Back boiler ventilation

12 Jun 2012
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United Kingdom
We have a Baxi back boiler situated in a draughty living room (67 mtr cube) between a kitchen (48 mtr cube)and another Larger living room (108 mtr cube). The flue is ducted up one chimney stack and is ventilated at the top to keep it dry. The kitchen has a ventilated hood which is never closed. Their is a permanent opening between the boiler and kitchen (0.38 mtr sq) and the boiler and living room 2 (0.022 mtr sq).

Recently a meter engineer came to change the meter he said we need ventilation for a our boiler. can this be placed in the ceiling and vented at the soffit.

They also want the meter moved outside an open vented porch. In the process they want to cement over an air brick to a suspended floor.

Finally, they say the meter is not bonded, but the British Gas Engineer who approved system was happy it was under an internal floor.
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Are you sure there isn't a combustion vent already. Maybe unclosable vents on the window or a vent on the wall or floor? If a Bg engineer was round I believe they would have noticed there wasn't any as for one, ventilation is one of main safety concerns with open flued appliances and two, it would be an opportunity for them to give you a ridiculously priced quote to fit one.
No there is no ventilation other than the cooker hood, the outer casing of the boiler up the chimney stack and through draughts between rooms. We however do have closable ventilators above both doors in the living rooms. The main draft is from a front door in a hallway that never feels warm.

The pilot flame on the boiler is always the correct colour. The great advantage of that technology is a power cut does not switch all heating and cooking facilities off.

My main concern about a wall vent is the plastic vents are so ugly. I could use the roof space and duct a vent out through the soffit.
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Yes its fine to vent through roof space, remember to use correct vents for adequate 5-10mm spacing of slats etc. You may not even have to duct it as long as there is nothing obstructing the ventilation path, ie insulation covering vents to outside.I think there was a change in building regs so that if there has been any work done in roof since 1985 there should be correct vents on soffit already. Maybe someone else on forum can confirm this?
Bearing in mind you have a cooker extraction unit in kitchen and a permanent opening between rooms,I would advise you to get a gas safe engineer to check appliance for spillage as any extractor fans can affect the pull of the combustion products up the chimney.

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