Daikin REYQ-AATJA, Service Manual

Page: 183 / 495

SiUS372201EA Outline of Control (Indoor Unit)
Part 4 Functions and Control 176
Note(s)
9.11 Heater Control (Except FXTQ-TA Models)
Optional PCB KRP1B... is required.
The heater control is conducted in the following manner.
Normal control
While in heating, the heater control (ON/OFF) is conducted as shown below.
Overload control
When the system is overloaded in heating, the heater will be turned OFF in the following 2
manners.
1. The heater control (ON/OFF) is conducted through the liquid pipe temperature (R2T) of the
indoor unit.
2. The heater control (ON/OFF) is conducted by converting the heater temperature into the
condensing pressure equivalent saturated temperature (Tc) according to the temperature
detection through the high pressure sensor (S1NPH) of the outdoor unit.
Fan residual
operation While the heater turns OFF, in order to prevent the activation of the thermal protector, the fan
conducts residual operation for a given period of time after the heater turns OFF. (This operation is
conducted regardless of with or without heater equipped.)
Residual operation time: 100 seconds on ceiling suspended type or 60 seconds on other types
O N Set temperat u re
OFF
2˚C
(3.6˚F)
2˚C
(3.6˚F)
O N 43˚C (109.4˚F)
OFF
50˚C (122˚F)
Li qu id pipe temperat u re
O N 50˚C (122˚F) 60˚C (140˚F)
OFF
Condensing press u re
e qu i v alent sat u rated
temperat u re