Central heating problem

BoxerfanUK

I had a similar problem recently and we have separate zones for up and downstairs.

When the heating came on only the upstairs radiators got hot, cold downstairs. Manually moved the slider across on the zone valve and downstairs radiators came on but obviously the downstairs radiators then came on when the boiler fired up for the hot water as the zone valve was now manually open all the time.

I suspected it could be a faulty Synchron motor in the zone valve so bought a new one from Screwfix for £16.00, problem solved. A lot cheaper than calling a plumber out and draining the system down to replace a complete zone valve when just the motor was at fault. This is quite a common problem.

http://www.screwfix.com/p/drayton-synchronous-motor/28670

Annie1960

Le_Kirk wrote: »

They are zone valves, so you probably have separate upstairs and downstairs heating circuits. If they are exactly like that then the bit that has an arrow pointing to it saying "auxiliary end switch" is also a manual override, you open the valve by moving the slider to the right and tucking it behind the little catch above it. What is supposed to happen is that next time power is applied the valve closes. Is your boiler a combi or do you have a hot water storage cylinder?

Boiler is Worcester Bosch, not a combi, i think it's called a 'heat only' boiler.

Rubidium

Annie1960 wrote: »

Boiler is Worcester Bosch, not a combi, i think it's called a 'heat only' boiler.

The first plumber may have diagnosed the problem correctly and the timer/programmer could need replacing - this can easily be proved with a multi-meter.

You would know if you had two zones for your heating as you would likely have two thermostats, one for each zone.

It is more likely that one valve is for hot water and the other for heating.

Your problem is that most plumbers don't do electrics and most sparks don't touch wet stuff.

Risteard

Annie1960 wrote: »

Have looked in airing cupboard. I recognise the pump. There are also two other things with Honeywell on them. Not sure if either one of these is the 3-point diverter valve you mention.

How will I recognise it? I can't see H, M or W.

Presumably it is an S-plan you have rather than Y-plan. I'm not sure why others jumped to the conclusion that it was Y-plan.

Risteard

Rubidium wrote: »

Your problem is that most plumbers don't do electrics

And the ones that do shouldn't. I've never seen good electrical work by a plumber yet. Absolute jokers.

southcoastrgi

Risteard wrote: »

Presumably it is an S-plan you have rather than Y-plan. I'm not sure why others jumped to the conclusion that it was Y-plan.

I'm guessing it's because y plans are far more common maybe

bsod

what model is the timer

is the room thermostat set to call for heat

press the hot water timer on button, and trace which pipes get hot by feel (carefully), then check the position of the lever on the valves.

Risteard

southcoastrgi wrote: »

I'm guessing it's because y plans are far more common maybe

I would say S-plans are far and away more common here to be honest.

Annie1960

Risteard wrote: »

Presumably it is an S-plan you have rather than Y-plan. I'm not sure why others jumped to the conclusion that it was Y-plan.

I have no idea what this means.

FreeBear

Annie1960 wrote: »

I have no idea what this means.

There are different ways of plumbing in a combined central heating and hot water tank. The most common arrangements are fully pumped S plan, Y plan, and gravity systems. For most home owners, the technical details are of little importance as long as the system works and a plumber can fix it.

Google can provide an answer if you really want to know the finer points about each system. But your eyes may glaze over once you start looking.