Baxi Duo-Tec 28 Combi combustion noise

[jaydebruyne]

i fitted the above boiler last week, all was fine during commission, other than the supply being undersized a bit. Was getting 14mb at the gas valve, 23kW heat input on hot water and I think 2.8m3/h which is just shy of the required 3.2m3/h. Only this appliance on gas.

Got called back a couple days later due to a loud noise which wasn't there when I commissioned the boiler.

Basically on max rate only, there's a noise like wind being blown into the combustion chamber. Spoke to Baxi they said it's because the gas pipe is undersized and the burner is getting too much air.

In theory it makes sense due to the fact the fan governs the gas rate. But I thought it would just ramp down if there wasn't enough gas available, like every other boiler I've seen with undersized pipework.

I've told them the pipe needs upgrading but as per the fga the boiler is running fine.

 

[Scott_D]

14mb is pretty low!
What the working pressure at the meter?

 

[jaydebruyne]

14mb is pretty low!
What the working pressure at the meter?

Off the top of my head I think it was just over 19

 

[ShaunCorbs]

That's way out of spec mate

 

[jaydebruyne]

That's way out of spec mate

I've never heard a chamber making that noise before from undersized pipework..??

 

[ShaunCorbs]

I've never heard a chamber making that noise before from undersized pipework..??

Don't know but the problem is atm it hasn't got any warrenty as it's not fitted to spec

 

[jaydebruyne]

Don't know but the problem is atm it hasn't got any warrenty as it's not fitted to spec

Grrr when I surveyed for the boiler it was 22mm from the old boiler, soon as took some boxing off during install it went into bloody 15 under a tiled bathroom floor!

I get that it's under spec and I have to go sort the pipework out, I've told them this already, but I don't get the noise. They had a 28kW Worcester in there before which didn't groan on max rate. And every other boiler I've seen with undersized pipework hasn't groaned either???

 

[Scott_D]

I think the duotec dont like low pressures
Ideal and Vaillant can work ok down to quite low but its still not to regs

 

[jaydebruyne]

I think the duotec dont like low pressures
Ideal and Vaillant can work ok down to quite low but its still not to regs

So what's the best way to word this to the customer? They asked why their old boiler didn't make the noise at which I replied it's down to how the boiler is manufactured. But in terms of now charging to upgrade the pipework, do I charge normal rate? As this wasn't part of the original job..

 

[Scott_D]

The gas supply does not comply with gas regulations and is undersized
On the survey for quote I saw a 22mm gas supply but when boxing was removed if found it to be 15mm
I doubt you would have tested the inlet pressure on the old? was it even working?

Maybe say you cant register the boiler as it doesnt comply
I usually put something in my quotes like 'if the requires upgrading this will be at an extra cost'

 

[jaydebruyne]

The gas supply does not comply with gas regulations and is undersized
On the survey for quote I saw a 22mm gas supply but when boxing was removed if found it to be 15mm
I doubt you would have tested the inlet pressure on the old? was it even working?

Maybe say you cant register the boiler as it doesnt comply
I usually put something in my quotes like 'if the requires upgrading this will be at an extra cost'

It was working but not very well but no, never have tested the old inlet :/ will do from now on though, and put the caveat about the gas supply.
Well, it's a lesson learned the hard way so I will probably bite the bullet and just charge them for materials, it's not a long run so shouldn't take long.
Thanks for the advice everyone! Every days a school day! Lol

 

[Scott_D]

I wouldnt do it for free unless it was your fault.
Sounds like you were caught out by the hidden pipe, can you show them?

 

[jaydebruyne]

I wouldnt do it for free unless it was your fault.
Sounds like you were caught out by the hidden pipe, can you show them?

Yeah I can as it's now visible since the boxing is off.

 

[jtsplumbing]

Get the governor replaced on the meter as well could be faulty

 

[Scott_D]

Yeah I can as it's now visible since the boxing is off.

How did it go?

 

[jaydebruyne]

How did it go?

I'm upgrading the pipework on Friday Didn't charge full rates in the end but not doing it for free either.

 

[king of pipes]

Jay you need to sort the gas supply bud fitted loads of duo tecs never had a issue you cant have 19mbar at the meter and 14 mbar at the boiler as you are finding out besides being against the gas regs you know what needs doing as a GSR , upgrade the supply in size and get the governor on the gas meter replaced by centrica . cheers kop

 

[jaydebruyne]

Jay you need to sort the gas supply bud fitted loads of duo tecs never had a issue you cant have 19mbar at the meter and 14 mbar at the boiler as you are finding out besides being against the gas regs you know what needs doing as a GSR , upgrade the supply in size and get the governor on the gas meter replaced by centrica . cheers kop

As above, I'm upgrading the gas run. Just had to deal with stressed out customers who were stressing about floor tiles coming up. But all will be sorted. Also had a bad few days and made an error. But all will be fine once I've redone the pipe. I'll see what happens once I've done the pipe before I get the governor replaced. Cheers KOP

 

[ShaunCorbs]

What happened mate ?

 

[jaydebruyne]

What happened mate ?

Am going in to upgrade the gas run when they get back from a short break. They were just stressing about having floor tiles lifted etc and were worried upping the pipe wouldn't fix the noise etc etc so took a couple of days of trying to keep calm and patient before I got the green light.

 

[ShaunCorbs]

Am going in to upgrade the gas run when they get back from a short break. They were just stressing about having floor tiles lifted etc and were worried upping the pipe wouldn't fix the noise etc etc so took a couple of days of trying to keep calm and patient before I got the green light.

I wouldn't worrie over it mate sometimes things happen out of your control

Could you go external ??

 

[jaydebruyne]

I wouldn't worrie over it mate sometimes things happen out of your control

Could you go external ??

Unfortunately not, terraced house. Can't even go external inside the place - well, I could but I know they will have a fit even at the suggestion haha so I'll just stick with going under the floor. fingers crossed what I have in mind is doable

 

[king of pipes]

We all get them jay its easy to miss something on a survey , annoying but needs sorting bud i am sure when you do the above you will end up with a happy customer and your reputation will still be intact , i had a job where the neighbor reported me to gas safe over a plume issue turns out the boiler was fine but i missed the gas cooker didnt have a openable window or door to outside as the customer had put a lean to on the back of the house had to fit a permanent vent at my own cost, we are all human but it was not a pleasant experience having your work pulled apart by the inspector, but now we get on great now once he had seen 3 other jobs they can usually see you are working to a high and safe standard but if you can avoid it all the better good luck mate cheers kop .

 

[jaydebruyne]

Put in a new gas run last week - problem solved! Cheers guys

 

[Old Account]

Put in a new gas run last week - problem solved! Cheers guys

Thanks for letting us know.

Top lads here, they all helped and motivated you to keep on going. Very great success and thanks of the forum.

 

[king of pipes]

Nice one jay very rarely get a problem with a new Duo Tec glad you got it sorted mate all the best Kop