Potterton Statesman oil fired boiler - lock out

[19499787]

I've just moved into a house with a Potterton Statesman C/H boiler.

The boiler is set for automatic sessions (1 hour in the morning, 2-3 hours in the evening), its theromstatic controlled so the boiler cuts in and out when the radiators get warm.

Problem is it 'locks out' after the first fireing of a session, then needs manual resetting. Main issue if the boiler is still warm it just won't reset, it tries, there are electrical whirring sounds, no fan at first, then locks out again.

Had the local engineer round (corgi rated) several times, everytime he says he can see nothing wrong, just pushes the button and it starts again.

I've read several entries on here, folk understand these things better than I do, any tips on where to start would be useful, even knowing what qualifications in a heating engineer I should be looking for.

Our last place had a ESSE cooker/heating system, best thing we every used, was pleased when the new place had oil. Lived here 5 weeks, felt cold all the time.

thanks for all help

D

 

[Agile]

I've just moved into a house with a Potterton Statesman C/H boiler.

Had the local engineer round (corgi rated) several times, everytime he says he can see nothing wrong, just pushes the button and it starts again.

To work on an oil boiler its better to someone registered with OFTEC although thats not a legal requirement yet.

The question is more of what experience he has of your boiler. You dont expect to "see" whats wrong. Diagnosing faults requires testing!

Your problem seems to be one of overheating at the end of a heating session. I immediately think of a failed pump over run!

Its not possible to give an immediate web answer as tests need to be made:-

Is there a pump over run?

What temp is the boiler reaching?

What temp is the o/h stat tripping at?

Tony

 

[oilman]

It could be your oil, oil pump, motor capacitor, leaking flue, electrodes or motor in roughly that order. It might be something else too.

 

[doitall]

It could be your oil, oil pump, motor capacitor, leaking flue, electrodes or motor in roughly that order. It might be something else too.

I think its the other bit thats locking out oilman.

Faulty overheat stat or circulation problems e.g. pump sticking.

There are a few other possible causes but would depend on age of the boiler.

 

[oilman]

It depends what's meant by "locking out". I had assumed it was a burner problem, in which case the overheat stat would not have an effect, and since it locks out on the first firing of a session.......

We need some more information from 19499787.

 

[19499787]

Thanks all so far, wow, was surprised at the response.

Age of the boiler is 3-4 years.

My defination of Locking Out.

The boiler automaticaly fires and runs (like first thing in the morning), the rads and water reach the required tempreture. The thermostat shuts the boiler down, when the water/rad tempreture drops the 'boiler' should startup again, there are various whirring noises and a click, the orange 'lock-out' light on the front comes on and nothing happens.

My steps are to take off the front cover and depress the plastic 'reset button'

There is a warning near the plastic reset button 'This should only be reset twice'

When the reset button is depressed the boiler attempts to start, invariably it doen't.

I normally press the reset once or twice, turn off the boiler at the wall switch, leave for an hour or so and try again.

From the wall switch, the boiler either starts at first press, or whirls and clicks and goes into reset mode.

My main question here is what I should be looking for to tell the heating engineer when I next call him, what should I be asking him/ what should I be telling him.

My interest was watching a recording of the watchdog program about Potterton Gas boilers, symptoms expalined on there were exactly the same as I'm getting.

D

 

[cjb1971]

You checked the oil filter??ive ben to a few which lock out after while then wont re-start for a certain period,faults on a couple of these were the fact that the inline oil filter was clogged up.

 

[cozzmic]

Could probably do with a service. When was it done last. The PCB (watchdog) prob applies to the Suprima (gas) boiler. Think I've only replaced a pcb on an oil boiler once in twenty odd years. Filter as said first place to look and that you have sufficient oil in the tank. What type of oil do you have Kero or Deisel.

 

[doitall]

I still think its the overheat stat thats cutting out and not the burner

Can the OP confirm where the button is, on the front of the burner or the facia panel.

 

[cozzmic]

The one that says reset only twice is usually on the control box on the burner.

 

[doitall]

The one that says reset only twice is usually on the control box on the burner.

If that is the case then it could be a combustion problem on that model.

Or a flue blockage

 

[baxpoti]

19499787

Are you pressing an orange button with an X on it, that clicks when you push it or a lit up red button, if it's the latter

I'd guess the oil pump drive coupling is worn

24940496

 

[oilman]

Just tell the service guy it locks out. Don't bother with any other information as it might lead him up the garden path. If you give him an idea it might be something, it'll just cost time.

Definitely no connection with Watchdog program.

 

[Agile]

But do tell us what it was.

We still dont know if its a temperature overheat or a combustion problem.

I would still think it might be a temperature o/h because it runs OK for the first firing until it reaches stat temperature.

But it still could be either!

Tony

 

[19499787]

So many questions, but thanks.

The button is behind the facia pannel on a grey box about 1ft cubed, about 8" above ground level, its made of plastiised rubber molding, when depressed it responds with a orange light

Reason for posting here origianlly was the local 'specilist' has been out around 4 maybe 5 times, in the past 4 months, everytime he comes presses the reset button and the thing starts, we sit around and drink tea for an hour or so and it doesn't cut out, was fishing for clues on what it could be.

Think he is just as frustrated as his fee base (currently) no fix no fee, which I feel quite guilty about, I'd like to 'tactfully' suggest we ask for a second opinion (that was the purpose of posting here, trying to get some background), which I must admit has given me lots of notes.

Certainly look at cleaning the in-line filter, although don't beleive a registered heating engineer would miss a trick like that, also verifying the sg of the fuel.

(according to the paperwork the boiler has been fitted with a conversion unit allowing heating oil instead of Kero to be used

The boiler has been serviced at the intervals specified by the installation engineers (normally every 8-9 months), last time.

My thoughts were along the lines of a airlock (the tank is about 30% full). I've ordered a load for this week which could push through the airlock if I carefully crack one of the joints/ clean out the filter. But again I cannot beleive the engineer would not have thought of that solution.

Actually like the suggestion of the Thermostat, possibly siezing.

Will keep all informed,


Thanks for some excellent posts and advice.

D