Mitsubishi SRK52HE Technical Manual page 19

(5) Hot spurt
(a) For 40 minutes after a heating operation begins, the system runs with set temperature raised by 2ºC.
(b) In the following cases, this function is canceled and does not activate afterwards.
1) When the compressor and outdoor unit fan have been turned OFF by the thermostat going off.
2) During high pressure control operation.
(6) HIGH POWER operation ("HI POWER" button on the remote control : ON)
The system runs under the following conditions for 15 minutes without relation to the set temperature or the fan speed setting.
Indoor unit fan
Outdoor unit fan
Compressor
(7) Defrost operation
(a) Starting conditions (Defrost operation begins when all the following conditions are satisfied.)
1) 145 minutes have passed since the heating operation began. (Accumulated operation time)
245 minutes have passed since the previous defrosting operation ended. (Accumulated operation time)
3The outdoor unit heat exchanger temperature sensor is –5ºC or lower continuously for 3 minutes.
4¡The outdoor temperature = > –7°C
The difference between the outdoor temperature sensor temperature and the outdoor heat exchanger temperature
sensor temperature is = > 7ºC.
¡The outdoor temperature < –7°C
The difference between the outdoor temperature sensor temperature and the outdoor heat exchanger temperature
sensor temperature is = > –5ºC.
5 The compressor is running.(Defrost shall not be performed once the Compressor has been ON for 10 minutes.)
2) Also, the number of times the compressor goes OFF is counted, and when it reaches 10 or more times, if the conditions
in 1, 2, 3 above (except that the outdoor heat exchanger temperature sensor is –1ºC) and outdoor temperature is 3ºC
or lower, the defroster operation starts.
3) 1Less than 45 minutes since the heating operation began. (Accumulated operation time)
2Less than 45 minutes since the previous defrosting operation ended. (Accumulated operation time)
3The outdoor unit heat exchanger temperature sensor is –5ºC or lower continuously for 3 minutes.
4The difference between the outdoor temperature sensor temperature and the outdoor heat exchanger temperature sen
sor temperature is = > 12.5ºC (63 type:11ºC, 71 type:15ºC).
(b) End conditions (when either of the following conditions is satisfied)
1Outdoor heat exchanger temperature sensor: 15ºC or higher
2Defrosting operation has continued for 10 minutes.
(c) Operation of functinal components during defrosting operation
Compressor command
Indoor unit fan
RUN light
Outdoor unit fan
4-way valve
Defrost start operation 90sec.
Notes (1) Room temperature is not adjusted during the HIGH POWER operation.
Speed 10 fixed
ON
ON
ON
OFF
Hot keep
ON
OFF
Lit
Flashes
ON
OFF
30sec.
ON
OFF
Defrost operation
-
(2) Protective function will actuate with priority even during the HIGH POWER
operation.
30sec.
90sec. Operation after defrost is ended.
Normal heating operation
(defrost recovery)
Recovery
temperature
(15°C)
17
-
Hot keep
Controlled by the indoor heat
exchanger temperature
The chart at left is for reference.
Hot keep control governs operation
during heating.