Glow worm ultra com 18hxi whistling noise

[revans007]

We just had our boiler replaced with a glow worm 18hxi. after a few days it started making a loud whistling noise after it starts up. The noise lasts for about ten minutes. It was doing it at different times of the day but now it seems to do it in the morning first time it lights. I called out the installers and of course it didn't make the noise for them. It may be that the outside temp. plays a role as we have had cooler weather when it was whistling more often. Quite an annoying sound, like when you rub a wet finger around a wine glass. I have read other posts on this forum about this problem but have no real solutions or causes, just theories.

Any ideas or resolutions?
Thanks

 

[Agile]

There can be different causes.

Either water or combustion. The latter will be more evident when listening at the flue.

What speed setting is the pump on? If 1 or 2 then increase it to the higher setting and see what effect that has.

Did the installers power flush the system?

Did they check the combustion with a flue gas analyser?

Tony

 

[revans007]

Thanks for your reply Tony. I checked the pump and it is on three. I set it to 2 for a minute and then to 1 and back to 3, but it didn't seem to make any difference. I don't know if the system was flushed or not and the guys who came out when it wouldn't make the whistling noise didn't do anything except turn the max temp. to 70 from 80 and tighten the cap on the plastic elbow of the chimney. it only seems to do it when it starts up after it has been off for a few hours. This afternoon I made the noise and the LED temp. said 37 deg. which I presume is the current water temp. in the radiators.

There can be different causes.

Either water or combustion. The latter will be more evident when listening at the flue.

What speed setting is the pump on? If 1 or 2 then increase it to the higher setting and see what effect that has.

Did the installers power flush the system?

Did they check the combustion with a flue gas analyser?

Tony

 

[Agile]

I suppose it was all installed within a day, not power flushed and not checked with an analyser! Typical poor quality install. Probably paid just a low amount with cash!

Leave the pump on "2".

Did you listen at the flue?

Tony

 

[revans007]

Defiantly a gas sound not a water sound. It made the noise today and I went out side and put my hand over the small inner plastic exhaust vent pipe and the noise stopped. when I took my hand away it started up again. I think the fact that it happens when it first starts up means that since it is condenser boiler there is more condensation building up in the exhaust system and heat exchanger. Some how this causes whistling vortices in the exhaust pipes. Our local Council hired a contractor to replace the old boiler so I will have to call them yet a fourth time in one month with to fix the heating. I think the thing must have a warranty but this annoying problem.

I suppose it was all installed within a day, not power flushed and not checked with an analyser! Typical poor quality install. Probably paid just a low amount with cash!

Leave the pump on "2".

Did you listen at the flue?

Tony

 

[mickyg]

its the combustion causing it. Get your installer to adjust the high and low CO2 to 8.5% and it will go away, or call glowworm and they'll do it for you under warranty.

 

[Agile]

Why should Glow Worm come free of charge just because some nupty installer did not commission and set up the boiler correctly?

That means that everytime I buy one of their boilers part of the price that I pay is to cover dealing with their nupty installers!

 

[bell824]

as a g/w engineer i would not advise seeting the co2 to 8.5 a little to low if you read the books.
Also it is up to the installer to check the low and high co2 at commisioning as all through the UK we have different cv values in our gas therefor a factory setting may be good for lands end but not john o groats.

 

[mickyg]

as a g/w engineer i would not advise seeting the co2 to 8.5 a little to low if you read the books.

then you'll know that its fine and thats the best setting to make it quiet
you'll also know this is a regular issue on 18kw group service heat engines

 

[mickyg]

Why should Glow Worm come free of charge just because some nupty installer did not commission and set up the boiler correctly?

That means that everytime I buy one of their boilers part of the price that I pay is to cover dealing with their nupty installers!

The installers done nothing wrong, your jumping to conclusions as usual, everyones a numpty of course
They make the noise even on the correct setting. Me and my old tech eng came up with the figure 8.5-8.6% after some experimentation. Perfect everytime, doesnt affect the gas rate and makes the noise go away.

 

[bell824]

as a g/w engineer i would not advise seeting the co2 to 8.5 a little to low if you read the books.

then you'll know that its fine and thats the best setting to make it quiet
you'll also know this is a regular issue on 18kw group service heat engines

never had the issue i'm affraid will check it out though with other guy's.
if you are a g/s engineer then maybe your correct but i havn't had the problem and would never set this low

 

[mickyg]

as a g/w engineer i would not advise seeting the co2 to 8.5 a little to low if you read the books.

then you'll know that its fine and thats the best setting to make it quiet
you'll also know this is a regular issue on 18kw group service heat engines

never had the issue i'm affraid will check it out though with other guy's.
if you are a g/s engineer then maybe your correct but i havn't had the problem and would never set this low

Trust me its fine. Yes I used to work for GS, as did alot of guys on this forum. Maybe you need to understand combustion better rather than just worrying about whats written in the book.

 

[bell824]

well maybe i need educated on the characteristics of combustion then! lol cheers micky

 

[bell824]

so just on question wshat happens when gas and air don't mix corectly?? in my ten years experiance it normally means efficiency being dropped and poorer levels of combustion, then again i dont have a chemistry degree!!

 

[mickyg]

so just on question wshat happens when gas and air don't mix corectly?? in my ten years experiance it normally means efficiency being dropped and poorer levels of combustion, then again i dont have a chemistry degree!!

best discussed in cc. I wouldn't normally give out comb figures here, but only did it as they're not in the manual.