Pump control to thermostat wiring

[jbatexning]

Hi
Installing single zone ufl with Grundfos pump/mixing valve and heatmiser thermostat - not crystal clear from the diagrams how the control connection to LR/LS should be wired (i.e. red on the pump control diagram)

Any advice much appreciated!

 

[Deleted member 120897]

It states on the instrucions, that LS/LR (A1 and A2) go to the boiler? Are you wiring it differently?

 

[jbatexning]

Yes - installing this single room underfloor heating kit


Which replaces the radiator in a single room
I am assuming that the thermostat should control the Grundfos pump/mixing valve for the room, independent of the boiler

 

[jbatexning]

was unable to use a link in the post - the link was to thefloorheatingwarehouse.co.uk for item
single-room-warm-water-underfloor-heating-system - 12sqm

 

[jbatexning]

thefloorheatingwarehouse.co.uk/product/12-0m%c2%b2-single-room-warm-water-underfloor-heating-system

 

[Deleted member 120897]

At a guess I’d say the wiring must connect back to the boiler to operate the heating independently, or possibly using a motorised valve.

 

[Deleted member 120897]

Looking at the instructions, if you’re replacing a radiator, the ufh is controlled via a trv, not a room stat. The other option mentions a zone valve (motor valve).

 

[Basher]

Hi jbatexning
If you are just asking about the connections between the stat and the supplied junction box:
(obviously you provide wiring from the fused spur as illustrated bottom right, and then
Blue (N) to stat terminal (N) !
Black (L) to stat terminal (L) and link to stat terminal (A2)
Red (SL) to stat terminal (A1)
Grn/yel (E) insulate safely at stat, unless there is a E terminal in the stat, in which case connect it there!

If you buy 3 core plus earth cable to connect the stat, it will likely be: Brown, Grey, Black & bare copper (in cable), or green/yellow (flex)
In which case typical use of these colours is
Brown - permanent live
Black - switched live (put a brown sleeve on it)
Grey - neutral (put a blue sleeve on it)
green/yel - earth of course.

 

[jbatexning]

ChrisB1982 - It is option 2 that I am installing (own pump, blending valve, and room stat)

Basher – it was the A1 and A2 connections I was unsure about, and understand now :
live link L to A2, and red LS to A1

Many thanks for your help!