Combi boilers and underfloor heating

[DaveK43]

Can someone help me please?

Hi there everyone, this is my first posting so I hope I've got the format and etiquette correct, please let me know?

I'm running 7 rads off a Vaillant EcoTec pro28 combi and I want add a single loop of underfloor heating in a 24square meter extension.

I intend to run the whole system off the boiler timer and use the thermostatic valves on the rads for temperature control and a motorised valve on the UFH loop for temperature control of the extension.

I am confused as to whether I need a secondary pump for the UFH or whether the combi pump would be ok.

I'm also not sure as to whether using a secondary pump would cause problems with the combi.

I would be greatful for any advice

 

[dcawkwell]

You will need a second pump and mixing valve.
The temperature of the heating water will be too high for underfloor.
Personally I would got for normal radiators respond fast and cheaper to install. Underfloor is grossly over rated.

 

[Tipper]

The temperature of the heating water will be too high for underfloor.

Doesn't the mixing valve take care of that?

 

[Agile]

He means UNLESS there is a mixing valve!