Mitsubishi Heavy Industries V Multi FDC71VNX Technical Manual page 115

(24) Fan control at heating startup
(a) Starting conditions
At the start of heating operation, if the difference of setting temperature and return air temperature is 5°C or higher
after the end of hot start control, this control is performed.
(b) Contents of control
(i) Sampling is made at each minute and, when the indoor heat exchanger temperature (detected with Thi-R) is 37°C or
higher, present number of revolutions of indoor fan speed is increased by 10min
(ii) If the indoor heat exchanger temperature drops below 37°C at next sampling, present number of revolutions of
indoor fan speed is reduced by 10min
(c) Ending conditions
Indoor fan speed is reduced to the setting air flow volume when the compressor OFF is established and at 30 minutes
after the start of heating operation.
(25) Room temperature detection temperature compensation during heating
With the standard specification, the compressor is turned ON/OFF with the thermostat setting temperature. When the
thermostat is likely to turn OFF earlier because the unit is installed at the ceiling where warm air tends to accumulate, the
setting can be changed with the wired remote control indoor unit function "
turned ON/OFF at one of the setting temperature +3, +2 or +1°C in order to improve the feeling of heating. The setting
temperature, however, has the upper limit of 30°C.
Standard
Compressor
Setting temperature
Room temperature (deg)
(26) Return air temperature compensation
This is the function to compensate the deviation between the detection temperature by the return air temperature thermistor
and the measured temperature after installing the unit.
(a) It is adjustable in the unit of 0.5°C with the wired remote control indoor unit function "RETURN AIR TEMP".
• +1.0°C, +1.5°C, +2.0°C
(b) Compensated temperature is transmitted to the remote control and the compressor to control them.
Note (1) The detection temperature compensation is effective on the indoor unit thermistor only.
(27) High power operation (RC-EX3A only)
It operates at with the set temperature fixed at 16°C for cooling, 30°C for heating and maximum indoor fan speed for 15
minutes maximum.
(28) Energy-saving operation (RC-EX3A only)
It operates with the setting temperature fixed at 28°C for cooling, 22°C for heating or 25°C for auto. When fan control in
cooling/heating thermo-OFF setting is "Set fan speed", fan speed during thermo-OFF is changed to "Low". (Maximum
capacity is restricted at 80%.)
(29) Warm-up control (RC-EX3A only)
Operation will be started 5 to 60 minutes before use according to the forecast made by the microcomputer which calculates
when the operation should be started in order to warm up the indoor temperature near the setting temperature at the setting
time of operation start.
(30) Home leave mode (RC-EX3A only)
When the unit is not used for a long period of time, the room temperature is maintained at a moderate level, avoiding
extremely hot or cool temperature.
(a) Cooling or heating is operated according to the outdoor temperature (factory setting 35°C for cooling, 0°C for heating)
and the setting temperature. (factory setting 33°C for cooling, 10°C for heating)
(b) Setting temperature and indoor fan speed can be set by RC-EX3A.
(31) Auto temperature setting (RC-EX3A only)
Setting temperature is adjusted automatically at the adequate temperature the center setting temperature is 24°C by
correcting the outdoor air temperature.
-1 .
Operation
Stop
-1 +1
• -1.0°C, -1.5°C, -2.0°C
-
When it is set at +3°C
Compressor
Setting temperature
114
-
'19 • PAC-T-327
-1 .
". The compressor and the heater are
Operation
Stop
+2 +4
Room temperature (deg)