Posting a message to the forum will remove the above advertisement
  1. This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn More.
  2. Checkout our Plumbers Insurance area - heavily discounted Public Liability Insurance and Van Insurance specifically designed for plumbers.

Discuss Potterton Promax HE 15 2004 in the Gas Safe Register Forum - Public Forum area at

  1. Lee Davies

    Lee Davies Member

    OK, so here is an update on this boiler to see if anyone else is the wiser.

    I actually got longer than 15 minutes in the property today.

    I cleaned out the condensation trap, this was blocked, therefore causing the boiler to lockout. The trap was full of 14 years worth of aluminium by the looks of it from the HE.

    Checked the case seals on the CC and they are not passing, therefor I didn't remove the combustion chamber door and it isn't the overheat stat on the fan causing lockout.

    Fan is working correctly, 3 port valve is working correctly, pump is working correctly, electrodes are sparking correctly (I removed them to check spark strength and clean).

    The issue is now as follows.

    Programmer comes on for water or heating, 3 port switches to the correct side, pump is permanently running. boiler acknowledges that there is demand and the fan kicks in. Electrodes spark as they should. Here is where the problem now lies as "sometimes" the boiler will try 5 times and then lockout, sometimes it will fire up first time, sometimes it tries once or twice.

    My gut feeling is the solenoid on the gas valve is being dicky, or the Ignition PCB has an intermitent fault anyone else have any ideas?

    Customer is also asking, due to the age of the boiler and possibility of other future issues, is it more economical to replace the boiler with something like a Viessmann Vitodens 16KW open vent?


    P>S I have submitted my gas safe number to Harvest Fields so I can post in the private section.
    • Like Like x 1
  2. AMGasServices

    AMGasServices GSR

    did you clean the condensate sump?
  3. Lee Davies

    Lee Davies Member

    AMG I did, it was full of the aluminium/carbon from the system, the entire condensate trap is now cleaned.

    Can't be this though anyway surely, as the boiler would not get to ignition if locked out.
  4. CBW1982

    CBW1982 GSR Top Contributor!!

    Have you checked standing and working pressures? Could be water in the line.
  5. king of pipes

    king of pipes Trusted Plumber GSR Top Contributor!!

    Could be repaired but go with your gut feeling the solenoid is easy enough to check , PCB probably around £100 but in all honesty I would be pushing them towards a upgrade , and a service plan which they have neglected by the deposits you have found in the condense trap it wont be aluminium in there as the heat ex is stainless on these. Kop
    • Like Like x 1
  6. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    Test the gas valve eg put meter on inlet and turn the gas off if the manometer drops it’s working but if it starts doing what you say and doesn’t drop gas valve could be at fault

    So test if it’s gettinh the call voltage if not pcb

    But tbh new boiler good choice on a 100w :)
    • Informative Informative x 1
  7. townfanjon

    townfanjon Trusted Plumber GSR Top Contributor!!

    No gas safe badge mate , is it on its way ?
    • Like Like x 1
  8. ShaunCorbs

    ShaunCorbs S. Mod Trusted Plumber GSR Top Contributor!!

    It is
    • Like Like x 1
  9. Lee Davies

    Lee Davies Member

    If you mean my GSR badge I have given my details to admin via pm WEEKS ago, I sent it to Harvest Fields today so hopefully he can help out.

    Can't believe I didn't think of that earlier.
    Thanks again.
    • Like Like x 1
  10. townfanjon

    townfanjon Trusted Plumber GSR Top Contributor!!

    No problem pal , hes a bit slow sometimes lol

    Here comes the abuse
    • Funny Funny x 3
  11. Harvest Fields

    Harvest Fields S. Mod Trusted Plumber GSR Top Contributor!!

    It’s being sorted mate. He has sent me his details. But I have been a bit busy. I’ll pull my socks up and crack on now though.:p:p
    • Funny Funny x 2
    • Friendly Friendly x 1
  12. Harvest Fields

    Harvest Fields S. Mod Trusted Plumber GSR Top Contributor!!

    No abuse mate.:p:pcannot argue with the truth:D:D
    • Funny Funny x 2
  13. AMGasServices

    AMGasServices GSR

    Is the sump clean too?

    Yes it can the condensate water will build up. Causing it to lock out.
    • Like Like x 1
  14. Lee Davies

    Lee Davies Member

    Ok all, an update on this friggin Potterton.

    I couldn't rest as it's getting on my nerves not being successfully in fault finding this boiler.

    I went back to to tenants house (obviously I won't be charging for this) and could not replicate the issue.

    The boiler was on when I arrived and the tenant said it came on without him having to flip the reset. I turned it off and on numerous times but it lit without fail each time.

    I check the lines for water anyway and all is good.
    Nothing stands out now
    I am now decided that the gas valve is not the issue.

    Maybe an intermittent ignition PCB fault which ran alongside the blocked condensate?
    • Like Like x 1
  15. king of pipes

    king of pipes Trusted Plumber GSR Top Contributor!!

    Rectification fault maybe ? I have had this on a slightly squashed ignition lead resulting in a weak spark and failing to ignite the gas pilot causing nuisance lockouts, worth checking . Kop
    • Like Like x 1
Similar Threads - Potterton Promax 2004 Forum Date
Potterton Promax leaking Gas Safe Registered Plumbers Only Feb 13, 2019
Potterton performa 28 combi Gas Safe Registered Plumbers Only Mar 17, 2019