Ventilation for dfe fires.

[Reg Man]

Just because a DFE is under 7 kw does not mean it does not need added ventilation,all DFE's need ventilation unless otherwise stated by manufacturer and that ventilation shall be no smaller than 100cm2

Agree with you. British Standard 5871 part 3. All DFE fire installations require in a minimum 100cm2 free air ventilation unless the manufacturer for the appliance specifies otherwise. DFE fires less than 7kW may not require additional ventilation if the flue flow is greater than 70m3/h, manufacturer would have to be consulted before accepting this as acceptable.

 

[arran197]

DFE's require a MINIMUM of 100cm2. End. If the M.I.'s recommend more then it must be provided. If less then 100cm2 is needed. The adventitious ventilation does not suffice for DFE's. Are you sure it's a DFE and not and LFE?

 

[sparra1100]

all dfe,s have to have 100cm" regardless and as above if mi,s say bigger you go bigger but carnt be less than 100cm2 full stop

 

[AlexGas]

No, no, no...
OK, BS can be confusing...
Here's same thing in our good old TB from Gas Safe:

Technical Bulletin 041

Note 2: DFE appliances with a rated heat input less than 7kW (Net) will normally require a minimum of 100cm[SUP]2[/SUP] free-area ventilation, however, reference should be made to the manufacturer’s installation instructions, as some models may not require additional ventilation.

Note 3: DFE appliances with a rated heat input greater than 7kW (Net) and up to 20kW (Net) will normally require a minimum of 100cm[SUP]2[/SUP] free-area ventilation, (or as by manufacturer’s installation instructions).

It's in black and white. So, it can be less than 100 cm[SUP]2[/SUP] or none.

 

[GrahamM]

Mi's trump regs.

In the majority of cases yes, but with important issue such as ventilation requirements the Regs/Standards overrule.

Another example is, how many sets of MI's does it state the flue must be fully inspectable along it's run?

Sometimes we have to take a balanced view/approach between the MI's and regs!

Nothing is straightforward in this game. Even more so in recent years. We now have more and more MI's contradicting regs/standard and vise versa. Keeps us on our toes.:smile:

 

[ADM360]

I could be wrong but I though that you couldn't just cut a hole in the floor to give a vent to a fire, I was under the belive that if it was under the floor it had to be purpose provided ventalation and ducted directly from out side to the vent!!

 

[kirkgas]

I could be wrong but I though that you couldn't just cut a hole in the floor to give a vent to a fire, I was under the belive that if it was under the floor it had to be purpose provided ventalation and ducted directly from out side to the vent!!

floor vent only needs to be ducted if under floor communicates with more than one property or there is a potential for radon gas

 

[ADM360]

Thanks Kirk, I though someone would put me right!!

 

[sparra1100]

to be honest i couldnt care less what anyone says as on my acs its said 100cm2 and says the same in the corgi book and viper book so as long as i cover my own rear and no one dies al stick to what ive been taught granted the mi,s overule everything but its been 100cm2 for as long as ave been doing it and this is the first time anyone has questioned it so all i would say is if someone wants to take the risk so be it on there head but i no what i would do

 

[AlexGas]

to be honest i couldnt care less what anyone says as on my acs its said 100cm2 and says the same in the corgi book and viper book

Sorry mate, you have to read the books again.

CORGI book (page 72) For DFEs - check the MIs as some models may not require any additional ventilation - or as per MIs.

VIPER (page F-4) Decorative fires may not need purpose provided ventilation where the MIs clearly identify this.