Probably a roof mounted water heater. a friend has one and seems to hardly
use any gass.
Brian

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The Sofa of Brian Gaff...

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On Tuesday, 23 April 2019 21:44:06 UTC+1, Davidcorlett wrote:

Hi all.
I have done several adaptions to my boiler including supplementing the
central
heating with a hot pre feed so my boiler runs 100% on the external source
via
a plate heat exchanger.

What is this 'hot prefeed'. What is this 'external source'.

This has worked extremely well over the winter, and
the same heat source will be heating the pool ( when I set it up sometime
soon
). I have been toying with the idea of linking onto this loop for a
second
time, that's already in place, using another plate heat exchanger to run
the
hot water for the house. The loop can run at anywhere from 62 degrees up
to
around 90 degrees c depending on my choice and I was thinking that if I
can
link into my cold feed in ( the same as I have linked into the CH loop to
put
hot water pre boiler ) I should be able to stop the boiler firing up and
therefore use no gas.
I have read what feels like hundreds of articles but I cannot find whether
or
not I can do this on my old boiler.
Has anyone tried this before or can I simply not feed hot water into the
boiler?

Hope someone can help.
Thanks
David

There's no harm is having another heat source in your CH primary loop of
course. As for the cold feed I don't know, can you examine/identify the
materials in the relevant part of the boiler? Is there a fault code in the
manual for input too hot? What will it modulate down to? How are you going
to control temp for legionella safety?

There are others here with much more knowledge & experience on heating
systems. But the website you're using is blocked by most folk here. You can
get here via google groups or a newsreader.


NT