Functions Of Thermistors: Small Heat Pumps - Daikin Sky Air R-407C Service Manual

General Functionality
1.2

Functions of Thermistors: Small Heat Pumps

1
Locating the
thermistors
2
3
4
Functions of the
thermistors
5
2–4
The thermistors on the illustration below are used to control the system. This control secures a proper
operation and prevents problems of the unit.
Outdoor unit
The table below contains the functions of the small h/p.
Ther- Wiring
Location
mistor symbol
1 Indoor heat R2T
exchanger
2 Indoor air R1T
return
3 Outdoor heat R2T
exchanger
4 Outdoor air R1T
return
3
4
Mode Function
Cooling Freeze-up thermostat
Heating Hot start indoor fan
Peak cut-off
Cooling Thermostat control
Heating Thermostat control
Cooling Not used
Heating Frost prevention and overload prevention
Defrost initiation and termination
Cooling Low ambient control
Heating Frost prevention
Defrost initiation
ESIE02–01
Indoor unit
2
1
Part 2 – Functional Description