Mitsubishi Electric PQHY-P120THMU-A, Service Handbook

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[
VII
Control ]
- 166 - HWE09080 GB
1. Mode determination flowchart <PQRY>
(1) Indoor unit (cooling, heating, dry, fan mode)
Start
Remote controller
display lit off
Error mode
Error stop
Error display
Self-holding of
protection function
Error command
to heat source unit
Indoor unit
LEV fully closed.
Refer to 2-(1) for
cooling operation.
Refer to 2-(2) for
heating operation.
Refer to 2-(3) for
dry operation.
Prohibition Prohibition Prohibition
Dry display Heating display Cooling display
Dry mode Heating mode
Fan mode
Fan display
Fan operations
Operation mode
Cooling mode
Prohibition
"Blinking display on
the remote controller"
FAN stop
Breaker
turned on
Operation SW
turned on
Auxiliary heater
ON
Drain pump
ON
3-minute drain
pump ON
NO
NO
NO
NO
NO
NO NO NO NO
*Note 1
*Note 1
*Note 2
*Note 3 *Note 3 *Note 3
1. Protection function
self-holding cancelled.
2. Indoor unit LEV fully closed.
1. Auxiliary heater OFF
2. Low fan speed for
1 minute
YES
YES
YES
YES
YES YES YES
YES
Normal operation
Error
Stop
1
Prohibition
Auto COOL/HEAT
display
Automatic
cooling/heating mode
*Note 3
YES
Auto
cooling/heating mode
1 1
*Note 1. Indoor unit LEV fully closed : Opening 41.
*Note 2. The system may go into the error mode on either the indoor unit side or the BC controller or heat source unit side.
If some of the indoor units are experiencing a problem, only those indoor units that are experiencing the problem
will stop. If the BC controller or the heat source unit is experiencing a problem, all the connected units will stop.
*Note 3. If multiple indoor units are connected to a port and there is a discrepancy in the operation mode between the
indoor unit and the port, the operation will be prohibited. (Operation mode blinks on the remote controller, the
Fan stops, indoor unit LEV becomes fully closed.)