Hot water and rads comming on

Postby Sixty Six » Tue Aug 05, 2008 7:32 pm

Hi, my heating comes on when I only want hot water. I have tried to select hot water only on the control but the rads still get hot. I have thermo valves on the rads and I have switched all of them off except for 1 so the water can flow round the system ( not sure if this is right or not).

Is there any thing I can do as I cannot afford to get a pro in at the moment.

Thanks 66
Sixty Six
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Simply Build It

Postby AdamsHeating » Wed Aug 13, 2008 1:30 pm

Is it a combi boiler system or tank and cylinder system?

If it's a cylinder with tanks in the loft, it sounds like your three port valve may be broken. It's an easy job but a wet one if done incorrectly, and there will be a bit of wiring into the junction box.

Parts won't be too expensive but you will need a few spanners.

Let me know how you get on.

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Postby TOPSPARK » Wed Aug 13, 2008 3:22 pm

It sounds to me as you have a problem with your time clock and the connections are crossed but as without a better description of set up would hate to comment any further
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Postby sparx » Wed Aug 13, 2008 6:13 pm

hi, you don't say anything about the system but if it was working before then a fault has developed which could be motorised valve stuck, or a room thermostat contacts stuck(if one is fitted) or the programmer has gone faulty (unlikely).
how many motorised valves are there? one with 3 pipes to it,
or 2 with 2 pipes to each?
whichever you are going to need help so ask around for local trusted control engineer who may be known as an electrician or a heating engineer or a plumber, there are some good and less able of each type, because even if we narrow down the fault on here most fixes are not going to be DIY, sorry,
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Postby Sixty Six » Wed Aug 13, 2008 7:46 pm

Adamsheating, Topspark and sparx,

thanks all for you input. The system is a boiler with a water tank in the loft, I also posted another thread asking the same question ( a bit new to all of this ) and also looked at all of this site for answers. I have now replaced the actuator - 3 port valve - and all is well.

Again, thanks for the response it is appreciated.

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