"Andy Hall" wrote in message news:47701fb5@qaanaaq...
On 2007-12-24 20:00:40 +0000, fred said:

In article , Ed Sirett
writes
On Sun, 23 Dec 2007 19:10:40 +0000, fred wrote:

Andy had me worried there for a minute but it looks like they have
introduced the Qudos 28 as a mid level domestic replacement that fixes
some of the original issues I had with the Celsius 25. There are
separate control temperatures depending on the demand source with
thermistor sensor modulated control of DHW temp and they promise
compatibility with low grade heat from solar panels in the future. Full
list is: Room Compensation, Weather Compensation, Solar Control,
Modulating DHW Reheat, Solar Thermal, Analog Demand (0-10VDC), External
Lockout Signal, Remote Fascia Panel plus LCD control panel and display
of system params (flue temp, flow/return temp, other temp densors) in
installer mode. They've retained the 20m/50mm maximum flue length and
even extended it to 60m when increased to 65mm. Suffix H is heat only
without pump or expansion vessel, suffix S is a system unit with those
parts incorporated.

£722.08 and £788.13 inc vat for the 'H' & 'S' respectively at
discountedheating.

I'm quietly impressed.

This boiler would have the most sophosticated controls of any in that
price bracket.

The sophistication and the solar hook makes it attractive to the
specialist market and the techies here but I do wonder whether it will
make it in the mainstream market, it's just too clever. I hope that they
and it make it, at last a company who listen.

You don't have to use the clever bits.

It will work with just a simple switched live for the followers of Ned
Ludd.

I doubt whether many people would use it domestically with more than a
thermostat and the weather compensator.

Matt, I fo fear that.

The smart move would be to include the sensor for that in the package
because it's a very low cost item (basically a two wire semiconductor in a
weatherproof box).

It may be interesting for small commercial installations involving
multiple boilers controlled by an analogue or Opentherm controller.

Whether it makes it in the market will depend on the number of puffy
anoraks for Plumbcenter counter staff and lunches for their managers.

The ideal setup for this boiler (the Keston C36 combi is the same boiler
with a water section added) is to have the outside weather compensator
fitted (cost about £22). The DHW cylinder sensor (not sure of price) and
the Opentherm standard room temp controller/programmer/optimiser fitted
(Keston use the Honeywell Chronotherm, which can be bought a lot cheaper
elsewhere rather than the £133 Keston ask for it). Then this is a
substantial setup and at a price people can afford. Anyone can do that,
just as simple as rigging up crap stats.

The C38 combi can have the outside temp sensor fitted and the Chronotherm
optimiser programmer too. DHW is not an issue as it is a combi. Then for
what you get and pay this is also well priced. Keston have to offer
advanced control interfaces to five the boiler a hedge. Broag also sell a
well priced boiler offering similar specs using tried and tested parts too.

I have heard no bad reports on the Qudos range....yet. The Celsius turned
me away from Keston after making some super simple and reliable boilers
previously. It should be fine using parts from other boilers in the range.