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Discuss Boiler Connection Help in the Central Heating Systems area at ElectriciansForums.net

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Can anyone help, I have just done a rewire on a house that has been completley refurbished and the homeowner has decided to put the old boiler (Glow worm) back into service and wants a s plan. I dont normally get involved with boilers and there is no wiring diagram for the boiler. There is 2 flex cables coming from the boiler, one has the usual Cpc, Live and neutral. the other is a 5 core flex and without the wiring diagram that came with the boiler, i need to know what each core serves



Not 100% certain but i would think the 3-core goes out to pump (over-run), and i would say your 5-core serves a permanent live, neutral, cpc, and switch wire. I've a feeling you may have a spare core??



Hi TJS, If you supply us with the following:
Make, model and serial number of the boiler.
Make and model of the heating controller/programmer, pump, valve(s) and thermostat(s).
We can then give you specific circuit and connection details.
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There is no other way to determine what each of the cores (including cpc) connect to, apart from you personally finding out.
Personally, I would disconnect whatever is there, test the integrity of both cables, and start from scratch.
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