hot water no heating

Discussion in 'Plumbers' Talk' started by mrblobby, Feb 22, 2007.

  1. mrblobby

    mrblobby New Member

    Hello, my potterton boiler fires up for hotwater but doesn't fire up for heating. I believe i have a Y-plan system. I have checked the room stat which seems to click on/off properly. Now also the hot water in the taps have become extremely hot, although i am not sure if this is connected with my main problem. any ideas ?? How should i check the 3way valve (acl lifestyle) if this is what is causing it? Grateful for any advice.
  2. boskoman1

    boskoman1 New Member

    i can talk you through it if you have a multi meter???
  3. SGC

    SGC New Member

    Sounds as if your pump is at fault, can you check if its running?
  4. boskoman1

    boskoman1 New Member

    the pump is obviously fine..... it is another external control
  5. I'm betting its the syncron motor in the 3 port valve.
  6. boskoman1

    boskoman1 New Member

    i agree...... but lets make sure.... lets work through it
  7. Mr Blobby... have you a electrical test meter, and know how to use it?

    You'll need to be confident at live testing!

    Have you tried moving the lever on the end of the 3 port valve, to ensure its not siezed up?

    It could be stuck in the hot water only postion, because either the spindle is seized up, or the syncron motor is jammed.
  8. boskoman1

    boskoman1 New Member

    there's no easy solution here..... why not start at the basics.

    i get the vibe that not many people here know the basics of ch wiring
  9. well it is a DIY forum, and agree that electically testing CH wiring is advanced DIY skills, and would involve live testing, which is dangerous, if you dont know what your doing.

    Also the "feel" of a 3 port valve is only gained from experinace.
  10. boskoman1

    boskoman1 New Member

    i bet it is the 3 port. but maybe not.
    I'm here to help people in a logical sequence. I guess you're right that 240v testing should be left to qualified persons
  11. mrblobby

    mrblobby New Member

    I don't have a multimeter,and wouldn't know where to start with one. The pump does run, and the 3-way valve lever moves from mid position to hot water position everytime the water comes on. how can I manually switch it?
  12. Mr Kipling

    Mr Kipling New Member

    Mr Blobby,
    You have confirmed that the three port valve moves under its own steam.

    Set the heating control to hot water and heating.
    Turn the roomstat up high.
    Go to the airing cupboard and confirm that the pump is running.
    Now turn the tank stat down so that the system thinks the hot water is at the correct temp.
    The pump will switch off as the 3 port valve moves to the heating position only.
    If it is working then the pump will fire up again.
    If not, you can remove the cover (beware its live in there) of the 3 port valve and depress the micro switch. If the pump fires up then it means that your room stat is ok and your valve is not moving to the heating side far enough.
    This could be a dodgy motor or a sticky valve. Its like ly to be the latter that has weakened / killed the motor.
    I would advise changing the whole valve unit rather than just the motor.

    I hope this makes sense and helps.

    Cheers Mr Kip
  13. Mr Kipling

    Mr Kipling New Member

    Oh, by the way. If depressing the micro switch does not get the pump fired up then you will need to either get a multi meter as advised earlier and check the system or pay someone to do it for you cos it could be the controller, rooms stat, wiring fault or one of several other things.

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