Service Manual

Function of FFQ Series SiUS121502E
58 Function and Control
2.3 Freeze Prevention Control
Outline When the temperature detected by liquid pipe thermistor (R2T) of the indoor heat exchanger drops
too low, the unit enters freeze prevention control in accordance with the following conditions, and is
also set in accordance with the conditions given below.
Detail Conditions for starting:
Liquid pipe temperature ≤ – 1°C (30.2°F) (for total of 40 minutes)
or
Liquid pipe temperature ≤ – 5°C (23°F) (for total of 10 minutes)
Condition for cancelling:
Liquid pipe temperature ≥ 7°C (44.6°F) (for 10 minutes continuously)
Freeze prevention control
Normal operation
10 minutes
Start Cancel
– 5˚C
(23˚F)
0˚C
(32˚F)
7˚C
(44.6˚F)
10 minutes
(R22275)
Liquid pipe
temperature