Gas fire, ventilation, cavity wall insulation

[Caz6]

Can anyone tell me where I can find the official guidelines around cavity wall insulation, gas appliances & ventilation.

I have a gas fire where the chimney removes the fumes and is 6.9kw input. In the past I've been advised I need a vent fitting but reading on forums etc, this is only needed for fluless appliances over 7kw. Than have a vent fitted in our warm air heated house, I'd sooner get the fire (which is mostly unused) disconnected. But I only want to do that if absolutely necessary.

I'd like a link to the official guidelines show I can show a surveyor coming tomorrow if necessary.

Thanks in advance
C

 

[PrenticeBoyofDerry]

All the information you require is here, you are allowed to calculate 7kW as a deduction for adventitious air. But an assessment must be made with regards to adventitious air. It maybe that your property is lacking this.
http://www.hseni.gov.uk/l56_safety_in_the_installation_and_use_of_gas_systems_and_appliances.pdf
http://www.radmidlands.co.uk/Downloads/VentilationDom.pdf

 

[Caz6]

Perfect, thanks.

 

[picasso]

Depends on your gas fire and a spillage test before you can say no vent required .

 

[simond]

Yep, some fires say you must have air brick. Your internet forum advice referred to in the first post is wrong, it isn't that simple.

Also, with a warm air system there's air movement going on which as Picasso suggests, could well compromise the workings of a natural draught chimney. I'd suggest you'd want to do a spillage with the door open and shut, to allow for the influence of the return air path.

Easier to remove the thing.

 

[FiremanT]

You would be best to obtain / download a copy of the gas fire manufacturers installation instructions. Basic vent requirements will be n there, to show the surveyor.
But remember that "no vent required" is subject to satisfactorily passing of tests.

And +1 to the statement that your OP internet forum received advice is wrong

 

[ollski]

+1 to manufacturers instructions. Usually these fires are kept at 6.9kw to avoid ventilation. The issue with warm air is that it has a great big fan which can affect flue pull and needs to be tested by a decent rgi

 

[Agile]

The fire manufacturer's instructions don't apply to rooms with warm air heating or any forced air circulation.

The effect of anything like that has to be assessed by the fire installer or servicer.

The first post here contains some incorrect and potentially dangerous information particularly in relation to flueless fires.

Tony

 

[muggles]

Can anyone tell me where I can find the official guidelines around cavity wall insulation, gas appliances & ventilation.

I have a gas fire where the chimney removes the fumes and is 6.9kw input. In the past I've been advised I need a vent fitting but reading on forums etc, this is only needed for fluless appliances over 7kw. Than have a vent fitted in our warm air heated house, I'd sooner get the fire (which is mostly unused) disconnected. But I only want to do that if absolutely necessary.

I'd like a link to the official guidelines show I can show a surveyor coming tomorrow if necessary.

Thanks in advance
C

ALL flueless appliances, regardless of output, require a vent

ALL flued gas fires over 7kW require a vent

SOME flued gas fires under 7kW require a vent, and the manufacturers instructions will provide guidance on this, but will usually say something like "ventilation is not normally required", as there are situations where ventilation may be required, such as where there are extractor fans, ceiling fans, or warm air units installed. This will be down to the installer to assess, sometimes after the fire has been installed

 

[FiremanT]

Mugs is spot on.

Tony, the MIs DO apply to rooms containing warm air units - they are covered under the requirenebt to test. Any RG should know how this applies.
The OP's problem is that insulation surveyors are apparently expected to check on ventilation, but, from my experience,they do not fully understand the requirements.
The MI's wil be usefull to show the surveyor to avoi them running to default. We will "know" that certain fires are NV, whereas thet will asume the opposite.

OP: do you have the fire serviced? If not do so, and get the RGI to specify on his invoice or report that the fire has been tested with regard to WAU an airmovent. If you do, yuor RGI may, for a fee, forard you some supporting evidence to show the surveyor.

 

[gas112]

Other things that will affect the safe pull of a flue is ceiling fans both in forward and reverse ,extractor fans in adjacent rooms including tumble driers