Controls At Mode Changing / Start-Up - Daikin FT25CV1A Service Manual

Control for Heat Pump Models
3.3

Controls at Mode Changing / Start-up

3.3.1 Preheating Operation
Outline Operate the inverter in the open phase with the conditions including the preheating command
(only for heat pump model) from the indoor, the outdoor air temperature .
Detail Preheating ON Condition
OFF Condition
3.3.2 Four Way Valve Switching
Outline Heat Pump Only
During the heating operation current must not be conducted and during cooling and defrosting
current must be conducted. In order to eliminate the switching sound (as the four way valve coil
switches from ON to OFF) when the cooling is stopped, the delay switch of the four way valve
must be carried out after the operation stopped.
Detail The OFF delay of four way valve
Energize the coil for 160 sec after unit operation is stopped.
3.3.3 Four Way Valve Activating Guarantee
Outline Heat Pump Only
At the beginning of the operation as the four way valve is switched, acquire the differential
pressure required for activating the four way valve by having output the operating frequency,
which is more than a certain fixed frequency, for a certain fixed time.
Detail Starting Conditions
1. When starting compressor for cooling.
2. When the operating mode changes from the previous time.
3. When starting compressor for defrosting or resetting.
4. When starting compressor for the first time after the reset with the power is ON.
3.3.4 3-Minutes Standby
Prohibit to turn ON the compressor for 3 minutes after turning it off.
(Except when defrosting. (Only for Heat Pump Model).)
3.3.5 Compressor Protection Function
When turning the compressor from OFF to ON, the upper limit of frequency must be set as
follows. (The function must not be used when defrosting (only for heat pump model).)
42
When outdoor air temperature is below 11.5°C, inverter in open phase operation starts.
When outdoor air temperature is higher than 13.5°C, inverter in open phase operation stops.
Set the lower limit frequency to 66 (model by model) Hz for 45 seconds with any conditions 1
through 4 above.
FCG 3 90
FCG 2 66
FCG 1 46
TCG 1 120
TCG 2 570
TCG 3 120
Si01-406
Functions and Control