Aged 69 and having our first power flush. no i don't mean me you fools.I mean our central heating ,it has been playing up making a very funny noise like a swarm of bees.It seems to be a common problem.So at no cost to us we had a pump fitted,that has not worked,we were advised to go for a flush so that is happening this morning,he has just phoned.If this does not work and we think it won't,but it will do the systemgood,it's going to be a phone call to the boiler company and we both think it's a diverter valve,Google is a mass of good info,and other people have solved the same problem by going down that route.Wish us luck.A few 'undred quid is going down the drain this morning and over the next couple of days,chemicals get pumped in and then flushed and left in again.