hi oilman
Sorry to sound thick but what is C and n/c and how do I check the continuity between them?
The cylinder is cold as I haven't had any water heating for about 3 weeks.
Any idea how much a 'strap-on the side of the cylinder' type thermostat costs?
thanks oilhead and Mandate
I replaced the Honeywell 4073 motor valve (apart from the brassware - cos valve in brassware seemed fine). But still no heating or hot-water.
Controller and room-thermo are only just over 2 years old.
I'm thinking maybe it's the HW tank thermostat. I will have...
Hi Mandate
Seems you know what you are talking about, but do you know how hot the synchron motor cover should be - it's almost too hot to touch - is that OK or not?
Hi Mandate and thanks for the informative answer.
Do you know how hot the syncron motor usually gets?
Is the black carbon residue on the inside of the valve cover (described in my initial post) normal, or does it imply overheating?
I'm trying to diagnose why I've got only intermittent central-heating and no hot-water.
I took the cover off the Honeywell 3 way motorised valve and noticed that the cylindrical head of the synchron motor was very hot - almost too hot to touch. There is also a black carbon deposit on the...