Mitsubishi Heavy Industries FDC100VNA-W Service Manual Download

Page: 19 / 204

'19 • PAC-SM-309

(8) Thermostat operation

(a) Cooling

(i) Thermostat is operated with the room temperature control.
(ii) Thermostat is turned ON or OFF relative to the set room temperature as shown below.

(iii) Thermostat is turned ON when the room temperature is in the range of -1 < Set temperature < +1 at the start of cool-

ing operation (including from heating to cooling).

(b) Heating

(i) Thermostat is operated with the room temperature control.
(ii) Thermostat is turned ON or OFF relative to the set room temperature as shown below.

(iii) Thermostat is turned ON when the room temperature is in the range of -1 < Set point < +1 at the start of heating op-

eration (including from cooling to heating).

(c) Fan control during heating thermostat OFF

(i) Following fan controls during the heating thermostat OFF can be selected with the indoor function setting of the wired

remote control.

①

Low

fanspeed

(Factory default),

②

Set fan speed,

③

Intermittence,

④

Fan OFF

(ii) When the “Low fan speed (Factory default)” is selected, the following taps are used for the indoor fans.

・ForDCmotor:ULotap

(iii) When the “Set fan speed” is selected, it is operated with the set fan speed also in the thermostat OFF condition.
(iv) If the “Intermittence” is selected, following controls are performed:

1) If the thermostat is turned OFF during the heating operation, the indoor unit moves to the hot control and turns OFF

the indoor fan if the heat exchanger temperature sensors (both Thi-R1 and R2) detect 25°C or lower.

2) Indoor fan OFF is fixed for 5 minutes. After the 5 minutes, the indoor fan is operated at ULo for 2 minutes. In the

meantime the louver is controlled at level.

3) After operating at ULo for 2 minutes, the indoor fan moves to the state of 1) above.
4) If the thermostat is turned ON, it moves to the hot start control.
5) When the heating thermostat is turned OFF, the remote control displays the temperature detected at the fan stop and

revises the temperature later when the indoor fan changes from ULo to stop.
The remote control uses the operation data display function to display temperatures and updates values of
temperature even when the indoor fan is turned OFF.

6) When the defrost operation starts while the heating thermostat is turned OFF or the thermostat is turned OFF during

defrost operation, the indoor fan is turned OFF. (Hot keep or hot start control takes priority.) However, the suction
temperature is updated at every 7-minute.

7) When the heating thermostat is turned ON or the operation is changed to another mode (including stop), this control

is stopped immediately, and the operating condition is restored.

(v) When the “Fan OFF” is selected, the fan on the indoor unit of which the thermostat has been turned OFF, is turned OFF.

The same occurs also when the remote control sensor is effective.

Thermostat OFF

Set room temperature

Temperature drop

Temperature rise

-1

Thermostat ON

Thermostat OFF

Heater OFF