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Instant water heater with preheat?

Postby Phill S » Sun Dec 27, 2020 1:40 pm

Afternoon all,

I'm trying to help my parents to get their house renovated. One thing I think would benefit them hugely would be to upgrade the hot water system.
It's pretty convoluted. They have a gas Rayburn, a wood stove with boiler, and an electric heater in the hot water tank. This all goes into the usual header tank in loft, insulated water tank in a cupboard system. Certainly plenty of redundancy, but all these systems take ages to heat the water up. I'd like to find something to give instant hot water, like I get in my house with a combi flash boiler.

What I would like is something that is fed from the hot water tank. If it is not hot enough, it heats it, if it is hot enough, it leaves it. This would be supplying hot water for baths, showers and to the kitchen.

I do not want to do anything to the radiator system, it works fine as it is. This makes a combi boiler unnecessary, although I suppose if we found one that can deal with preheated feed water then we could either not use the central heating side, or put in one or two radiators in separate systems.

I've tried internet searches, but am not really sure what I ought to call it.


Phill S
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Simply Build It

Postby stoneyboy » Sun Dec 27, 2020 11:02 pm

Hi phill S
Your best option is to leave the immersion heater on all the time. Fitting an instantaneous heater into the system is not an option because your system is tank fed.
Regards S
Rank: Project Manager
Posts: 4946
Joined: Wed Dec 10, 2008 6:44 pm

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