Check For Malfunction In Heating Operation - Daikin VRV Service Manual

Si30-408
2.3

Check for Malfunction in Heating Operation

When heating malfunctions, check on the following factors to specify the state of malfunction
(peculiar on site). (In order to avoid an insufficient investigation at the initial check)
· Excessively frequent defrosting operation
<At the time of normal operation, starting-up, before and after oil return operation, before
and after defrosting>
If EV opening of all indoor units are the same degree, the instruction (control) for valve opening
degree is sent from the outdoor unit.
Make sure to grasp the state by using the checker.
Troubleshooting
Cold area, Snowfall area
Low
Open type shops, offices etc.
Low
Excessively light load, short circuit in indoor unit,
erroneous selection of model
Indoor unit operation capacity, EV opening degree
Small
· Refrigerant depositing in the indoor unit not in operation
· Rising of high pressure due to excess refrigerant
Piping length, difference in vertical level
Small
Make sure that the timing of heating malfunction generation.
Outdoor temperature
Indoor temperature
· Heating overload (high pressure
· Excessively frequent defrosting operation (fan control)
· Height difference in
installation level of indoor units
· For operation with the target evaporating temperature
· Height difference between
or lower (Unbalance between load and control)
outdoor unit and indoor unit
Check Items before Troubleshooting
Hot area, urban area
High
· Operation standby due to outdoor temperature
High
stepping
Excessively heavy load,
erroneous selection of model
Large
Large pressure loss
Large
down) control
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