Freeze-Up Protection Control - Daikin E-Series Service Manual

SiENBE12-620

5.10 Freeze-up Protection Control

A5
remote control
Display
Outdoor Unit LED
A
Display
Method of
Indoor unit icing, during cooling operation, is detected by checking the temperatures sensed by
Malfunction
the indoor unit heat exchanger thermistor and room temperature thermistor that are located in a
Detection
shut-down room.
Malfunction
In the cooling mode, the following conditions (A) and (B) are kept together for 5 minutes.
Decision (A) Indoor unit heat exchanger temperature ≤ –1°C
Conditions (B) Indoor unit heat exchanger temperature ≤ Room temperature –10°C
Supposed
Causes
Service Diagnosis
1 2 3 4
5 4 1 4
If the freeze-up protection control is activated 4 times continuously, the system will be shut
down.
(The 4-time counter will reset itself if any of the following errors does not occur for 60
minutes: OL, radiation fin temperature rise, gas shortage, and compressor startup.)
Wrong wiring or piping
EV malfunctioning in each room
Short-circuit
Indoor unit heat exchanger thermistor defective
Room temperature thermistor defective
A5
4
Troubleshooting
223