Potterton Suprima HE 50

Discussion in 'Plumbers' Talk' started by Chris Lewis, Oct 29, 2013.

  1. Chris Lewis

    Chris Lewis New Member

    Hi, first post but have a problem so hope someone can help.

    Recently moved into a new house. Heating system originally had no room thermostat. The wiring was still in place for one, it was just set as if there was a constant call/demand. The previous owner explained that the system did still have something in place to prevent the boiler from just contiuously cycling and that he controlled room temperatures via TRVs on radiators.

    Having queried this, a room thermostat was re-installed.

    Since then, I've had some issues with boiler responding to room thermostat. Thermostat clicks but boiler shows no demand. Eventually,it reacts somtimes after 5 mins sometimes longer.

    Then boiler went off completely, discovered it was a blown fuse,so replaced the fuse. Boiler is now 'working' again.

    However, the problem is that it won't stop working. I had set the heating controls to come on at a certain time and then go off at a certain time. When the time came for it to turn off,it just kept going. The light on the timer clock has gone out, showing the timer is not demanding any action, but the boiler just keeps firing.

    Can anyone provide any advice as to why the boiler would keep thinking there is demand (the demand light on the boiler keeps flashing), when the timer controls are set to off (both heating and hot water are set to off).

    One thing I did notice is that if I cycle through the hot water options on the timer (i.e. on/timed/once/off), the boiler demand switches off when the hot water goes past off, but then it comes back on again after a while.

    Any advice is geatly appreciated.
  2. diymostthings

    diymostthings Well-Known Member

    Hi Chris. From what you describe I think this may point to a PCB fault. Potterton boilers "of a certain age" (including the Suprimas and Pumas) were notorious for poor soldering quality on the PCB. (Surprisingly they were made by Siemens). I have cured two boilers now with "strange" faults by re-flowing the solder over the component legs on the PCB. If you just take a look at the PCB (easy to remove from the side panel) you may see signs of scorching or even a component lead with no or little solder on it. If you are handy with a soldering iron, (and carefull!) it is possible to re-flow the solder over most components but I wouldn't advise the IC's. Worth a look before buying and fitting lots of replacement parts!

  3. Chris Lewis

    Chris Lewis New Member

    Thanks for the advice.

    I'll have a look tonight, and lt youknow what I find.
  4. Rueben Derrick

    Rueben Derrick New Member

    I have the same issue, if its not the PCB could a thermostat cause the same effect?
  5. diymostthings

    diymostthings Well-Known Member

    Well it could be - but in Chris's case if the PCB looks OK (it could still be the PCB) it might be a wiring problem with the programmer/thermostat - especially as there seems to be a hazy history from the previous owner. I should add a disclaimer here that anything you do on a boiler is at your own risk and I won't take any resonsibilty for accidents. Should be checked out be a Gas Safe registered engineer.
  6. diymostthings

    diymostthings Well-Known Member

    Any progress to report?

  7. Chris Lewis

    Chris Lewis New Member

    Diymostthings, thanks for the help and apologies for the delay in responding, but I have been seeing how things went. Having looked at the pcb, and given it a good dusting, everything worked fine..... for a while.

    After a couple of visits from an engineer, the fault has been traced to the integrated timer.

    Only problem now, is that Potterton no longer make that particular timer, so having problems getting our insurance to replace it as they are saying there is no equivalent! Hey ho!

    Thanks again.

Share This Page