Friend of mine has bought a flueless gas fire from B&Q. His corgi fitter
however says he would be reluctant to install it, even if all the critera
for room size, ventilation and use etc is satisfied.
Are there any corgi people here? If so what's your opinion of these fires.
Natural gas is principally methane (CH4). The products of combustion
CH4(g) + 2 O2(g) = CO2(g) + 2 H2O(l) (g=gas, I=vapour)
carbon dioxide and water. This is what you will be exhausting into
your living space. If your living space is well ventilated then I
suppose it could be claimed there is no problem although the
introduction of clean air will require more gas to be burned to heat
My view is this type of heater is best to be avoided. Corgi qualified
fitters have no specific expertise in this matter. It is simply a
matter of chemistry!
The report linked in one of the posts says that the maximum concentration
of CO was 22ppm. This was under extreme use that nobody would normally
put the fire to, and without the ventilation that the fire requires.
22ppm would at most give you a headache after some hours (but frankly
you'd have turned the fire off and/or opened a window long before then).
Besides which these are not intended as a primary source of heat.
The rules require them to be put in relatively large rooms.
If the fires are installed in accordance with the instructions and the
regulations there should not be a problem. Many registered fitters who
feel the need to defend their careers and livings simply won't go near
open flued or flueless appliances. There is no requirement that they do
work that they do not wish to do, most have more than enough work without
taking on extra "risks" .
The + for flueless are:
inherent high efficiency
The - are:
may aggravate condensation
 These risks, IMHO, are perceived rather than significant.
Wouldn't touch them with a bargepole, mainly because when I did my training
we didn't do anything about them, and one article in Gas Installer and the
Manufacturer's instructions don't give me sufficient confidence in my my
competence to install one safely that I'd risk a customer's neck and my
profession on it when there's plenty other work to do.
I don't know but hope that the composition of natural gas is
controlled by legislation. Even if it is the emission into a living
space by flueless devices depends entirely upon the gas meeting the
If the gas is pure methane then the likelihood of problems in a
ventilated room is likely slight, however, if any impurities are
included into the gas supply by design or by accident the resulting
emissions could be poisonous. Are you prepared to accept this risk, I
don't think I am.
No, I know the difference. Whilst I can and do make many typos I mean CO.
22ppm was the maximum recorded value. That's not going to give you more
than a head ache and that was the worst case.
No vents, left on 8 hours, etc.
The danger in these devices is that they are not inherently safe enough
to continue using if they are neglected and begin to burn badly.
The composition of gas is controlled by various standards and is mostly
CH4, some C2H6, some N2 and some CO2 + various other trace things.
There is little or no CO in the gas. The CO is generated by poor