decepticon

Im looking to fit a gas boiler in my new garage extension with 2 rads and a sink. Any recommendations for a reasonable small boiler?
£6-700 ish

500

2 Rads, it won't modulate down enough. Can you not take a feed of the existing heating and run it into the garage? you can zone it so it's not on all the time

decepticon

That was my original plan but I didn't like running the pipes outside due to frost and its quite a complicated route. Considered a thermostat and timer which would turn on for five mins every hour or two so prevent freezing and a two zone system.
Do you mean the return water will be too hot and mess up the boiler? Won't it simply switch off more? Liked the idea of running hot water too which the boiler could do.
Any other good ideas?

ALi-B

iTrader: (1)

If you wanting to heat water your probably looking at a combi. Problem is most modern combi boilers have a minimum output of around 8Kw for the central heating. SO, yeah, it'll probably cycle, so won't be that efficient. Doubt it'll overheat, but it wouldn't be ideal.

Mines not too happy running the underfloor heating on its own...its about 6Kw loading. So boiler ramps up to 88degree pretty quick and causes it to shut down and start cyling. I've managed to adjust the anti-cycling timer and target temp differential in the installer menu and set teh timer do it only runs with teh rest of the heating to help counteract this. But either way I do have circumstances with a condesing boiler that isn't condensing because its running too hot (so much for underfloor heating being efficient ).


If you forget about instantly heating hot water and just go for a system boiler, then you can have a much smaller ouput boiler: I had a quick look on teh Worcester Bosch site and the Greenstar 12i system boiler has a minimum output of 3kW which would be about that of two large double convector rads (1000mmx500mm).

It could heat a hot water tank, but I'm guessing thats overkill for a garage.

500

Run the pipes underground and put the thick Climaflex lagging on them. You can stop them freezing by having a frost stat and pipe stat so it fires the boiler and then shuts it off when the return reaches 20 degrees.

Having a boiler cycle is very bad for efficiency.

Ali, 2 words that should solve your problem if the rest of the system is sized properly. Weather compensation. You need to have the flow to be less than 55 degrees ideally for best efficiency.

The thing is, you have a Worcester. It has an aluminium heat exchanger. What does condensate do to an aluminium heat exchanger?

imprezagaz

iTrader: (2)

You could get some thermostat controlled electric wall heaters and then a under sink water heater for your hot water

ALi-B

iTrader: (1)

used to have weather compensation an aq6000. Sadly not multi zone which is required. And there is a pipe work and house layout issues that results some rooms being unacceptably cold, and makes it difficult to hydraulically separate without ripping up the entire downstairs flooring. Got a thread on this in DIY.

I used to have a glow worm energy saver 80 that lasted a less than 4yrs 3 of which it gave us Lots of grief, so am fully aware of what damage condensate does. Condensate rots steel in a matter of months - even when it's galvanised. Poor quality stainless has its issues too- especially if it's spot welded.

Tidgy

maybe look at underfloor heating?

dpb

http://www.hotukdeals.com/deals/mr-c...rs-659-2111000