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  1. ptg1174

    ptg1174 New Member

    hi guys

    a few weeks ago my hot water started getting really warm after some googling and speaking to a plumber came up with cylinder stat, i ordered and replaced but still the same, what i have noticed is that when my gas central heating is on it also heats the hot water i know this as I've not switched hot water on but still get loads of really hot water, I've also changed room stat thinking it was this there is 2 drayton zone valves that i have replaced within the last couple years,as my system is about 15 yrs old any help would be appreciated before i call in the professionals to see if its something i could replace myself

  2. king of pipes

    king of pipes Trusted Plumber GSR Top Contributor!!

    Get a electrician to check the controls you could try setting different times on your programmer for hot water and heating to prove the programmer is not the cause .
  3. quality

    quality Plumber GSR

    Sounds like you need to get a good heating engineer in to identify the problem or you could of wired the cylinder stat wrong
    Last edited: Mar 17, 2017
  4. ptg1174

    ptg1174 New Member

    thanks for the reply the programme for hot water is not timed to come on i switched it off its only the heating thats on programme
  5. ptg1174

    ptg1174 New Member

    thanks for reply the cylinder stat only had 3 connections i will probably have to get somone in
  6. rpm

    rpm Trusted Plumber

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  7. steadyon

    steadyon Active Member

    I'd suspect the hot water motorised valve, even if its only two years old. Take the head off the valve, and manually turn the valve off. Turn central heating on and see if pipes to cylinder coil get hot. If not, that's your problem.
  8. king of pipes

    king of pipes Trusted Plumber GSR Top Contributor!!

    I think you need a electrician mate something not right there , if you have 2 seperate zone valves you have a s plan you should have time and tempreture control for each via a twin channel programmer a room stat for the heating , and a cylinder stat for the hot water , unless its controlled on a single channel timer and you relying on the cylinder stat for water temp and time control for heating via the timer and no room stat outdated way of doing it is that what your saying post a picture that would help .
    Last edited: Mar 17, 2017
  9. DAVE01

    DAVE01 New Member

    Hello Would not be going mad changing anything if its a 2 zone heating system 1 MIV is controlled by a room stat for heating only 2 MIV is controlled by Cylinder Stat all are controlled by a Dual Programmer One side for hot water one side for heating
  10. DAVE01

    DAVE01 New Member

    Hello would not go mad changing anything just check both stats are opening and closing the Zone valves but in order for all to work you need a Dual Programmer one side for Heating and the other Side for Hot water Go on your Phone and check Drayton they have a drawing on how system should be wired they even give you the colour code of the different wires and were they should go Just make sure you have a Permanent live to boiler this is for Pump Over Run and a 3 AMP Fuse in Spur Switch at Boiler The Only way to use a system like I think you have is to have two pipes going to Hot Press or linen Press this way you can have Hot water or Heating Only And I would not be at all surprised if short cuts have been taken Regards Dave 01 Heating Engineer with 40 years Experience
  11. jtsplumbing

    jtsplumbing Plumber GSR Top Contributor!!

    Seems to be a mix up with the wiring or a faulty programmer, valve for hot water is staying open when heating is on (or letting by) when you replaced the 2 port valves did you replace the complete valve or just the power head ??
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