OT : Boilers

Not the ones at the NEC, the central heating type, sorry.

The boiler here is about 12 years old, noisy, inefficient (if I believe
the hype about condensing boilers), I've fixed a few times and to be
honest I don't believe its worth coaxing it along much longer.

Its a 4 bed detached, 1 bath, 2 showers fed directly from the hot and
cold supply, hot water tank in the airing cupboard, no cold water tank.

The hot water tank I swear is plumbed in back to front as the incoming
cold water dilutes the hot water immediately and you only get 1/2 a bath
full, or one shower. Also if the boiler heats the tank up, 2 hours after
the boilers switched off the hot water is luke warm. So that needs
ripped out and replaced with another or a direct hot water supply.


What would be the best type of boiler for me?

Plain water boiler with a replacement hot water tank?
Instant hot water / combi boiler?

Condensing or some other sort?

Will the one thats cheapest to run have some compromise like its crap at
heating the hot water or something?

Also is it worth getting it from British Gas? Will they chuck in a year
or 5 free boiler maintenance and guarantee plan or suchlike?

Actually the ideal for me would be finding someone who will fit what I
tell them to fit, plumb in the gas and do the water plumbing and leave
me to sort out the electrics.

 

Sounds like a combi might be what you need, but the drawback is the lack
of stored water supply in the event of mains loss. Also no hot water or
heating if the gas /electric fails too.
Personally, I'd stick with the existing system and get a modern boiler
as a simple replacement, but that's just me.

If it's a normal hot cylinder, there's no way it can be connected
wrongly - there's only one inlet (bottom, side) and one outlet (top).

 

Possibly best to have a look here first:
http://www.diydoctor.org.uk/projects/domestic_hot_water_systems.htm

Depends. One factor can be location. In a similar house to yours I was
advised not to for a condensing boiler because the flue is very close to
a patio window, and there was no where else to move the boiler to except
at vast expense. Even the more efficient conventional one I have now
chucks out a fair amount of steam when the air temperature is low. A
condenser would really fog up the large area of glass nearby.

A cheap one may well have a crap fan. Ours got very noisy a few weeks
ago. British Gas came and lubricated it and the problem was sorted, but
apparently the bearings may die fairly soon. In which case they assure
me they will replace it quickly for free.

Mine is still under guarantee from British Gas. I also paid up front for
5 years service at 'bulk by' rate, but total cost delayed for 12 months
IIRC. I was happy with the overall deal. Particularly given the
unforeseen installation problems which they had to address at no
additional cost to their quote.


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| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

So there's one way it can be connected wrongly.

 

Just you in the house?
A Combi would be ideal IMO.
You only pay to heat the water you use, unlike a stored water system,
where you heat up a full cylinder, then maybe do not use it.
Changing a convential system to a combi would be quite a change, witha
lot of work to change pipes, so 2 days work for 1 bloke, maybe 3.

You have no choice now, either a condensing 'stored water' type, or a
condensing combination boiler.

Cheapest to run = either more effiecient or doesnt get so hot.
Boilers are rated into A, B, and maybe some at C still. As from next
year iirc, all have to be 'A' rated, most already are, some B rated are
being sold off quite cheaply, B+Q are doing a B rated combi at £300 now.
I fitted one a few weeks ago, and though it is a little noisy compared
to our old one, it does the job well.

British Gas have, probably, the worst reputaion for supplying and fixing
boilers. Whether it is true or not, I dont know, but there rarely seems
to be good reports of them.

I know a bloke who'll do that, though he is just south of Leicester.
dead good, tells it straight, and does the job right.
I can give you his number if you cant get anyone local.
Alan.

 

'fragmented' wrote...>

<snip>

Another thing is that my radiators are an open system, header tank above
the hot water tank that tops it up when it needs it.

I see most modern boilers require pressurised systems. If I try to
convert my system to pressurised am I likely to find about 150 leaks
hiding under the floorboards? Can you get condensing boilers that work
with open CH systems?

I haven't actually seen a pressurised CH system that hasn't needed
frequent attention because the system looses pressure, are they very
problematic? (sisters, Jackies, current work, previous work)

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, fragmented

Mine has needed topping up[1] once, just after it was fitted and has run
for over a year without further attention.

[1] i.e. turn a tap, wait a sec, turn it off again.

 

'Grimly Curmudgeon' wrote...>

Only ever had one period without water, which was when I was replacing
shower/bathroom fittings.

This place is a "family home" (well, it would be if I wasn't here
IYSWIM), and the hot water can't even fill one bath.

No idea whats wrong with it, I suspected that they've taken the outlet
from the bottom, so the cold water coming in just drops straight through
the hot water cooling the whole lot down quickly.

