The carbon monoxide leak was as a result of a broken valve which has since been replaced, and as advised to yourselves by BG it was not to do with the vent, which as I keep stating is within 90% of the requirement which as mentioned in the regulations brought in during 2008 means it is not necessary for an 'at risk' notice to be issued which is why we are making complaints to British Gas.
We understand your worry after the faulty valve, but nobody can help it if a boiler breaks down and we have put a BG policy into place which covers all gas, electrical and plumbing problems with a 24/7 breakdown line for the tenants convenience.
We have never once told the agent that we weren't willing to pay for any faults/breakdowns that may occur and if you are saying that is what he has said then perhaps you should take it up with him, as he is denying it to us.
We have been told that you are only without heating as you refuse to turn the boiler on. I can understand your worry, but BG confirmed that the ventilation wasn't the problem and as previously mentioned we are making a major complaint to BG as they issued the incorrect documents to you.
If you were worried, perhaps getting an independant gas safe engineer to issue you with a report to confirm your opinion that this should be 'at risk' would have been the best option, then you would have had no opposition at all, we would have had the remedial work done immediately and refunded the cost of your report.
But it is too late now isn't it.