Central Heating Question

Re: central heating question

I have a Megaflow system with potterton profile boiler and a new Honeywell 9400 programmer.Up to now it was working fine .After draining the system to add fresh inhibitor , the central heating now only works when I turn on the hot water switch.The system was plumbed with separate motorised valve for hot water and separate for central heating,If I switch on the central heating switch the central heating does not work but if I switch on hot water switch the central heating and the hot water works. Also the new central thermostat does not work as even if I turn it to zero the central heating system works as though its on maximum temperature from hot water switch only. The system remains completely off if I switch on the central heating switch from the programmer Any idea of what to do ,any advice will be highly appreciated.

2 Answers

Sounds like the heating zone valve is jammed so not making the auxiliary switch. This would also explain why the heating is so hot.
It may be possible to free it. If not, it may need to be replaced.

Answered 8th Feb 2013


Member since 3 Nov 2010

Hello, if any of the valves were stuck it would not make any difference what was switched on. The wiring is wrong or you have the wrong programmer

Answered 10th Feb 2013

chris tomlin

Member since 28 Mar 2012

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