Heating keeps coming when boiler is switched on

yellowfish · 19 Sep 2005

Hi,

Model - Biasi 24s GC - 74 970 06

Been working fine, all of a sudden the central heating comes on automatically. A friend said it's likely the divertor Value. Should I get this replaced or just the Membranes in the Value?

Thanks for your help!

kevplumb · 19 Sep 2005

all of a sudden the central heating comes on automatically

when you run the water or at random

Agile · 19 Sep 2005

The system water is dirty and has caused the right hand diverter valve gland to leak water into the DHW flow switch.

The water needs to be flushed out and then the gland and switch have to be changed. The operating pin has to be replaced or properly cleaned otherwise the problem will reoccur.

As the gas valve has to be removed to gain access, this is a job for a CORGI engineeer.

Tony Glazier

yellowfish · 19 Sep 2005

As I switch on the boiler it starts the heating, once the heating gets hot it stops. (assume it cuts off once it reaches a certain temp??)

Thanks for all your help!

kevplumb · 19 Sep 2005

does not mention having to remove the gas valve here

Agile · 19 Sep 2005

Thats quite true Kev and its because the manual is only describing removing the switch. You can just about do that in situ using forceps to take off the clip if you have patience and an inspection mirror.

To remove the gland the gas valve has to be removed.

In practice when the gland has been leaking the clip for the switch is usually so rusted it cannot be taken off anyway.

The manuals seem to assume the system was power flushed and the gland will never leak. The real world is different!

Tony Glazier

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Heating keeps coming when boiler is switched on

yellowfish

kevplumb

Agile

yellowfish

kevplumb

Agile

DIYnot Local

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