Powermax 155 boiler

[robh2]

I currently have a Powermax 155 boiler that runs my domestic CH and HW system I am in the process of having an extension built and need to know if the boiler needs replacing to cope with the extra volume? My current square footage is about 700 and will be increasing to 1400.... On 2 floors.
Secondly I would like the heating in the new part to be 'underfloor' the current part of the house is radiator heated.. Is this possible to do with the mentioned system?
Thanks in advance...

 

[Agile]

The boiler will have no problem coping with a bit more heating output. If suitable controls are used an underfloor system should be possible although you need to be advised properly as hybrid systems can give rise to some difficulties due to the different heating characteristics.

Assuming its open vented at present the header tank will need to be raised well above the highest part of the system.

I dont see why the underfloor should not work but its unusual to have underfloor on an open vented system.

Tony