Hi all,
I have a standard y-plan gas heating/hot water system. The hot water works fine, but for the last six months or so whenever I switch on the central heating it works for around ten seconds and then cuts out, with quite a loud "clunk" seemingly eminating from the Honeywell V4073a mid-position valve. After another ten seconds or so, the boiler reignites and the same thing happens again, and so on...
I've discovered that if I slide the slider on the Honeywell valve to the "Open" position, then the heating works OK. But I noticed on the pdf data sheet for the valve
So my questions are these:
- What is most likely to be causing the problem?
- Is it safe/sensible to leave the valve in the Open position until this is fixed?
I'd be hugely grateful for any help.
Duncan Clark