On Thu, 24 Feb 2005 01:13:06 -0800, Martyn Pollard wrote:

Other boilers with built-in weather compensation are; ATAG Blue Angel
(shr-24), ATAG Premier and Viessmann Vitodens 100/200. Build quality
from these two manufacturers is excellent and are well worth a look if
you are still keeping your options open. Cost is going to be similar to
C40.

The ATAG works slightly differently to most boilers(esp kestons) in
that it 'modulates up' rather than power on at full whack then try to
slam the brakes on to match the load.

This is not my understanding of how the Keston (C40) works. It ignites at
about at a gas rate in excess of the minimum (say about 25% up the
modulation range). It then operates at this moderate rate for about 30s or
so 'testing the water' then ramps up to the required setting. It does not
IME just go to 'full whack'.

My other comments a

High powered boilers are unduly expensive presumably due to
lower production volumes.

The C40 is setup out of the box to work with 70C max flow temp for sub
zero outside temperatures. The consequence is that on milder days the
boiler will reduce the flow temp to the point where it has almost no
effect. This is adjustable but you need to be aware of it.



--
Ed Sirett - Property maintainer and registered gas fitter.
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