Hmm, there's a simple test I haven't done here isn't there?

Thank.

 

'Pete Fisher' wrote...>

Will do, thanks.

Where it is now is as far from the conservatory as it can be, so I can't
see (more) steam being a problem)

Cheapest to run I meant, which most likely won't be the cheapest to buy.

But I suppose if they're all "grade A" now (or soon will be) then
running costs per KWh output should be roughly the same?

Ta.

 

Not by anyone with more than two brain cells.

 

'A.Lee' wrote...>

Mostly just me. My nephew does turn up every morning for a shower and
then dissapears off to work. (rents a room and never stays in it)

S'wot I'm thinking.

Can modern combis really deliver properly hot water at full flow mains
pressure?

I had a look at the Vallient specs and they quoted 10 mins to fill a
bath with 35 deg C water? My cold tap can fill a bath in about 2mins so
that doesn't sound like its anywhere near full mains pressure flow rate
hot water.

Also whats the flow rate for a typical shower? A proper shower, not one
of those crap dribbly cheapo electric showers!

I thought that would be the case, but with a £600 gas bill this year, I
want to try to save some of it.

(I should be looking at cuting down the lekky bill which is over twice
as much)

So cheapest to run will effectively mean less heat output and colder
house?

Ok, if they're all going to be 'A' rated I'll work it out on the heat
output I need for the house and add 15% cause I'm nesh

Heh, what I was thinking but always worth asking.

Can you email it to me, reply-to email address is valid.

Thanks.

 

'Wicked Uncle Nigel' wrote...>

So thats a thumbs up for BG and pressurised systems, ta.

When they fitted yours did they convert it from a non-pressurised system
or rip it all out and start again?

 

Condensers appear to be mandatory now in any case. I got my new boiler
just in time it seems.

Not necessarily though.

Pass, but that sounds logical.

See WUN's post. When they came to install mine they found the estimator
hadn't allowed for some sheet flooring on the landing where they thought
there would be boards (took me by surprise as well).

They also found the calorifier in the hot water cylinder was leaking in
to it. A valve had been fiddled with to compensate apparently. As they
held the service contract for the previous four years they had to agree
to replace the cylinder for no extra. That meant a new cylinder with a
very efficient sprayed on insulation jacket. It also meant a very sweary
installer who had to squeeze it in to a very tight built in cupboard off
the bathroom. The whole job took a day longer than expected. I'm not so
sure it would have been possible to get another contractor to stick to
the estimate.



--
+----------------------------------------------------------------+
| Pete Fisher at Home: |
| Voxan Roadster Gilera Nordwest * 2 Yamaha WR250Z |
| Gilera GFR * 2 Moto Morini 2C/375 Morini 350 "Forgotten Error" |
+----------------------------------------------------------------+

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, fragmented

Pretty much started from scratch. The deal included new radiators
throughout, since some of the existing ones were mis-sized, and none had
thermostatic valves. They reused most of the existing pipework.

 

It's not uncommon for older systems converted to pressurised to have
leaks - the quantity varies from 'some' to 'lots', but usually of a
small nature. Of course, if your 20 year old rads have weak corroded
bottoms, expect that go suddenly from 'tiny' to 'massive' overnight -
all over your carpets.

You can get a straight replacement for your boiler that will work with
your existing system and forego the pressurised option.

 

Our house is just a tad smaller than yours.... and we have a combi
boiler.

Hot water on demand, at mains pressure. Fills a bath no problem with
steaming hot water and doesn't go cold if someone uses a tap elsewhere
in the house.

 

Yeah, run a hot tap and touch each pipe to see which is hot!

 

We fitted a new combi boiler just before the "must have a condensing
boiler" regs came in. It's a Worcester 28SII and supplies hot water at a
good rate. I picked the fitter by looking at the Worcester website. There
was only one recommended fitter for our area and they gave me a reasonable
quote compared to SWALEC and some others picked from yell.com. It's worked
out very well. In 4 years I've seen the fitters 4 times: installation plus
3 annual services.

My fitter came to service our boiler a few days ago. Despite being a
Worcester Bosch approved installer he says he would probably install
Vaillant in his own place as their condensing boilers are the most
reliable. They are expensive, apparently.

You really need raden's view on this, to corroborate.

Fine. Much better than the 7kW Redring shower we had in the last place. We
just have a Mira mixing tap in the shower: one of those jobs that works
like a joystick. There's a pressure equalising valve on the shower input
which is very good at regulating flow if the washing machine does a rinse
cycle when you are showering. One of these jobs:
http://www.plumbworld.co.uk/pressure-equalising-valves-344-0000

 

'SteveH' wrote...>

What make and model please?

 

Big white thing with the 'Vaillant' brand on the front.

Other than that, I have no idea.