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Central Heating

Two new baxi boilers and still no hot water or heating.

Hi, hope someone can help?
A couple of weeks ago I noticed that my hot water was intermittent and I could only get hot water if a ran the tap very slowly, eventually the heating stopped working so we got a gas engineer in who said we needed a new boiler so we had a new boiler fitted (baxi combi boiler) after a few days the hot water did the same thing as the old boiler and then eventually the heating stopped working. If we tried to get it to work it would work for a few hours before a loud hissing sound would come from the boiler. We got the engineer out who said it was air so he bled all the radiators and it worked for a day before it had the same problem.
We had a baxi engineer out who seemed to have no idea what was wrong with it. He eventually said it was the pump fitted a new pump on our new boiler got it working and then five days later it did it again.
As you can imagine I was extremely frustrated with the whole situation so when they said they would fix it I said no and requested a new boiler.
They did fit me a new boiler last Tuesday and all was well and then tonight the exact same thing has happened on our third boiler. It can't be a just a coincidence, surely there is a fault outside the boiler causing the boilers to stop working. They seem to be overheating and no one has a clue what's wrong!

4 Answers from MyBuilder Heating Engineers

Best Answer

did they mention to you anything about blockage in your system?. I think your system needed only proper power flushing not boiler replacement . the sludge cause hydrogene gases in the system and if close to boiler will lead to overheat.
i live in north west london if you are close by i can come and have a look if i manage to sort it then i get paid .


Answered 11th Feb 2015

It sounds to me like the problem is in pipework and radiators. A build up of sludge maybe causing poor circulation which is why sometimes a Loud hissing noise can be heard. A Powerflush should sort all your problems out! Regards Andy


Answered 18th Feb 2015

I have found this fault after others have changed heat exchanges, pumps, etc. to be a faulting mixer tap/shower. Most times its a shower which has a fault with non-return valves in the body allowing cold mains to flow through the shower and towards the hot tap which is running, this then causes intermittent hot water production. try running a hot tap when faulting, and feel the copper pipe under the boiler if possible to see if its getting as hot as the display says. if not its likely you have an external shower/mixer fault. Another good test is simply to turn off the cold supply into the boiler on the inlet valve under the boiler, and then open a hot tap. There should be n flow from the tap. If there is flow, it proves there is a mixer shower/tap allowing cold water into the hot pipe in the wrong direction. Caught me out once or maybe twice, never again! Lewis Boiler Services.


Answered 14th Mar 2016

Bull , you got a major leak , causing pump to cavitate and overheat , along with a boiler that is known for not re setting and breaking down after overheat condition. The perfect storm , get in someone who knows what they are doing.


Answered 30th Mar 2015

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