Overload Protection (Heating) - Sanyo KH2442 / CH2442 Service Manual

2-7 Overload Protection (Heating)

This function prevents the air conditioner from overloading.
147
144
140
INDOOR UNIT COIL
TEMP. (E2)
138
131
127
ELECTRONIC REF.
CONTROL VALVE
OUTDOOR FM
This chart shows how the outdoor fan speed and the electronic refrigerant control valve
react to coil temperature to keep the indoor heat exchanger coil from overloading.
When sensor E2 rises above 140°F the electronic refrigerant control valve opens at 50
steps/30 seconds until E2 falls below 138°F.
Sensor E2 is located in the middle of the indoor unit heat exchange unit.
When sensor E2 rises above 144°F, the control circuit stops the outdoor fan motor till the
temp. drops to 131°F
Fuzzy control controls the electronic refrigerant control valve.
( F)
OVERLOAD
PROTECTION
FUZZY CONTROL
OPEN
H OR M
Chart Explanations and notes
2. Processes and functions
OVERLOAD PROTECTION
OPEN
START UP
COMPENSATION
OFF
II - 9
FUZZY CONTROL
H L H OR M
1927_THS_I
Fig. 10
SM830082
Section
1
2
3
4
5