Potterton Housewarmer 55 step flow not working properly

[Philip Payne]

Hi can someone help resolve issue with burner fire up on my Potterton Housewarmer 55?

The burner seems to start mostly on full gas, the lower flow at startup seems to be failing most of the time.
This means that the boiler igniting is quite noisy, on the odd occasion that the step flow seems to work the boiler fires up reasonably quietly.
The PCB was replaced recently due to the pilot ignition not working at all, at which time the oxypilot and electrode lead were replaced, now the pilot works nicely but the burner startup has not changed. This noisy startup has been present for sometime on the boiler, it's not a great annoyance, however it would be nice to clear that issue as well.
The step flow is controlled by what the gas valve or the PCB? How is the lower gas flow at initial startup done, is it something in the gas valve that is failing to operate or is it a fault on the electrics controlling the valve.

Your help would be greatly appreciated.

Thanks

Phil.

 

[AGAS]

Hi can someone help resolve issue with burner fire up on my Potterton Housewarmer 55?

The burner seems to start mostly on full gas, the lower flow at startup seems to be failing most of the time.
This means that the boiler igniting is quite noisy, on the odd occasion that the step flow seems to work the boiler fires up reasonably quietly.
The PCB was replaced recently due to the pilot ignition not working at all, at which time the oxypilot and electrode lead were replaced, now the pilot works nicely but the burner startup has not changed. This noisy startup has been present for sometime on the boiler, it's not a great annoyance, however it would be nice to clear that issue as well.
The step flow is controlled by what the gas valve or the PCB? How is the lower gas flow at initial startup done, is it something in the gas valve that is failing to operate or is it a fault on the electrics controlling the valve.

you might as well change the gas valve after changing the PCB , electrodes and oxy assembly , really !!!

 

[petit_pablo]

Get a competant RGI out. The main burner is backlighting at the injector. Its a common fault on housewarmers .

 

[Philip Payne]

Hi AGAS, thanks for your reply, it's not a matter of the cost, if the step flow is not controlled by the gas valve why change it? The reason why the oxy pilot and electrode were changed was due to intermittent sparking issues, that didn't help and eventually the sparking failed altogether and thus the PCB was changed which was the real cause as the ignition of the pilot is now spot on.
It seems that people want to change components indescriminently in order to try and resolve a fault without trying to understand what is causing it and thus work out the resolution logically.

Phil

 

[Philip Payne]

Hi petit_pablo, thanks for your reply, can you please explain what you mean by "The main burner is backlighting at the injector" ?

The burner was removed and cleaned has something been missed? why would this affect the step flow gas release?

Regards

Phil

 

[Agile]

The forum rules forbid us giving DIY gas repair advice here.

The obvious advice would be to get a competent gas reg. engineer to diagnose the problem.

Tony

 

[Philip Payne]

Thanks Agile, however finding an engineer from a telephone book, who will understand how the step flow works will be nigh impossible.

As it seems here, this is not something that is widely known.

Gas engineers seem to replace items based on a best guess which seems a costly and not best practice for the customer scenario.

There must be someone on this forum who has an understanding of how step flow works?

I'm not asking for specific instructions just a pointer as to the cause.

regards.

Phil.

 

[Agile]

It seems pretty simple to me!

But as I have explained we are not permitted to give DIY gas repair advice here!

If you are worried by the cost then you can get a fixed price repair from Potterton/Baxi for about £300.

But of course a DIYer will not want to spend any money at all.

You should not have to pay for parts which are not required to fix a fault.

But that does not help DIYers as they cannot get refunds on parts they have fitted to "see" if that was the fault!

Tony

 

[bernardgreen]

But that does not help DIYers as they cannot get refunds on parts they have fitted to "see" if that was the fault!

Nor can they get refunds on parts fitted un-necessarily by "qualified" but incompetent people trading as service engineers.

 

[Agile]

Nor can they get refunds on parts fitted un-necessarily by "qualified" but incompetent people trading as service engineers.

Why would anyone employ an incompetent engineer?

Even if they did have an unnecessary part fitted its unlikely they would want to pay for it.

That's the advantage of employing a professional.

Tony

 

[bernardgreen]

Why would anyone employ an incompetent engineer?

Because until they have "experienced" his or her shoddy work they have no idea of his or her competence.

Even if they did have an unnecessary part fitted its unlikely they would want to pay for it.

They may not be told it was un-necessary to replace the item, if they believe the person is competent they may just trust him or her not to lie to them

That's the advantage of employing a professional.

Only if the professional really is a professional tradesman and not a professional con man ( or con woman ) with the necessary qualifications and cards to work in the trade.

 

[steve32]

Hi petit_pablo, thanks for your reply, can you please explain what you mean by "The main burner is backlighting at the injector" ?

The burner was removed and cleaned has something been missed? why would this affect the step flow gas release?

Regards

Phil

Backlighting is corrected by a good service and set up

What do you mean by step flow gas release

 

[Philip Payne]

Hi steve32, thanks for your reply, step flow gas release is where the gas valve releases a lower pressure at ignition to get the flames alight and then a few seconds later opens to release the full burner pressure. It's a means of reducing that initial whoosh of noise and combustion that some boilers have and makes for a quieter fire up.

However, how the step flow is achieved i've yet to discover.

Phil.

 

[Philip Payne]

Hi Agile (Tony) unfortunately I agree with Bernardgreen, it's a complete lottery whether you get a truly skilled gas engineer or a dodgy one, i've had a few dodgy ones in the past who just want to do a quick clean and vacuum and charge for a service they haven't performed. They may be gas safe qualified but that doesn't mean they are a competent engineer.
I'm an engineer myself and know that not all are the same in terms of knowledge and skills however they all like to be paid even if they can't resolve the problem.

Regards

Phil.

 

[45yearsagasman]

Call BG