15.0 FAULT FINDING
Fault Finding Solutions Sections A to E
A
Is there 230V at:
1. Main terminals L and N
NO
Check electrical supply
2. Main terminal fuse
YES
Replace fuse
neon
NO
Replace PCB
3. Selector terminals a & b and a & 3. PCB - M1 connector terminals 9 & 10
NO
Check wiring Replace selector
illuminated
B
Is there 230V at: |
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1. |
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Pump |
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| If pump jammed, release | ||
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Replace pump
2. PCB - M1 connector terminals 8 & 15
YES
Change pump supply cable
NO
Replace PCB
C 1.
CH system pressure 0.5 to 1.5 bar
NO
2.
3.
Check the tap of the | NO |
automatic air vent is opened |
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Primary flow valve diaphragm damaged
NO
YES
Open the automatic air vent
Replace diaphragm
Flow valve rod obstructed
D | 1. |
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Continuity across flow |
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| microswitch and PCB M2 |
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| connector terminals 3 & 4 |
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| Primary temperature sensor faulty. | YES | |||||
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| Cold resistance approx. 11K ohms | |||||
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| Fan connections correct at fan. | YES |
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| PCB - M5 connector, is 230V |
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| across terminals 28 & 29 |
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| NO |
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Replace microswitch
Replace sensor
Fan jammed or faulty winding
Replace PCB
YES
Replace fan
Publication No. 5111811 | 43 |