Cowl for gas fire

[Caroline Higgins]

Chimney cowl ..I’m not sure whether this is the right place for this question
I’ve got 3 chimney pots . 2 closed and one for a gas fire . I have included a photo of the pots with the cowls.. my question is about the cowl on the crown chimney which is for a gas fire. Is it correct . I was told it’s ok resting on the points and that the spaces between the points will be enough . Thank-you

 

[oldbuffer]

Needs a smoke test of the fire itself.

 

[Terrywookfit]

That is not a suitable termination for gas.
It is for ventilation only.
The holes should admit a 6 mm ball but not a 16mm ball.

 

[DP]

Chimney cowl ..I’m not sure whether this is the right place for this question
I’ve got 3 chimney pots . 2 closed and one for a gas fire . I have included a photo of the pots with the cowls.. my question is about the cowl on the crown chimney which is for a gas fire. Is it correct . I was told it’s ok resting on the points and that the spaces between the points will be enough . Thank-you

View attachment 230135

something like this

 

[dilalio]

https://www.upperplumbers.co.uk/plumbing/plumbing_pages.php?title=Flue Terminals&cat=1

 

[Madrab]

As suggested I wouldn't be happy with that terminal if it was me fitting the fire. That being said your gas safe engineer, who's installing or servicing the fire should be able to confirm. Either that or your chimney professional will be gas safe or have a gas safe resource and they should be able to confirm.

 

[Caroline Higgins]

Terrywookfit sorry for my misunderstanding do you mean smaller holes like in the cage type someone posted above thankyou

 

[Caroline Higgins]

ventilation

Sorry does this mean smaller holes like the picture shared above with a birdcage Thankyou

 

[Gasguru]

Traditional brick built flues are 9 x 9" but your flue may have been lined with a flexible liner.


From BS5540-1

Any chimney with a flue of 170 mm diameter or less should be fitted with a terminal conforming to 5.1.5.
Chimneys with a flue diameter larger than 170 mm, (built for solid fuel appliances) and using a chimney
pot do not require any other terminal when they serve a gas fire.

Where there is evidence that a chimney is used for nesting by birds, squirrels or other wild life etc., or there
is such a known problem in the neighbourhood, a suitable guard or terminal should be fitted to the chimney
to prevent entry. This is particularly important in areas where birds such as Jackdaws are known to
roost.Before fitting a terminal or guard the chimney should be inspected, and where necessary reinforced, to
ensure it will support such a terminal or guard. After fitting a terminal guard, the appliance should be
checked for spillage to ensure that it is clearing it’s products of combustion.

5.1.5 Terminal design

When the diameter of a flue is 170 mm or less, a terminal conforming to BS 715, BS 1289 or BS 7435-1
and -2 shall be fitted.
Where a proprietary terminal is not used, the total free area of outlet openings on the termination shall be
at least twice the cross-sectional area of the flue. Outlet openings shall be such that they will admit a 6 mm
diameter ball but not a 16 mm diameter ball. The openings shall either be uniformly distributed around
the termination or arranged at two opposite faces.
The free cross-section area of the terminal shall be appropriate for the appliance installed to the chimney.

COMMENTARY AND RECOMMENDATIONS ON 5.1.5
The free cross-sectional area of the terminal may be smaller than that of the flue as long as it is appropriate
for the appliance

https://brewercowls.co.uk/crown-birdguard

It's essential you have a correctly installed carbon monoxide alarm with a gas fire.
The fire MUST be spillage tested after any terminal work.
If that fire has been serviced I'd expect you to have some paperwork showing non compliance of the existing terminal.

 

[Caroline Higgins]

It's essential you have a correctly installed carbon monoxide alarm with a gas fire.
The fire MUST be spillage tested after any terminal work.
If that fire has been serviced I'd expect you to have some paperwork showing non compliance of the existing terminal

Thankyou Gasguru
We haven’t used the fire with this cowl . We have been having some work done on the chimney consisting some small shrubs removed and some pointing done.
the builder put this on but I wasn’t convinced it was correct so sent my son out to take some pics with his drone .
Up untilnow we had used the gas fire with no cowl .
we have had smoke tests done in the past with no cowl just the crown pot. We have carbon monoxide detectors.
I have told him to take it off and if ones going on it will be a correct one
We do get some debris down the chimney as we live opposite a large park so have plenty of wildlife around .

 

[Gasguru]

Unfortunately builders blocking flues and leaving customers at risk is very common.
It's up to you what you do next....a phone call to the HSE would be appropriate in order to protect his future customers (and previous).

https://www.dailymail.co.uk/news/ar...-fumes-negligent-builder-blocked-chimney.html

Carbon monoxide detectors...I hope you don't mean those pointless square cards that change colour.

Most gas fires are designed to combust the gas very inefficiently in order to give a yellow flame picture...so much carbon monoxide is produced that our flue gas
analysers (that we use to set up boiler combustion) would be overdosed. Fires are the only gas appliance permitted to burn gas in such an unsafe manner.

Before the scaffolding comes down I would advise you have the fire and flue fully tested by a registered installer (and a suitable guard fitted).

 

[Caroline Higgins]

We have the kidde alarms in the room with the gas fire and where the boiler is.
I have a gas safe fitter coming tomorrow to do some other work so I will get him to check the fire and chimney again. I will have a word with him and we will order a guard suitable for gas and a crown chimney . Thankyou for all the links . I didn’t feel comfortable with what he was putting up there and had a nagging doubt it wasn’t right . You have really helped.

 

[Caroline Higgins]

https://brewercowls.co.uk/crown-birdguard
gasguru thanks for the link I will have to do some more research as the crown chimneys are a different shape . Ours look like this but not broken .

 

[Terrywookfit]

Which Fire do you have fitted?

 

[Caroline Higgins]

It’s a living flame gas fire