitsubishi Electric City Multi PQHY-P72 Service Handbook page 162

(3) Dry operation
1. Indoor unit fan stop
2. Inverter output 0Hz
3. Indoor unit LEV fully closed.
4. Solenoid valve OFF
5. BC controller Solenoid valve OFF
6. BC controller
LEV fully closed
*Note 1.When the indoor unit inlet temperature exceeds 18 C [64 F], the heat source unit (compressor)
and the indoor unit fan start the intermittent operation simultaneously. When the indoor unit inlet
temperature becomes 18 C [64 F],or less, the fan always runs (at low speed). The heat source
unit, the indoor unit, and the solenoid valve operate in the same way as they do in the cooling
operation when the compressor is turned on.
*Note 2.Thermostat is always kept on during test run mode, and indoor and heat source unit intermittent
operation (ON) time is a little longer than that of normal operation.
Dry operation
4-way valve OFF
YES
Test run mode
ON
NO
Thermostat ON
NO
Suction temperature
18 C[64 F]
YES
*Note 1
1. Heat source unit (compressor)
intermittent operation
2. Indoor unit fan intermittent operations
(Synchronized with the compressor:
low speed, OFF operations)
2 3
- 153 -
Normal operation
Thermostat ON
Unit in the stopped state
*Note 2
[ VII Control ]