The response was quick but we would never use them again. The engineer left with the boiler making an awful noise because he had left it on maximum power which we had to adjust ourselves. He also left so many bits and pieces behind (rubbish?) that we will have to call our own plumber now in order to find out if they are actually essential. When we called the company to have the engineer back (under guarantee, of course) because we weren't sure the boiler was safe, the lady on the phone was so rude that my husband decided to call our own plumber instead of dealing with Worcester Bosch again.