Alpha CB28 No hot water

Discussion in 'Plumbing and Central Heating' started by lisa31, 10 Oct 2011.

  1. lisa31

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    Hi,
    Have posted on here before and got great advice and help so am back again for more....CB28 had a new diaphram few months back and all was good then all of a sudden im not getting hot water, sometimes it works...and sometimes it point blank refuses and both the red and yellow neon lights flash alternatly, i can sometimes get it going again by reseting it.
    I am thinking it may be the DHW switch thingy.....if it is...and me being a woman...would i be able to replace it myself or do i have to phone the uncle who fixes boilers but also drives me scatty ( think the chuckle brothers )

    Any help would be appreciated...thank you :)
     
  2. Rob

    Rob

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    Red and yellow alternating would indicate faulty pressure switch.
     
  3. jasongates

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    Or that your system pressure is too low, what is your pressure gauge showing?
     
  4. heatech2301

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    hi read your problem its the microswitch just requires the thin metal plate bending a little this should cure your problem and yes providing you isolate the power to the boiler it should cure if in doubt get a pro in hope this helps ....
     
  5. nickso

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    er......no. :LOL:
     
  6. lisa31

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    System pressure is fine, i think, 1.5 when cold ( in the green bit on the dial ) and rises to 2 when the heating is on ? all radiators have been bled and all get hot when the heating is on.

    I dont mind having a go at things myself if i know im not going to blow up ha
     
  7. compheat

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    A and B flashing (both red) alternately idictate a pressure problem.
    I didn't realise that both the red and yellow lights flashed.

    A=Red
    B=Red both fault lights
    C= burner lit
    D= power on
     
  8. Agile

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    I did not remember this boiler has a pressure sensor.

    Lisa, regardless of the dial pressure, increase it a little as the indication seems to indicate the electronics thinks its too low.

    Tony
     
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  9. DP

    DP

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    If indeed the plunger fails to operate the switch, then there would be a reason for that not happening. BENDING the lever is NO cure. Poster, will you take the responsibilty of dealing with the boiler if burner fires up and melts the combustion chamber because there is no water in the system but the lever has been BENT to initiate ignition sequence? I think not- act responsibly.
     
  10. Rob

    Rob

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    The Cb28 only has two LEDs ;)
     
  11. Agile

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    But a single LED can be bi or tri colour.

    By varying the power to each individual colour a wide range of colours can be produced. As used on LED television displays.
     
  12. lisa31

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    I increased the pressure and it still cut out, and it does only have 2 LED lights and have only ever seen red and yellow, never any other colour, the manual also says it only has red/yellow neon lights. I think i would prefer to buy a new part rather than bend or mess with the one that is already there as im not ready to die yet ha ha.
     
  13. DP

    DP

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    Not on this boiler Tony.
     

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