"fred" wrote in message ...

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.

The C55 (55 kW) is £1821. Two Qudos 28 kW boilers is £1576. ...and a back
up boiler in case. With the right boioper sequence controller this will
modulate from about 6kW to £56 kW.