potterton suprima fault

[ambrosia]

recently I've had 2 customers mention similar faults with their potterton suprimas
both said that the hot water doesnt come on some mornings for some reason and the boiler needs to be reset before it will go back to functioning normally

the problem is it only happens intermittently and neither time was i able to recreate the fault, this obviously makes it hard to fault find.
Both customers were unable to remember the flashing sequence on the boiler, but when asked was it flashing red (ie locked out) thought that it could have been

what i couldnt understand is why is it only happening occasionally, is it an overheat stat, or a PCB problem, where do you start if you cant see the fault

 

[diamondgas]

Prone to intermittent faults in my experience ambrosia ... O/Heat check is best done with hot water only running. Much less water to heat up and more chance of getting it to repeat IMO

Also had one of these shut the pump off when the boiler temp got to overrun temp instead of keeping it running pump overrun mode.

Also had bother with gas valves ... Where do you start? Check the basics, spark gaps etc. if for no other reason than to rule them out 🙂

 

[GrahamM]

In most cases I have found it is the PCB at fault here. They are junk. You may test the thermistor resistance readings to rule that out completely, but if that is OK it is normally PCB.

 

[CES]

Check to see what version of PCB is fitted. If its got the grey knob with the small leds then its probably the old type (see pic). There was a problem with a whole load of these a couple of years back.You can get a harness replacement for approx £200.

 

[dancinplumba]

they were on watchdog, potterton got slated, lots of faulty pcbs but wouldnt accept it was there fault.

 

[ambrosia]

thanks guys

so are those boilers a bit rubbish then, there are an awful lot of them about

my hunch was a PCB i just didnt know how to prove it and rule other possibilities out

do overheat stats normally shut the boiler down till it cools enough to restart, or generally do they just lock the boiler out until its reset
or is it something which varies from boiler brand to boiler brand

 

[gasmarc]

it is usually the PCB that goes on these I have replaced a few over the years and always worried that if I replaced the board and then found that was not the cause I would look pretty stupid , fortunately this has never happened yet on a suprima

 

[quality]

Yes I agree with the chocolate PCB but it is an easy boiler to work on which is just as well

 

[Kev the gas]

Suprima fault finding.

Remove the r/ side panel/ door.

Remove 1 x screw lower the control panel, and observe the brown stain on pcb.

You will see the black stains where the pcb has been smoldering away for years !! I have seen them with soot marks on the flue where the flue passes to the right hand side :winkiss:.

Fair play to the boiler tho as I started replacing the old boards 9 years ago, the new sealed boards came out approx 7 years ago??

 

[gasmarc]

time flys I remember somewhere they say you have to remove the fan in the instructions which is rubbish , I find that sometimes the manufacturers throw in a bit of work that is not required which can be very annoying

 

[heliotrope]

time flys I remember somewhere they say you have to remove the fan in the instructions which is rubbish , I find that sometimes the manufacturers throw in a bit of work that is not required which can be very annoying

On some 100 models the fan has to replaced at the same time as fitting the new board.

 

[snowman]

If its a Suprima that is paired with a boiler mate 2000 then check the circuit board on the Gledhill boiler mate 2000 as these also have intermittent faults on the board that can cause an intermittent duff signal to be sent to the boiler and cause it to lockout or let the boiler think it has satisfied the demand already when it has not, in the second instance it can work like this for months or even years before it fails completely.

Easy fix , but the board is around £225

 

[AmritPedersen]

I've had the same prob with Suprima's over the years. Intermittent prob is usually the pcb, but like gasmarc above I worry about getting it wrong.

 

[gasmarc]

the PCB are around £189 last time I looked and Gledhill charge £1 a minute for their technical department but they are very good