Valiant ecotec - Hot water turning cold

[Spadez]

Hello,

I have a valiant boiler ecotec 824 that was service about 4 months ago but has suddenly had a problem where the hot water for either the shower or the taps will run hot but flick between being luke warm and hot.

The pressure is ok at 1.6bar. The temperature on the rads is low but water for taps is set to mid way up.

I have no error codes, either when not in use or during operation when it gets cold.

Any insight into what I can do to help diagnose it, or potentially improve it?

Thanks,

James

 

[DP]

Some checks required but may well be boiler fitted to dirty system (system not pre-cleaned before present boiler fitted). Service unlikely to have been a cause. What was done during the service or how long was the engineer in front of the boiler. A proper service, rarely done, is what the book require

 

[Spadez]

Thank you for the reply. I don’t really assume it was the service because it’s worked many months since, from my side I was just trying to make the point that we haven’t missed a recent service or the like.

Is there any checks I can do my end? From what I read it would be a blocked input pipe, or a motor pump issue.

If the pump was at fault I thought it would make a horrible noise when the water went cold but it doesn’t. I also thought I might see any error on the boiler but it’s reporting all fine.

 

[Spadez]

Any more insight?

 

[Harry Bloomfield]

If the pump was at fault I thought it would make a horrible noise when the water went cold but it doesn’t. I also thought I might see any error on the boiler but it’s reporting all fine.

It's a combi, so the CH water pressure and the CH circulation pump have no bearing on the problem with the HW.

 

[bernardgreen]

One probably reason is :---

The flow of water to the hot taps is not enough to remove all the heat produced by the burning gas so the boiler and/or the hot water is getting hotter than it should. At some point the boiler shuts down until the overheat condition has been removed.

I would have thought the overheat condition would have displayed a fault / error code.

 

[The831Bunny]

The plate heat exchanger, canoe filter, and/or flow tube could be blocked with debris. Various tests need to be carried out on the boiler. Contact the engineer/company that serviced the boiler, I'm sure they are better placed than a forum to help you.

It's a combi, so the CH water pressure and the CH circulation pump have no bearing on the problem with the HW.

On this boiler the correct primary circuit water pressure, and the correct operation of the pump is required for HW operation.