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Andrew Smith
Andrew Smith, Home Appliance Technician
Category: Appliance
Satisfied Customers: 3768
Experience:  Gas cooker specialist
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CH control HoneywellST9400C. Programmed as last winter. Not

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CH control HoneywellST9400C. Programmed as last winter. Not touched. Water comes on as timed. CH lights but does not come on. Wall thermostat "clicks" as 60 degrees but changing temperature position has no affect Any ideas?
***** ***** : Are you able to check the motorised valve in the airing cupboard?

what does it look like and where on boiler

***** ***** : No, in the airing cupboard
***** ***** : A silver or white box near the pump?

I think, yers. Its nexct door. give me sixty secs


pensil box white sized Honey well box, sealed by pump (new)


found also silver box with slide lever at top end. Any good?

***** ***** : Yes, when on heating then the slide lever should opena dn
***** ***** : and fire the boiler
***** ***** : Can you put it on heating only and tell me what the box deos?
***** ***** : *does

water off. slid lever to other side. it slid back slowly in a stiff but apparently controlled way


as yet boiler not fired

***** ***** : with the heating on?

heating light on automatic in control. boiler not fired. try again?

***** ***** : No


***** ***** : You need a new head for your motorised valve
***** ***** : The motor should open the valve to put the heating on
***** ***** : If you push the lever and latch it open
***** ***** : Then at least you will get heating while the hot wtare is on

have ot touched it but wife calls that boiler has just fired. I switched off water.

***** ***** : It may have been stuck, but you will know for sure if you put the heating only on

seems fingers crossed and if fails then new head on Mon. Mm?

***** ***** : Yes, good call.
***** ***** : But if you lose the heat again then open the valve and latch it and you will have heat when the hot water is on

OK. Thanks a lot. Iver learned somethingh as well!

***** ***** : ;-)

the bairns will nae freeze ;-)

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