Servicing a Baxi Bermuda Back Boiler Much of the work doesn't involve the boiler: it is concerned with the flue and ventilation, and with cleaning and servicing the gas fire. The flue must be inspected throughout its length that means in the fireplace, upstairs, in the roof space and outside. And the ventilation must be checked that means searching for the correct ventilation grills to outside, and checking that the airway is big enough, not obstructed and has an acceptable route or ducting. When I do a second or a subsequent service on a Bermuda I don't have to spend time looking for vents which may not be there because I made sure they were there last time. Nor do I have to spend time convincing the customer that the missing vents are a big deal when he thinks it doesn't matter. There is more about ventilation here. The point is, an initial service often includes a fair amount of time searching for vents and clearing things out of the way in the loft to get access to the flue fo