We had a problem with our boiler.
When you ran the hot tap there was a terrible vibration and very noisy.
We reported it to the site office and the next day they came, drained the tank down, thinking it was an air lock, refilled it but it was still the same. Next they took the taps off the wall, the boiler was off and on the balcony and the tiles came off.
They packed around the pipes with expanding foam and when it was dry put everything back together.
This did not solve the problem the first time so they were back again and repeated the process.
The problem has now been solved and the workmen completed the work until they were satisfied.
Sue.