"Mark" wrote in message
...
On Tue, 21 Jun 2005 21:14:29 GMT, Martin Evans
wrote:

o plumber 2 (who spent a considerable amount of time with me - what
patience) suggested going to a combi boiler (although he would fit a
conventional one) - in fact a Worcester Greenstar 440 floor standing
combi boiler. He said

a) at 20l/min at 35 degrees C rise, running on mains pressure (subject
to testing mains pressure which I'm given to believe is good) it was
more than sufficient to match my existing pumped shower and everything
else.

I have one of these. You only get the 20l/min for a short time, until
the internal thermal store is depleted. After that you get about 11/12
l/min (my estimate). I find it half fills a large bath before
dropping to the lower rate (you have to turn the taps down otherwise
you get cool water).

The Alpha CD50 automatically reduces the water flow, when its substantial
store is depleted. The 440 HighFlow will fill an average bath, It still
will fill a large bath quick enough as it never runs out of hot water,
filling it in with tow stages of flow rate. Also the recovery rate is very
quick; a few minutes.

e) we discussed pluming etc and the flue would be routed outside and
up the wall to above head height.

I don't know what the fuss is all about pluming. It's only water
vapour and is rapidly dispersed.

It can make a wall very wet if directed against the wall, or the prevailing
wind blows it onto the wall.

f) we discussed reliability of Worcester 440 and he said he had fitted
loads, it was good, needed to be serviced once a year and although
slightly more involved than a conventional boiler was not time
consuming or expensive. On board diagnostics would even detect a leak
in my heating system.

Really? I don't remember mine reporting anything when I had a leak.
All I noticed was air in the system and the pressure dropping.

The newer models may do. The Greenstar 440 is a very new update.

h) I mentioned past experience of combi boilers (over 12 years ago)
and he said the worcester 440 was miles ahead of whatever I had then
and I would not suffer from excessive reduced flow in winter. He did
go on quite a bit about what temperature my shower ran at and how I
was mixing alot of cold water with hot to get confortable.

In general combis are good for showers and not so good for baths.
YMMV.

DON'T GENERALISE. The 440 is a very good combi and will fill an average
bath quickly. The Japanese Rinnai multi-points will fill as fast as any
unvented cylinder system, belting out the hot water.

j) all (optional but included in his price) would be in the boiler
itself except for a room thermostat. He pointed out the problem with
having a room thermstat in the hall where the radiator had a TRV.

Just get rid of the TRV on that radiator.

k) the worcester 440 had an in built 12l (I think) vessel which had
some advantage in the speed in which hot water reached my taps - not
sure exactly.

It has a thermal store internally (that's why it's so big).

About 60 to 70 litres.

Cost £2600 (for combi boiler worcester 440 floor standing boiler,
replacement gas supply to boiler, ripping out / bypassing old system)
- sealed system.

Seems a good price. The boiler itself is very expensive.

He has to fit the condensing version. This can be fitted anywhere and has an
integral condensate pump, so there is no excuse not to fit the condensing
version. If he doesn't fit the condensing version he is breaking the law.

o on combi boilers he would do a quote for both but a combi would be
more expensive since it required ripping out a lot of stuff - somewhat
at odds with plumber 1 who said the exact opposite.

Maybe you could rip out the old stuff yourself to save some cash.

o on combi boilers and my concern over loss of output in winter and at
my main ensuite shower he said it would cope so long as someone did
not use any water elsewhere in the house (whether cold or hot). He
recommended not having a combi boiler.

I doubt that an ordinary combi would be very good at supplying two
showers at the same time.

o mains pressure was good in my area and not a worry.

Also check your mains flow rate to make sure that is OK. (16l/min).

o condensing boilers produce condensate which is slightly acidic and
has to have somewhere to drain away.

Can go in a dedicated soakaway.

The 440 has an integrated condensate pump to pump it into a drain that can
be way away.

The Greenstar condensing 440 Highflow is a good boiler and you will not be
disappointed with it.