Defrosting Control, Outdoor Heat Exchanger Coil (Heating) - Sanyo SPW-T253GH56 Service Manual

2-10

Defrosting Control, Outdoor Heat Exchanger Coil (Heating)

When the outdoor temperature is low, frost may form on the outdoor heat exchanger coil.
When this occurred, the defrosting system operates. The microprocessor in the outdoor
unit monitors the relationship between the temperature of the outdoor heat exchanger coil
and the outdoor temperature so it can defrost when necessary.
Flow of Defrosting
Heating operation
No counting time for detecting
frost : 15 minutes
Detecting the frost
Stand by time for defros:
2
25 minutes
Defrosting
Release of defrosting
Time Chart for Defrosting
COMPRESSOR
SOLENOID COIL
(4 WAY VALVE)
OUTDOOR FAN
(H OR L)
INDOOR FAN
(SET SPEED)
"STANDBY"
INDICATOR
During the defrost cycle, STANDBY appears on the remote controller.
*......Cold Draft Prevention may operate occasionally
Refer to time chart.
*Minimum continuous operating time by defrosting is 48 minutes (= 15 + 8 + 25).
Occurs either when the temperature of C1 (the outdoor
heat exchanger coil) has reached 10°C or above,
or when the maximum defrosting time (9 minutes)
has elapsed.
1 MINUTE MAX. 9 MINUTES
ON
ON
ON
OFF OR LL
"STANDBY" APPEARS
Defrosting
Start
– 36 –
2. Processes and functions
OUTDOOR COIL
TEMP. C1 (°C)
Y
"RELEASE OF
DEFROSTING"
RANGE
10
OUTDOOR AIR TEMP.
-13.7 10
-3
-8
The area below the heavy line
is the frost detection area.
-20
Either continuous 8 minutes or cumulative 60 minutes
are required to detect frost in the "Frosting" range.
1 MINUTE
ON
ON
OFF
OR LL
Release of
Defrosting
(°C)
X
0441_M_S
Fig. 13
ON
ON
0442_M_S
Fig. 14
SM830034