I feel a little guilty about this one. Last year 2005 I was asked when I had time to look at a gas fire that had not been serviced since they had moved in. I was also told they don't often use the fire so there was no rush. In Oct of 2006 after servicing their boiler I looked at the gas fire. When I removed the fire and closer plate things were not looking good and the photo does not do it justice as the room is full of smoke and it is one of the times I never asked for a bowel of water (to put the smoke pellet in) Regulation advises that I heat the flue and re-test, but before I did I thought I would see if any of the smoke had reached the top of the chimney, the customer told me it had so I had a look!

This is what was found! an air brick at about 7 foot six inches which is very good for letting air into a property, but this gas fire was under 7Kw so it was not really needed, but again the photo does not do it justice as it had some smoke coming from the air brick.

The builder in the 70s felt this was good enough for a single gas fire flue (chimney)