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LP-532 REV. 8.13.2014
LP-532 REV. 8.13.2014
Description/Part #
Main Control Board / 7850P-058
Check Point
(Main PCB)
N/A
Function
This part controls all components contained in the water heater
Failure Event
Abnormal main controller operation.
Effects
When the main controller has abnormal condition, components may not operate
properly.
Error Code
Er 38
Diagonostic
Check each connection and/or wires damage on the PCB
Color / Wire Number
N/A
Exhaust temperature Sensor
Water inlet temperature sensor
Heat Exchanger temperature
Water outlet temperature sensor
NO
Item
Standard
1
Temperature –
Resistance Type
Idling Condition
Temperature(
℃
)
Resistance(k
Ω
)
0 ± 0.1
℃
-10.99
25 ± 0.1
℃
-3.906
85 ± 0.1
℃
0.552 ± 3%
Blank is for reference measurement
2
B Fixed Number
(25/85)
3482.4K ± 2%
3
Fixed Number of
Heat dissipation
2.5mW/
℃
(Min.) (While not boiling)
4
Fixed Number of
Heating
8(15)Sec (Max)(63.2% reaching time
while boiling)
5 Range of Workable
Temperature
-4 ~ 230
F
① ② ③ ④ ⑤ ⑥ ⑦
⑧ ⑨ ⑩ ⑪ ⑫ ⑬ ⑭
Chapter 2 Components description
Chapter 2 Components description
CN7
Description/Part #
HX Temperature Sensor / 7850P-081
Exhaust Temp. Sensor / 7850P070
Water Outlet Sensor / 7850P-019
Water Inlet Sensor / 7850P-015
Check Point
(Main PCB)
CN7
Function
The controller compares each sensor with setting temperature then goes to safety
shutdown when measured temperature is over setting temperature.
Failure Event
Sensor malfunction or overheating condition is detected.
Effects
Improper temperature measurement.
Error Code
Er 16, Er 31, Er 33, Er 35
Diagonostic
① Check temperature sensors wiring connection.
② measure sensor resistance using a multi meter.
Color / Wire Number
① Exhaust temperature sensor (white/blue) : Connector ⑤,⑫
② Water Inlet temperature (blue/blue) : Connector ④,⑪
③ Heat Exchanger Temperature Sensor (white/black) : Connector ②,⑨
④ Water Outlet Temperature (yellow/yellow) : Connector ③,⑩