Potterton Netaheat Electronic 16-22

[pixey]

Hi again.
I have a Netaheat 16-22 which has just began playing up.
When you start it up, the fan comes on, then the pilot lights after a few seconds, then the main burner lights. It stays lit only for about 7-10 seconds before the main burner slowly "dies", and then the whole sequence starts again.
I have read that these can be quite dangerous boilers and am aware that I should not remove the main case, but would appreciate any help.

Paul

 

[ChrisR]

See if the aps is dropping out. Connections are on the pcb outside the airtight box.

 

[pixey]

Thanks Chris. I pulled one of the clear tubes / pipes that connect to the air pressure switch, turned the boiler on, but only the fan came on, no pilot light or anything else. I re-connected the pipe to the aps while the fan was still running, and pilot lit straight away, and then main burner and then it all died again, as before.
Is there any other test to do an the aps or does this mean it is working ok?

Paul

 

[ChrisR]

No that doesn't test anything.
Obviously the aps was seeing the fan come on in the first place otherwise the burner wouldn't have lit. Question is whether it goes off again - needs someone competent with the circuit and a meter to see.

If not that then I would check pilot and flame detection. Not a nice job. Bits of asbestos and rusty metal make bids for freedom. Have to use tecky kit to test the seals to stop customer getting CO poisoned before he pays the bill.
Don't you go taking the case off - corgis with experience only.

 

[pixey]

Hi Chris.
I had the pcb and the pilot electrode changed about a year ago with a different fault so hopefully it is not those.
I am pretty confident on the electrical side so if you could tell me what I am looking for with regard to testing the aps I would appreciate it.

Paul

 

[pixey]

Well thinking about the problem being with the fan aps blocked flue or something along those lines, I thought I would visably check the flue, as it has been very windy here lately. When I looked outside I could see that some light aluminium ladders that have been chained up to a soil pipe had shifted with the wind and was partially in front of the flue exit.
I moved the ladders and tried the boiler and it now seems to be working fine.

Just shows that you should always check the simple / obvious things first.

Thanks for your help Chris.

Paul

 

[Agile]

Thats why I always train people to check the flue first BEFORE they start to try fault finding!

Isn't that a clever boiler that can protect itself against an idiot with a ladder?

Tony

 

[pixey]

Thats why I always train people to check the flue first BEFORE they start to try fault finding!

Isn't that a clever boiler that can protect itself against an idiot with a ladder?

Tony

Agile, I think your comment is a bit stupid. No one on this forum suggested checking the flue first and as for the idiot with the ladder, it has been chained up unused for at least 6 months, so I find you comment provocatave and a complete waste of time.
I only informed the forum of the outcome so as to make other people aware of such a simple problem.

pixey

 

[Trance Nation]

Thats why I always train people to check the flue first BEFORE they start to try fault finding!

Isn't that a clever boiler that can protect itself against an idiot with a ladder?

Tony

Agile, I think your comment is a bit stupid. No one on this forum suggested checking the flue first and as for the idiot with the ladder, it has been chained up unused for at least 6 months, so I find you comment provocatave and a complete waste of time.
I only informed the forum of the outcome so as to make other people aware of such a simple problem.

pixey

Although in fairness Agile's point is spot on, just put across harshly !

 

[ChrisR]

Thanks for coming back pixey. It hadn't occurred to me in your case, but we see plenty of boilers messing about when ivy decides to get into the flue. Though it's probably only 1% of airflow problems, and they usually fail to light reliably in the first place.
All faults are obvious when you know what they are. I don't remember any other posts where Agile has suggested checking the flue first.....

Oh and if the Netaheat were a slightly clever boiler it wouldn't light with the cover off, which it does.