Plumbing

Hot water only when more than one tap is on

Anonymous user 23/02/2024 - 3.35 PM

Hello all, We have an Ideal Logic 35 Combi boiler (7 years old) and after changing the shower mixer and the kitchen tap, I am experiencing some issues with it. Both the shower and the kitchen tap, will, a lot of the times, fail to fire the boiler up. The shower mixer is a bit better, as in it would get the boiler fired for a few minutes but then would go 'ice' cold - that's when I need to turn the bathroom tap on, then both will get warm and stay warm. If I turn the bathroom tap off, the shower mixer will eventually get cold again in a few minutes. Leaving both on is a solution, but then the shower is quite weak - not the best way out. The kitchen tap situation is quite similar, except that it rarely fires the boiler up at all. I need to go into the downstairs loo, turn the hot water on there and then I get hot water in the kitchen - for a short time. I assume the new fixtures have slowed down the flow of water and the 'demand' is now not strong enough to 'wake' the boiler up - is that a fault of the fixtures, or should the boiler be able to handle that? The 'not hot' water flows at a pretty good rate, but probably not as strong as with the old fixtures. Was thinking of the diverter valve, after some googling, could that be it? Not a DIY job, I assume, unless I can spray some 'boiler WD40' to get it to move more freely or something of the sort? Any other suggestions appreciated, will probably be calling a plumber/heating engineer sooner rather than later as it is becoming a major inconvenience. Thanks, Serge