Central / ufh / pump heating question

[xactive]

Hello all, first post so take it easy on me!

Diagram attached to hopefully explain it easily. We have recently had 2 storey extension built onto existing bungalow. Bungalow houses boiler and existing rads etc. radiator circuit has been extended into new part and on the ground floor a QPL UFH conservatory pack has been spurred off it to warm conservatory (indicated as problem area on diagram), the spur to this has been taken off flow and return pipes where the circuit goes vertical into second floor of extension, when the pump for the UFH comes on it is robbing all the hot water from the vertical pipes so the extensions radiators aren't getting warm. Now my question is can I break the circuit here and have the pump feeding the new extension as well as the UFH as per my diagram or can any of you experts forseee any problems??? Thanks for your time in advance.

UFH

• xactive
• 7 Dec 2011
• 1

 

[Norcon]

A few points..

The cold branch to the blender may need a non return valve fitted.
( low resistance type)
What can happen when rads only required is the flow path can flow straight across the blender back to the primary return so your rads stay cold.
Also without a zone valve or actuaters on a manifold you might get a high temp parasitic flow through the ufh loops.
The loops need to be balanced at the manifold or fit a single valve to throttle the flow into the loop/s.

And finally the primary pump needs to operate in series with the ufh pump.

 

[xactive]

OK thanks for all your replies. Before trying what I proposed and after doing a bit of further research I balanced all the radiators and turned the pump down slightly on the UFH. I'm delighted to say it worked a treat! Once again thanks for all your replies.