The Biasi Combi Boiler thread

Harry_Nemo

Ola,

First post folks! Thought I’d give some of the money saving love back to the site!
Recently our combi had its day; a Saunier Duval, 23KW, 14 year old boiler, whose efficiency I’m sure was probably around 40%! Our house is a med- sized semi with a loft conversion (4 bed, 1 bathroom, 1 shower room). Despite its age and state, the boiler happily provided heating and hot water needs for the house.
When it started playing up I started looking around for a new combi, was surprised to find so much conflicting info on the net. So as budget was a big constraining factor I started to look at the lower end of the boiler combi market. Now I have worked for several years in the domestic building game, and know pretty well how a combi boiler works. I thought I’d use this thread to share some of the factors which I considered and to keep a log of how my boiler is coming along…

First of all by snooping around the net I found out how to calculate BTU values, I figured if a 14 year old 23KW boiler can heat the home fairly well, I wouldn’t need anything bigger than the standard 24KW that are available. 45,000Btu is what was needed to heat the house, given the average 24KW outputs 80,000KW+ there was no need to get anything bigger, and burn more gas and money. Beware I would recommend doing these calculations yourselves at least just to get an idea, a friend had a 28KW boiler recommended and installed in a much smaller home than ours, The recommendations came from the heating & plumbing shop and a CORGI guy!?!

So why the Biasi? There was a lot of opinions on the brand flying around, a lot said it was crap, many said it was reliable; this indicated to me, that it was nevertheless a popular choice. I then downloaded the installation and maintenance guides looked at the schematics. It is a well laid out design, not congested quite simple, I could easily change and replace parts myself if need be. It is Rated ‘A’ for energy efficiency. The main factor being price: the Biasi (Advanced Riva 24HE) came in at £513 without VAT.
I was recommended by a heating and plumbing shop to go for a Worcester as they are more reliable, (something I saw said on the net as well) and the price difference was under a 100quid. But boiler price is not the only factor: Here s a comparison from the cheapest store I could find online to illustrate (and where I got mine from):

Worcester Greenstar Junior 24i £592
Standard Flue kit: £51.68
Mechanical Timer Switch £30.66
Including VAT the total cost of this boiler was £792.35

Things To note:

The Worcester did not have a built in timer switch, whereas the Biasi had a 7 day digital programmable one. (the digital one for the Worcester is about £50)
The Worcester, looking at its manual does not have user controlled hot water temperature which the Biasi does, This is important because rather than mix the hot water down at the tap using cold water, you can set the water temperature limit on the boiler hence saving energy. The Biasi included it’s flue kit.
Through a few CORGI guys I know and also through experience, I’ve got to know that the life of your boiler is also dependant on how it is installed and run in those very first precious moments of its life…more on this later, Having a scale inhibitor fitted and a filter on the central heating circuit also helps. The scale inhibitor on the incoming cold water helps protect the heat exchanger, and the filter on the central heating circuit, keeps iron oxide debris (sludge) out of the boiler, both are quite easy to fit.
So this is what I got finally:

Biasi Riva Advanced HE24S condensing boiler: £513
(includes standard flue kit)
Scalemaster Platinium Scale inhibitor £35
Magnaclean Professional £80
Including VAT & delivery the total was: £745

The magna clean is basically a jar type object which connects to the heating pipe work, you can isolate it, open it by unscrewing its lid, inside is a big magnet which catches all the crap floating in the system, which can be wiped or washed clean. Although y-strainers should be fitted on all inlets, I didn’t think they offered substantial protection for the boiler.

Some guys recommend doing a ‘powerflush’ before installing a new boiler this basically pushes around water in the system at high pressure to get the sludge out of the radiators, you can hire these from HSS for around 60 quid+ and DIY, if your competent, personally I was out of time, and couldn’t afford to pay someone else to do it, but if you have the spare cash I would recommend it.

I got a CORGI friend to install the boiler at ‘mates rates’, Had the scale master put in on the boilers cold inlet only, and had the magnaclean installed on the return pipe of the heating so it would catch any debris before the water went back into the boiler.
During the install I made sure my Corgi friend did the following(although I'm sure he does anyway)!:

Flushed the system with the old boiler still in.
Filled it and flushed it again.
Install the new boiler.
Fill and flush the system twice more! (without firing the boiler)
Filled the system and added a litre of X300 universal cleaner(£10 tops folks).
Fired the boiler got it to operating temperature, then flushed the system.
Filled, ran the boiler and, flushed it 2 more times, each time cleaning the magnaclean too.
Finally filling it for the last time and adding X100 scale inhibitor (£10 again).

Each time we flushed the system I was amazed at how much the magnaclean collected in terms of iron oxide, and was thinking that this crap would have gone through the boiler and started clogging it up! You should also keep an eye on your CORGI guy and make sure he cold flushes the system at least once before firing it up, this is standard practice for the CORGI registered, but watch out for anyone cutting corners, also make sure they flush the system a few times and add the correct inhibitors! On the Boiler installation manual it was recommended to flush the system 4 times, to get all the crap out!

As I was helping my friend install the boiler, I could say it is quite easy to install with the exception of one problem, the boilers pipe fittings are designed so the pipes are recessed into the wall, we got around this by getting fitting from the local plumbing shop with 90degree bends so we could surface mount the pipes. The fittings cost an extra £15.

The boilers been in for 2 weeks, I isolated and cleaned the magnaclean one more time, although there wasn’t much sludge on it this time around. It’s fairly quiet. There is one minor niggle although I have the hot water temp to what I need it at so I don’t use the cold water when having a shower, when firing up the boiler needs to heat up its heat element, so for the first minute or two the water is quite hot, but after that it stabilises itself, to the set temperature.
I hope this post was informative, I shall keep the thread updated with any boiler happenings, services, and post the savings when the next gas bill comes in!