Outline of Control (Indoor Unit)
SiUS281811EA
134
Part 4 Functions and Control
6.8 Freeze-Up
Prevention
Freeze-Up Prevention by Off Cycle (Indoor Unit Individual Control)
When the temperature detected by the liquid pipe temperature thermistor of the indoor heat
exchanger drops too low, the unit enters freeze-up prevention control in accordance with the
following conditions, and is also set in accordance with the conditions given below. (Thermostat
OFF)
When freeze-up prevention is activated, the electronic expansion valve is closed, the drain pump
turns on and the airflow rate is fixed to L tap. When the following conditions for cancelling are
satisfied, it will reset.
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)
Concept of freeze-up prevention control
System avoids freeze-up
For comfort, system avoids unnecessary thermostat ON/OFF
For ensuring compressor reliability, system avoids unnecessary compressor ON/OFF
When freeze-up prevention control starts, system makes sure the frost is completely removed.
System avoids water leakage.
Normal operation
Start
Cancel
Liquid pipe
temperature
Start
Cancel
Normal operation
–5ºC
(23°F)
0ºC
(32°F)
+7ºC
(44.6°F)
–1ºC
(30.2°F)
t1
t2
t3
t4
0ºC
(32°F)
+7ºC
(44.6°F)
10 min.
OR
10 min.
10 min.
t > 40 minutes
Freeze-up prevention control
Forced OFF by thermostat
Freeze-up prevention control
Forced OFF by thermostat
Summary of Contents for SkyAir RZR-TA Series
Page 1: ...Service Manual Cooling Only 60 Hz Heat Pump 60 Hz RZR TA RZQ TA Series SiUS281811EA...
Page 202: ...SiUS281811EA 196 Part 6 Service Diagnosis 5 15 Fan Motor Connector Check for FTQ TA 311...
Page 323: ...SiUS281811EA Wiring Diagrams Part 7 Appendix 317 RZR18 24TAVJUA RZQ18 24TAVJUA 3D124495...
Page 327: ...SiUS281811EA Wiring Diagrams Part 7 Appendix 321 FHQ18 24 30PVJU FHQ36 42MVJU 3D048116C...
Page 328: ...Wiring Diagrams SiUS281811EA 322 Part 7 Appendix FAQ18 24TAVJU 3D114844B...
Page 329: ...SiUS281811EA Wiring Diagrams Part 7 Appendix 323 FBQ18 24 30 36 42 48PVJU 3D065984J...