DIYbanter - View Single Post - heating / hot water

www.GymRatZ.co.uk[_2_]

On 08/03/2016 07:49, wrote:

any advice gratefully received. thanks

What I did was....
Get a decent combi based not on heat out-put but water flow capacity.
i.e. big enough to drive 2 showers at once. This gave me a boiler with
more than enough capacity to meet current (time of install) and future
(the new extension that wasn't on the cards at the time) demands.

IIRC my boiler is 36Kw which is plenty man-enough to give 2 good showers
simultaneously. Fitting something like "Mira Eco" shower heads to both
showers come in at a miserly 7 litres/minute draw per shower with the
"feel" of a much larger flow due to aeration of the water.

Weather compensation on the boiler is a must-have in my mind and if you
can run your system at UFH temp and still maintain comfort levels you're
onto a winner BUT if you find you have to run significantly hotter
you've got that big-boiler backup and you'll still modulate down to UFH
temperatures during spring and autumn anyway.

Planning a system based on the most extreme conditions expected is
completely wrong to me. If you're charging someone to do their heating
then yes it makes sense as you'd not want people saying their house is
too cold even if it is just a week every 10 years but doing your own
system then I'd base it on a much leaner figure that covers 95% of the
heating requirement from an economy and more importantly an aesthetical
point of view. Who wants to buy a house with the biggest radiators in
the world dominating every room? Screams of expensive house to heat
with very ugly rooms to the future buyer.

IMO of course IANAPP