UFH layout

[Jilly]

Hi ,

 

I've asked Wunda for a quote for our extension (3 x 6m =18m2) which will have a room and a tiny shower room, so I'm thinking 2 zones and 2 thermostats will be needed. They won't give you a layout pic until you order. 

 

We left 2 free ports on the manifold ready to connect on to and will have to drill through the wall.

 

The sales person tells me that the design team is saying I need 2 zones and one thermostat, or three zones with 2 thermostats. 

 

I'm assuming the room must be too big for one zone? (Communicating with the sales person is a bit slow). Any ideas on how to get round it, bearing in mind we only have two ports left? 

 

The plumber who came to look didn't mention this.

 

Thanks!

Edited January 5, 2023 by Jilly

[JohnMo]

Looks like two loops to me (one in each room), you could put a thermostat on each loop.  Or you could just balance the loops and do a single thermostat or none if on weather compensation.

 

Doesn't fill you confidence when they state zones instead of loops.

[Jilly]

 

Oops, my mistake 😂This is what they said:

  

'I’ve spoken to the team.

 

If you want separate thermostats, it will take it to 3 loops.

 

You can only have 2 loops if they are both together on one thermostat.

 

So not sure which way you want to go ahead.'

 

I don't understand how I will be able to just warm up the bathroom, with only one thermostat... Am I missing something?

[JohnMo]

It depends on how you operate the system, if all the other loops have thermostat, the thermostat will call for heat.  The actuator will open the loop at the manifold and if the pump and boiler aren't on, start them up.

 

Another alternative is a single thermostat can control one loop or multiple loops, depending on how the actuators are wired up in the wiring centre.  

 

As I see it, you would have one loop in each room, as you only have two ports free on your manifold.  Each could have its own thermostat.

 

An alternative control, is you leave a loop on a manual valve and always open, then when anywhere else calls for heat, that loop is always heated.  No call for heat elsewhere, this loop is off also.

 

Lots of differing ways, depending on what you want. 

 

I just have a single thermostat for the whole house, that starts the pump, all loops are always open, as I run on weather compensation.

[BadgerBadger]

I think what they're saying is your larger room is too big to be just a single loop, so it needs two loops to cover the area.  But as your shower room is quite small then the second loop is able to cover both the shower and remainder of the large room.  But that's means the shower room can't be independently controlled as it shared with the main room. 

 

So if you really want the shower to be independent you'll need two loops to cover the larger room and a separate third loop for the shower.

[PeterW]

@Jilly how big are the rooms as I can’t see any dimensions .? And where is the manifold ..?

[Jilly]

12 hours ago, PeterW said:

@Jilly how big are the rooms as I can’t see any dimensions .? And where is the manifold ..?

The whole extension is 3m x 6m and the manifold is marked in small red letters in the bottom left corner of the diagram (on the other side of the wall). 

[PeterW]

So if the door is 800, that’s approx 5x3 to be heated less the shower room. At 150mm centres that is around a 95m loop (you can do 120m at a push) and then the shower room. All doable on 2 circuits @Jilly and especially if you use self balancing actuators as they will trim the flow down based on the return temp.

[Jilly]

Thank you @PeterW, I thought it must be doable 😊

[ProDave]

You have the manifold already?

 

I would not go to an UFH supplier, I would just buy another roll of pipe once you have worked out the lengths needed and just lay it.

[PeterW]

No worries - if you order from wunda get a 120m coil and a 50m coil, there will be spare on the 50, and the 120m will mean you have plenty to do the full loops. If the stud wall isn’t in place yet, and you can get down and under where the manifold is to come off the back of it then run the shower room first, feed and return across the outside door entrance, and then run the main body of the room. Serpentine would be ideal but tbh in a room that size I would run all round the outside 100mm from the wall and then run up to the shower room and back, using up the coil on the area in front of the shower room door then back to the manifold.

 

here is a Friday afternoon plan ..!!

 

 

[saveasteading]

Remember not to nail your wall sole plated down into the pipes.