EHC Fusion, Installation & Technical Manual

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13
GB-016C_f.493
FAULT FINDING
boiler key
1. Control Panel
2. Over Heat Stat
3. Automatic Air Vent
4. Heating Elements
5. Copper Heat Exchanger
6. Printed Circuit Board
7. Voltage Free Control Connections
8. Circulation Pump
9. Flow & Return Sensors
10. Flow Switch
11. Pressure Guage
12. Expansion Vessel
13. Heating Flow
14. Heating Return
15. Pressure Relieve Valve
16. White Metal Enclosure
1
3
4
5
6
9
7
8
11
13
14
16
15
12
10
2
Symptom Reason Procedure
The indicators on the front panel
are off
No power to the boiler Check electricity mains power supply
Main over heat stat cut-out
Check the power board fuse F2
Check the WT3 temperature safety cut-out investige cause - possibly
fault / return sensors
The „B” indicator is flickering
Flow sensor is blocked
Check flow sensor
The central heating system airlock - vent the central heating system
and the pump
Check for choked pipes
Circulating pump is blocked Move the pump rotor manually
Flow sensor failure Check the flow sensor and replace if neccesary.
The room thermostat indicates
that the boiler is switched on.
„C” indicator does not light
Control panel fuse failure
Find the failure reason then replace the fuse.
Check external controls, room stats, etc. are calling for heat.
Link out control stats connections to eliminate external controls
If boiler operates the fault is with the external controls
The „D” or „E” indicator are
blinking
Temperature sensor failure Replace temperature sensor.