Prompt response to our enquiry, visit arranged next day, Dean phoned before arrival and set about servicing the boiler. He checked the faulty radiators and got them warming properly, and advised changing the valves, which were sticking. He agreed to return to replace the three valves and complete the seal on the fume outlet. He was polite and helpful with advice. He got on with the job and was done in about 90 minutes. We will certainly call on his services again.