advice please - selfbuild

[garbro]

Hi, my 1st post so be kind!
we are starting a self build in early 2009 and would like some advice on what type hot water system to put in?,
it's a 4 bed house with 4 bathrooms and underfloor heating on 3 floors,
which boiler should we use? - someone recomended a worcster bosch greenstar 30 or 40 and then someone else recomeneded a remeha avanta 30s would you use any of these 2?
and then we need a cylinder a big one apparantly about 250lts again someone mentioned a heatra sadria?,
i'm going to put lay the pipes down for the ufh myself and get a corgi man in to fit the boiler and plumb it up to the manifolds, i like the look of the polypipe ufh system, as anyone else got a preferance on ufh systems?
thanks in advance
Gary,
ps. anyone wanting the job just let me know!

 

[Mike Jackson]

Cylinder wise I would be looking at unvented, possibly with a secondary circulation as there are 4 bathrooms. I would also look into solar for the hot water. As it's a new build you may have to do this anyway to comply with the building regs.

Without doing proper sizing calcs it's not possible to size a boiler.

Mike

 

[dontknowitall]

Boiler Calculator

(My first post!)

The link above will help you find the right size boiler. Cut your house up into cuboids (that is two cuboids if it's an "L" shaped house) and add the results together.

Although it's quite accurate don't use this as gospel - use common sense as well.

Perhaps you could get two heating orientated plumbers in to give you a quote. As part of the quote, they should suggest which boiler and why.

 

[Avatar]

Alpha do a system called flow smart where you dont need a unvented cylinder, for houses your size.
Google it and check it out.

 

[garbro]

thanks guys, very helpfull
gary

 

[stevetheplumber]

I would also check out vailants range i belive they do one with dual stats so you can run underfloor at lower temps in my opinion theres nothing as good as vailant there easy to install easy to repair and the diagnostics are second to none one model can even be linked by phone to vailants for monitoring of faults

 

[Deleted member 2053]

Who is designing the underfloor? They will be able to provide the heat requirement from the boiler. Using a decent thermal store will get over problems with boiler temperature and will also provide mains pressure hot water as you run the hot water from the top section and underfloor from the lower part. Use one of these with a system boiler like the Vaillant ecotec plus 630 (assuming that is sufficient) and it is an easy install. Also, contrary to some of the stuff you read on forums you don't need a pressurised hot water ticket to install them. If you go this route then source a unit that uses a shunt pump for the hot water heat exchanger.

 

[garbro]

thanks fellas for your advice,
had a guy out the other day says a aqua flow smart is the way to go as it would be more economical than a 300lt store, and a system boiler, as any one got any comments on the aqua flow smart? good or bad would be very helpful,
please can someone explain what is an:-
unvented system
vented system
non pressurised system
pressurised system
are these 4 different systems?

thanks again
Gary
btw, polypipe designed the underfloor systembut has JG speedfit out the other day, which would you choose and why?

 

[dontknowitall]

Try this link:

[DLMURL="http://www.as-services.net/Services/Installations.Asp"]Central Heating Installation[/DLMURL]

Pretty diagrams and short explanations - just my style!

 

[unguided1]

if your interested in going green, try an air source unvented hot water cylinder takes waste heat from the loft and turns it into hot water.

 

[Avatar]

Alpha FlowSmart

Upto 4 bathrooms supplied, 52% gas saving, no unvented system or pipework to hassle with . . .

Sounds too good to be true . . .