Chimneys using solid fuel, oil & gas need regular chimney cleaning, servicing & inspection.
Many people fail to sweep their chimney or service appliances often enough, either through neglect, not understanding the necessity, or for financial reasons.
Of all carbon monoxide deaths in the UK 32% are solid fuel related, 37% are mains gas related.
(statistics of deaths produced by kind permission of CO-Gas Safety)
It is essential that you do not allow soot, fly ash, vermin nests or other matter to build up where it can prevent or hinder smoke and the products of combustion passing safely out of the flue. Please read manufacturer's instructions, as some appliances require internal flues clearing every 4 weeks when in use and prior to lighting.
Air Supply
Do not make the room airtight because the heating appliance can start to deplete oxygen levels & this is dangerous to anybody within the dwelling. You may need an extra vent or air bricks to provide extra oxygen for the appliance
Servicing
For safety reasons have your appliance serviced at the manufacturer’s recommended intervals by qualified tradesmen.
Never block existing vents or air bricks, or appliance flue ways.