Help to understand UFH components

[Dedekind]

Just out of curiosity I wanted to understand what each component is doing in my system.

I have just installed a combi boiler that will heat the HW, as well as UFH in an extension and the radiators in the rest of the house.

We wanted to have two zones: one for the UFH and another one for the rest. Our builders have brought a 2-12 port manifold that has a lot of bells and whistles including one of those pumps, as well as a port 2 valve actuator. What are these things doing? I thought connecting the boiler to the manifold was enough. Why do we need another pump?

 

[rgimblett]

The pump circulates water around the underfloor heating system and when the temperature of the water coming out of the floor drops too low it adds in a bit of hot water from the boiler. FYI - I'm a lay person with an underfloor installation since 2006. Our installer made the mistake of running most of the floor from just one port. The pipe on that port is so long that the first half of the floor gets suitably hot but the water has cooled by the time it gets to the second half of the floor.

My advice is make use of the 12 ports to break down the floor area into smaller areas. The installer should know the ideal floor area for each port to handle.

The number of ports doesn't necessarily equate to the number of separate zones. You can run all ports together as one zone, or as 3 zones each having 4 ports or any combination you like.