Trianco 25/40 Back boiler - Ventilation??

23 Jan 2006
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United Kingdom

My back boiler manual states that "The total ventilation required for the back boiler unit complete with any of the specially designed gas fires (which I have) is 65cm2.

How do the new laws coming in affect this. I assume that I will have to increase the total ventilation to comform to the new laws.

Q. What does the new regulations recommend for my boiler?
Q. Can I install a larger vent myself?

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You can fit larger vent if you want. however if your boiler and fire is working fine and have passed spillage test,etc then old vent is classified as NCS = not to current is not dangerous nor illegal.
The current vent is 8" x 5".

The guy who came round to service it late last year said that the vent was no longer to current standards but I thought the law was changing this year :?:

He didn't service it as he said that he would have to turn it off and thus we would have no heating (on the basis of the vent not being large enough)
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The free area of the vent must be 65cm, it may well say on the vent how much air it passes. If not you can work it out yourself by measuring the area of one hole then multiplying by the number of holes.

Example: 1 hole = 8mm x 20mm = 160mm x 10 holes = 1600 / 100 = 16cm2

If the vent provides less than 40% of 65cm it will be classed as AT RISK
If it is between 40% - 90% then it is classed as Not To Current Standards at the moment, AT RISK from 1st June.

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