My combi boiler (which was serviced just 4 weeks ago) heats the house well. However, I have a problem with the hot water. Runs hot for a couple of minutes then gets gradually colder till its like turning on the cold tap. Let it run for a few minutes then it gradually heats up again. Can't even get a basinful of hot water for the dishes never mind a bath. Any ideas?
There's usually a control on the boiler that lets you alter the temperature of the rads and the hot water (2 separate controls).
Also, try running the hot water a bit slower. You'll find the slower you run it - the hotter the water gets (up to a max temperature, after which, it'll make no diifference).
Maggie. I had a perfectly working boiler until a service and then had exactly the same problem as you. Took ages to sort with lots of visits but turned out to be something the first engineer had done wrong. I recall I was told it was something to do with the heat exchanger but by the time it was sorted I had lost the plot.
There's probably a small amount of hot water storage in the boiler Maggie. It's kept topped up. When you turn on the tap, that amount is supposed to get you going before the burner kicks in and starts delivering the flow.
Either your heat exchanger is slow, or maybe a control sensor is faulty.
You need to get the guy back again.
Mine has always been like that too. Maybe your gas engineer turned down the water temperature lower than how you'd like it to be. I like mine at the maximum but it's still not as hot as I'd really like it, and I disable the eco setting, it seems to make very little difference.
Thanks folks. The Builder - that sounds exactly what happens, get a small amount of hot water but unfortunately the burner does not kick in so it then runs cold. End up boiling a kettle to wash dishes! Engineer coming Monday so fingers crossed.