Potterton 80e - Hot Water working - CH Not

[Nicolay]

I realise that other people have posted similar issues to this but I guess I have some additional questions.

We have Potterton Puma 80e which is very temperamental. Hot water always works but central heating sometimes cuts out. If we turn the combi to standby for 48 hrs it seems to work OK again for about a week.

When it decides to stop working it fires up and it sounds like pressure builds and after 1-3 mins there is a clicking sound and it cuts out. lats time it happened a bunch of hot water squirted out of a pipe which runs from the back of our boiler through the wall and out on to the patio.

We have had a plumber round to have a look at it - he played with the radiators opened up the boiler and eventually got it going but did not repair anything and could not tell us what the problem was. It has since broken down twice.

The boiler is apparently 11 years old. Is it repairable? and more importantly is it worth it? I've had a couple of quotes for a new boiler - ranging from 2,500 - 4,000. A lot of money but if the potterton is on its last legs anyway I guess it could be worth it. It's too cold to be without heat that's for sure! Any advice on the problem and possible life of potterton combis would be much appreciated. I know nothing about these things so non technical (as much as possible) language would also be appreciated. Thanks, Nicolay

 

[twgas]

when you get thie 'pressure build up' do rads start heating?
if not it could be down to a dripping tap or water leak on hot water supply, try turning off the main water supply to the boiler, turn central heating on and let us know if anything happens

 

[Agile]

Your hot water flow switch is sometimes sticking on from what you are saying.

Totally repairable! I fix quite a few! Not everyone seems to understand how they work!

Tony

 

[ChrisR]

A very mendable boiler. Haven't had to take one out yet!

 

[Nicolay]

Thanks for the advice.

After the boiler was off for 48 hrs this weekend it seems to be going again. However the central heating does cut out when we use the hot water but that might be quite normal.

To answer twgas - the radiators don't start to heat up as there isn't enough time between the boiler starting up and then shutting down for the water to circulate. When I feel the pipes to some of the 1st floor radiators I can feel some heat but it never gets properly going.

The problem of th eboiler shutting down usually occurs after the central heating has been on for a long time i.e. at the weekend.

Good to know its repairable - will certainly save me an arm and a leg. Many thanks.

 

[ChrisR]

I suspect your pump's "gone".
When the boiler misbehaves(cuts out), undo the hex plug from centre and pull slightly - it should want to spin. You might get it turning, temporarily.

 

[Nicolay]

Do I need the boiler to cut out / start misbehaving again before I call an engineer out or would an engineer worth his salt be able to identify the problem even if the hot water and central heating is temporarily misbehaving?

Thanks

 

[Agile]

I always say to the customer wait until it becomes unbearable and there is a very good chance that I will be able to see it misbehave during any 30 min period.

It can be very difficult to identify an intermittent fault.

I remember an intermittent fault which had a pump winding going open circuit when it was well hot after about 40 min on CH.

Tony

 

[Nicolay]

Thanks Tony much appreciated.

I'll wait until it dies again then call.

Nicolay