Mitsubishi Heavy Industries SRK28HJ Technical Manual page 17

2) Function
a)
The indoor fan motor is controlled in accordance with the temperature of the indoor heat exchanger to send warm air
from the start.
b)
When the air flow increases at heating starting as shown below, the temperature of the indoor heat exchanger become
lower since the intake air temperature is still low. By this the fan speed is decreased. In this case, in order to prevent
excessively ON/OFF switching of the fan motor, the controlling temperature is made different from the controlling
temperature for HOT KEEP.
ndoorfanOFF Speed1
OFF Speed1 Speed2 Speed3
20
(1)
(28)
(b) HOT SPURT
1) Operation timing
When starting operation. (during start-up)
2) Function
The set temperature of the thermostat is increased by 2˚C to
stabilize the room temperature quickly. When starting heating,
since the surrounding wall and furniture is cold, if the compres-
sor is stopped by thermostat, the 3 min. delay timer operates, the temperature drops rapidly during the 3 min, and although
the thermostat has to resume operation, air conditioner would not start for those 3 min. (where marked *)
Restore the set temperature to the original value when the compressor is stopped once by the thermostat or 40 minutes have
elapsed since the operation start.
(c) HOT KEEP
1) Cold draft prevention (I)
a) Operation timing: While defrosting operation
b) Function: The indoor fan is stopped and RUN (HOT KEEP) lamp flashing.
2) Cold draft prevention (II)
a) Operation timing: When thermostat is switched to "off ".
b) Function: The indoor fan operates as shown
below, and after the passage of a period of
either 5 minutes return to thermo. Control at
speed 1 operation.
Notes (1) When the thermostat does not reset within 5 minutes, reset it by operating the indoor fan motor at speed 1.
(2) The * marked speed 1 operation shows the case in which the thermostat is switched to off. While the defrosting operation the * marked operation
are not performed.
Speed2 Speed3 Speed4
Speed4
28 33 38
Temperature of indoor heat exchanger (˚C)
Indoor
fan
motor
-
43
Setting temp.
Com-
pressor
*Approx 5 min (1)
Speed
Set fan speed Stop
2 or 3
Temperature of the indoor heat exchanger (˚C )
15
-
: http://splitoff.ru/tehn-doc.html
Note (1) When the compressor
has stopped, the indoor
fan will stop at 28˚C
Compressor stop
Stabilizing curve with
conventional unit
Stabilizing curve with
HOT SPURT.
Time
HOT
Speed
Set fan speed
1 START