Is a Baxi 105he big enough for my house/any good?!

Wayne100_2

Hello all, firstly I am a 'boiler novice', so bear with me! I have recently bought a four bed, two-bathroomed house. It has 13 radiators, en-suite and main bathroom. The conventional, 'tanked' heating system has pretty much kicked the bucket (It's 21 years old!). I was 'advised' by a plumber/family member to buy a Baxi 105he condensing combi, as it is a good, mid-range boiler. I have bought one, but 'plumber/family member' has now let me down, so I will fit it myself and get a 'corgi' to connect gas and commision.

After looking into it a bit more, though, Baxi seem to have a bit of a bad name. Is this justified? Will this size boiler be OK for my needs? The water pressure seems very high in our area, we have to keep the stopcock partially closed to enable downstairs taps to work OK! (I will check pressure as soon as I have a gauge). I have not installed the boiler yet..................

Also, with regards to fitting this boiler, can anyone tell me why I have to fit a check valve and expansion vessel in the mains water feed line? Can I get away without fitting these?

Thanks, any information is much appreciated!

Cardew

Personally I wouldn't have combi boiler in a largish house. Particularly if you have an immersion tank and all the plumbing in place.

I have a convention gas CH hot water tanked system and a combi boiler in an annex.

Especially in winter Combi boilers struggle to produce enough Hot water(for baths etc as opposed to the radiators)

If you look at the spec you will find the flow rate to heat water thro' 35C and they are normally quite low. Bear in mind the input water can 5C or less in the winter.

A BG fitter told me their biggest cause of call outs in the winter is from people complaining that their combi does not produce enough hot water.(and I have read lots of similar comments on the internet) I know with mine I have to turn down the flow from the tap if I want really hot water in the winter.

Wayne100_2

OK, just to change the subject a bit, can someone explain to me how a un-vented system works, and give me a rough idea of system sizes/cost, based on the info I gave above. Also, if I did go the combi route, what size would be adequate?