Andy Hall wrote:
On Sun, 25 Jan 2004 18:40:38 -0000, "David Hearn"
wrote:


In terms of installation, the only additional thing for a condensing
model is to provision the condensate drain and that is trivial.

Considering that you would save 20-25% of energy costs and some
quite inexpensive condensing models can be found, to me it seems a
no-brainer to use one, even accounting for all your other
expenditures and reduced income.

But I'll already be saving fuel costs by using a new boiler compared
to a 15/20 year old one - I wouldn't get 20-25% extra by going with
condensing over standard.

The Ideal Classic SE RS has a SEDBUK efficiency of 79.9% which is low
compared to 91% for the better condensing boilers. Some condensing
ones go as low as 85-86%. SEDBUK claim that large old heavy weight
boilers (which I would say the Baxi WM 531 RS we currently have is)
is only 55% efficient. Even if it was a lightweight one it would be
only 65%. Currently we pay about £30 a month for gas I think, £360
a year (which is between SEDBUK's heavy and light weight estimates
for a semi).

Assuming currently 65%, then if we went to 100% efficiency, we'd
spend £234 a year (£126 pa saving). 90% efficiency would cost £260
(£100 pa saving), 85% cost £275 (£85 pa saving) and 80% efficiency
£292 (£68 pa saving).

So, going with a condensing boiler I would save between £85 and £100
per yead and with the Ideal Classic I save just £68. The savings
over the Ideal Classic would be about £17 to £32 a year.

Ideal Classic SE 15kW £582 inc VAT.
Ideal Icos HE 15kW £675 inc VAT.

Are you sure that the vanilla SE is still available? I can only find
price references for the fan flue version and I believe you have to
add a flue kit for that.

Yes, the standard SE RS rather than the SE FF is available still:

http://www.plumbworld.co.uk/acb/show...=5378&CATID=73

And I expect I'll need the standard RS flue kit @ £40.

Surprisingly, the fanned flue version claims 78% efficiency in the manual
whereas the balanced flue version claims 80% in the manual. Though I'm
sure there's a degree of error/variation anyway.

Thanks

David