Potterton Suprima 80 - strange stuff happening

[Scuba303]

Hi there,

This is my first posting - apologies if a similar problem to this has been posted but I've had a good look and couldn't find one. It seems to have confused 2 different engineers too ......

I am at my wit's end with our Boiler - Potterton Suprima 80 L - Honeywell Timer.

About 3 weeks ago, it woke us up by making a loud vibrating and whirring noise - (not banging). The timer controlling the HW/CH was off and when I pressed "over-ride" to see if it would stop the noise, it had no effect. The noise lasted about 10 seconds, then went off for 25 seconds, back on for 10 seconds and so on. This continued all night until the HW/CH came on in the morning. Noise stopped for a while, then intermittently returned and has been driving us demented (esp at night) ever since.


First engineer said he'd never come accross such a thing - but advised I have the PCB and Fan changed even though he couldn't find a fault with them?! I declined. Tried Potterton and guy admitted he didn't know what it was but changed the PCB as part of the 1 year payment contract I'd just taken out. There was a tiny amount of slight scorching on the PCB. He said the fan was absolutely fine.


Since the first night when the noise was unbearable, it has quietened down a bit but is still doing the same thing. Not all day and night but intermittently. Sometimes it won't do it for several hours. Noise is like the boiler is powering up but WITHOUT the ignition click if that makes sense - then with intermittent on and off as above. It doesn't make the timer come on and doesn't appear to interfere with anything if timer is on.

I'm confused as to what can make it activate with these strange noises when it's off according to the timer. What else could be making it do this?

Any thought would be really appreciated - have had 3 weeks of broken sleep - same Potterton engineer due tomorrow but am worried he still won't know what it is.

It is wallhanging to a party wall with house next door (housed on first floor within cabinet) and suspect it's driving the neighbours mad too

Thanks to anyone who may be able to help.

Hazel

 

[gas4you]

If it is on a fully pumped system, then a faulty 2 port or 3 port valve can try to turn the boiler on even if the timer is off, although if it has been wired correctly this should also make the boiler fire up as well.

I assume that the 2 engineers you have had round have checked any/all external controls and zone valves?

Have you an external frost stat fitted and no bypass fitted to the system?

As the pcb has been changed I would assume for now that it is not this at fault.

 

[Scuba303]

Dave,

Thanks for v quick reply. Engineers looked briefly at valve but not sure how thoroughly they checked. I can mention that tomorrow.

Don't know if I have frost stat - no bypass(?) fitted - will ask engineer to check. We moved in 2 years ago and house was totally renovated 5 years ago so e/thing is pretty new and up to date.

Had no probs with boiler, etc., at all until 3 weeks ago. If wiring was done incorrectly, would prob not have started before now? Can valves just become faulty like any component or are they driven by something else?

Sorry to sound useless but am jewellery designer - this is new territory to me.

Thanks again,
Hazel

 

[Agile]

If you set your location more closely than just UK that might give us a clue.

So would saying where the boiler was fitted.

Tony

 

[Scuba303]

Hi Tony,

Am in Ealing, West London. In first posting, I did say where boiler was fitted - in a first floor bathroom in specially designed shelf cabinet - back of it is on party wall to next door - the side is by external wall and vent leads directly out. Hope that helps?

Thanks .....

 

[Agile]

Although five miles away its only 0.3° outside, I think we can discount a frost stat being activated as none would normally be fitted in London with an indoor boiler.

There is no obvious cause for the problem although a faulty motor valve switch is a possibility but that would cause the boiler to fire up and run to the normal operating temperature.

Its a feature of the design of your model that the o/h stat will trip if the boiler thermostat is turned up too high.

I recommend they are set between 2.5 and 3.5 !

Tony

 

[Scuba303]

Thanks Tony - I will mention these things to Engineer No. 3 tomorrow - really appreciate you taking the time.

 

[gas4you]

Although five miles away its only 0.3°

As most frost stats are set around 3C I would expect one to have kicked in at this temperature, but then the boiler be held off from firing by the pipe stat on the return, until the water temp dropped also.

 

[Scuba303]

Engineer arrived today and boiler happened to do what it's been doing while he was here. Investigations showed it was a faulty valve on the 3 way valve system. He repaired it and all is silent - keeping my fingers crossed it stays that way.

Thanks for all your good advice guys - it was very much appreciated and showed you were barking up a closer tree than the engineers.

Hazel

 

[Agile]

Engineer arrived today and boiler happened to do what it's been doing while he was here. Investigations showed it was a faulty valve on the 3 way valve system. He repaired it and all is silent - keeping my fingers crossed it stays that way.
Hazel

Did you have to tell him that we suspected the three way valve?

Tony

 

[Scuba303]

I mentioned it but it was a different engineer and he was much more clued up than the others. He agreed the forum is very helpful.

 

[Agile]

I mentioned it but it was a different engineer and he was much more clued up than the others. He agreed the forum is very helpful.

Do you mean that he actually looks at this forum?

Tony

 

[Scuba303]

Don't think he does.

Just interesting that you had suggested what it actually turned out to be and how useful information sharing can be.

Thanks again.