Potterton Profile60 Netaheat Problems

[synergy]

After switching on , the main burner on my boiler goes out after a few minutes but the pilot remains lit. It will not re-start until it has cooled down.

Reading about it suggests a fault with the gas valve (White Rodgers) but I am puzzled as to why it starts correctly from cold and how can the heat affect it.

Any clues please?

 

[cozzmic]

Heating engineer time I'm afraid as this is a positive pressure case boiler.
Could be several things but it could involve the gas train or case so you can't safely touch it unless your qualified.

 

[synergy]

I do understand that side of it. It is just a matter of finding out what is wrong, can it be fixed and the cost. The bolier is 15+ years old and had 2 changes of the PCB.

 

[Ronald0]

As you say, once the call from the external controls is lost and the main burner shuts off, the pilot will normally extinguish.

To verify a gas valve fault a qualified engineer will check for the presence of a voltage at the main burner solonoid in this situation (when there is still demand from room and/or cylinder stats).

 

[synergy]

Hi Ronaldo

Sounds like an expensive option especially for a boiler of this age. Can you recommend a realiable heating only (open vent) 24/25KW boiler? Last autumn I was looking into Viessman & Vaillant as preferred options but maybe by now there are even better ones out there.

Any advice will be appreciated.

 

[kevindgas]

the vaillant 400 series are designed for open vent and are a lot smaller in size than the neataheat.
you can also get the £400 scrappage allowance on this boiler so maybe a wise time to bite the bullet!!

 

[synergy]

Thanks kevin

You did not mention Viessman. Last year when I was looking into this matter it seemed to be the buzz word. To be honest, I am quite happy with a Vaillant myself. I know I will have to bite the bullet. With this scrappage allowance you mentioned, it may not hurt as much. I just hope this boiler will not require the existing 22mm pipe work to be up-sized to 28mm.

 

[Agile]

The solenoids on that model could possibly be going open circuit when they are hot. But it could be other things.

What happens if you leave it for a long time in the faulted mode?

Does it relight later?

Tony

 

[synergy]

The solenoids on that model could possibly be going open circuit when they are hot. But it could be other things.

What happens if you leave it for a long time in the faulted mode?

Does it relight later?

Tony

Thanks Tony for your time. I would like to know the cause of the problem. It has been left running in the failed state via timer/programmer for over 10/15 minutes without any change. How much longer do you think it should be left on? Could this be something to do with the heat of pilot?

 

[Agile]

To enable a boiler to completely cool down it can take at least an hour!

We dont give gas related advice which might encourage a DIYer to do gas work.

Changing a solenoid on a gas valve is a slightly grey area although my opinion is that it is definately "gas work". So is changing a PCB when that has gas settings which need checking/reseting.

Its for everyone's safety!

Tony

 

[synergy]

Hi Tony
Thanks again for your reply. I have no desire to mess around with Gas issues. I am one of those people who like to know how things work and what makes them go wrong.

I have been looking at Vaillant boilers for open vent systems. Their output jumps from 18kw to 28kw. My present boiler is 60KBTU which I think is equal to 18kw. The main pipe work is 22mm. Will this require to be changed to 28mm for a 28kw output?

 

[kevindgas]

Thanks kevin

You did not mention Viessman.

thats mainly due to never having used them. my mate uses them and seems to like them though.

the vaillant boilers can be range rated by adjusting D.0 in the display so just get the size above your needs and reset it to suit.

i allow 1.5KW per rad and 2 for cylinder this usually is ok but you can up it by a kw at a time if it struggles.

 

[synergy]

Hi Kevin

Since my garage conversion, my current boiler (18kw) is a bit too small. Ideally I wolud like to have a 24/26kw output at my disposal. Will my present 22mm pipework will be sufficient?

I was told that pipework would need up-sizing for a 30kw boiler.

 

[synergy]

What happens if you leave it for a long time in the faulted mode?

Does it relight later?

Tony

Well I did leave it on for more than 1 hour with the pilot and the fan running but still no fire in the main burner.

 

[synergy]

It was diagnosed to be a faulty main burner solenoid. Bad news was that it is no longer available. The alternative is to replace the whole gas valve which itself is discontinued (a compatible Honeywell valve is available).
All this appears to be costly for an aging boiler and I have decided to have it replaced.