Daikin FTXS20G2V1B Service Manual page 70

SiENBE04-808_A
Detail
When the starting control (cooling :
timer for disconnection of the discharge pipe thermistor (
over, the following adjustment is made.
1. When the operation mode is cooling
2. When the operation mode is heating
Adjustment when the thermistor is disconnected
When the disconnection is ascertained, the compressor continues operation for 9 minutes and
then stops.
When the compressor stops repeatedly, the system is shut down.
3.11.7 Control when frequency is changed
When the target discharge pipe temperature control is active, if the target frequency is changed
for a specified value in a certain time period, the target discharge pipe temperature control is
canceled and the target opening of the electronic expansion valve is changed according to the
shift.
3.11.8 Target Discharge Pipe Temperature Control
The target discharge pipe temperature is obtained from the indoor and outdoor heat exchanger
temperature, and the electronic expansion valve opening is adjusted so that the actual
discharge pipe temperature becomes close to the target discharge pipe temperature. (Indirect
SH (superheating) control using the discharge pipe temperature)
The electronic expansion valve opening and the target discharge pipe temperature are adjusted
every 20 seconds. The target discharge pipe temperature is controlled by indoor heat
exchanger temperature and outdoor heat exchanger temperature. The opening degree of the
electronic expansion valve is controlled by followings.
♦ Target discharge pipe temperature
♦ Actual discharge pipe temperature
♦ Previous discharge pipe temperature
Function and Control
When the following condition is fulfilled, the discharge pipe thermistor disconnection is
ascertained.
Discharge pipe temperature + 6°C < outdoor heat exchanger temperature
When the following condition is fulfilled, the discharge pipe thermistor disconnection is
ascertained.
Discharge pipe temperature + 6°C < indoor heat exchanger temperature
20/25/35 class
(seconds) 10
(seconds) 120
(seconds) 810
SC
(Supercool)
seconds, heating : seconds) finishes, the detection
seconds) starts. When the timer is
42 class 50 class
10 10
30 30
630 630
The target discharge pipe
temperature is set as to become the
aiming SH.
The inclination does not change
depending on the operating condition.
SH
(Superheat)
Control Specification
(R10626)
58