Mitsubishi Electric CITY MULTI PUHY-P200YEM-A Service Handbook page 59

(8) Refrigerant Recovery Control
Refrigerant recovery is performed to prevent refrigerant from accumulating in the stopping unit, the unit under
cooling mode and that with heating thermostat being turned off.
PU(H)Y-(P)200·250
1) Start of Refrigerant recover in Heating
Refrigerant recovery is started when all of the items
below are satisfied.
• 30 minutes has passed after finishing previous
refrigerant recovery and compressor frequency is
greater then 60Hz or Td less than 105°C or 15
minutes has passed since previous recovery was
performed and frequency is less than 60Hz and Td is
greater than 105°C.
• 15 minutes has passed from starting the
compressor.
• A1 = 0 for 3 minutes.
2) Refrigerant recovery operation in heating
• Refrigerant is recovered by opening LEV of the objective indoor units (indoor units under stop. fan, and cooling
modes, and that with heating thermostat being turned off) for 15 seconds.
LEV opening at refrigerant recovery
(Indoor unit LEV opening 500 pulse)
• The regular capacity control of the outdoor unit and the regular LEV control of the indoor unit are not applied
during refrigerant recovery operation, but are fixed with the value before the recovery operation. These controls will
be conducted one minute after finishing the recovery operation.
• Defrosting operation is prohibited during the recovery operation, and it will be conducted after finishing the recov-
ery operation.
3) Refrigerant recovery operating in cooling
Refrigerant is recovered by the opening of the indoor LEV further than the operation position for 30 seconds.
Refrigerant Recovery Control
PURY-P200·250
- Start of Refrigerant recover in Heating
• 1 minute has passed from starting the compressor.
• 30 minutes has passed after finishing previous
refrigerant recovery and compressor frequency is
greater than 60Hz or Td less than 105°C or 15
minutes has passed since previous recovery was
performed and frequency is less than 60Hz and Td is
greater than 105°C.
• Al = 0 for 3 minutes.
- There is some heating ON indoor unit
Full open the LEV of Stop mode, Fan mode and
Cooling mode indoor unit for 30 seconds.
(9) Control of outdoor unit fan and outdoor unit heat exchanger capacity control
PU(H)Y-(P)200·250·315
1) Control system
Depending on capacity required, control outdoor fan flow rate with phase control, for maintaining evaporation
temperature (0˚C) in cooling operations, and high pressure saturated temperature (49˚C) in heating operations.
2) Control
• Outdoor unit fan stops when compressor stops.
• Fan is in full operation for 5 seconds after starting.
• Outdoor unit f an stops during defrosting operations.
• Lower the fan strength upper limit to approximately 50% when performing night mode settings.
LEV opening
before change
Starts
- 58 -
Start of Refrigerant recover is Cooling
Refrigerant recovery is started when all of the items
below are satisfied.
• 30 minutes has passed after finishing previous
refrigerant recovery.
• Al = 0 for 3 minutes.
• Td is greater than 105°C or Pd is greater than 2.45
HPa and SCO is greater than 10°C.
15 seconds
Finish
- Start of Refrigerant recovery in Cooling
Refrigerant recovery is started when all of the items
below are satisfied.
• 30 minutes has passed after finishing previous
refrigerant recovery.
• Al = 0 for 3 minutes.
• Td is greater than 105°C.
- There is no heating ON indoor unit
Open the SVC for 30 seconds.