Equipment Operates But Does Not Provide Heating - Daikin RZQ Series FCQ20EVA Service Manual

Symptom-based Troubleshooting
2.7

Equipment Operates but does not Provide Heating

Applicable All models of TopAir series
Models
 Wrong selection of model
Supposed
 Refrigerant shortage
Causes
 Insufficient airflow in the indoor unit
 Decrease of low pressure
Troubleshooting
Caution Be sure to turn off the power switch before connecting or disconnecting connectors, or parts may be damaged.
Is the unit in
defrost mode?
NO
Measure the temperature of suction
air and discharge air.
Temperature difference = Suction air
temp. – Discharge air temp.
Temperature
difference for heating should
be between 14 and
30˚C.
NO
Is the operation
current less than specified
level?
NO
Does indoor unit
airflow rate decrease?
NO
Is the level of
low pressure lower than
normal level?
NO
81
 In addition, the following errors may be conceivable
• Insufficient compression of the compressor
• Insufficient circulation of refrigerant
• Defective electronic expansion valve
YES
YES
heat load increase after
installation of the unit?
• Wrong selection of model
• Affection of excessive fresh air into
room
YES
YES
YES
Does the
YES
NO
SiME281501E
Wait for a while.
Normal.
Normal.
Additional unit installation
should be considered.
Refrigerant shortage possibly
generates trouble.
After vacuum drying, charge
correct amount of refrigerant.
Check the each item.
• Clogged air filter
• Soiled heat exchanger
• Defective indoor unit fan motor
(Refer to troubleshooting "
Check the each item.
• Refrigerant overcharge
• Soiled heat exchanger
• Short circuit of discharge air
• Disturbing item in airflow
• Defective fan motor of outdoor
unit
(Refer to troubleshooting "
Check the each item.
• Insufficient compression of
compressor
• Insufficient circulation of
refrigerant
• Defective electronic
expansion valve
Service Diagnosis
A6
".)
E7
".)