Twice over the last 18 months I have asked British Gas engineers out to do a service ( not a reporting a fault) for a boiler and twice the boiler has broken down hours after the service was completed . Until the two visits these boilers had been working .In one case not very well in an old system but still functioning and in the other a boiler only a year old and working perfectly. I find this incredible .All this can be verified by British Gas service records .In neither case had I touched the two boilers concerned .For a period of ten years previously I had no complaint with the service I received from British Gas and I am baffled at to why this should suddenly have changed .