UFH - Pumps, blending valves and controls

[Conor]

Probably should have posted this a few months ago....

 

I never got a proper UFH design done (just my own in loopCAD). We have the UFH laid and second fixes starting. Summary:

1. Three floors. 8 port manifold on each floor. Each manifold acts as a zone. NO control system bought yet.

2. Wired points for thermostats on basement and ground floor only (UFH on top floor was a last second addition, would be using a wireless stat)

3. No power or control cables at the manifold locations (can be added if needed and wired back to plant room)

 

My intention was to have the blending valves, pumps and actuators all located in the pump room as I didn't see the need to have a multi zone system

My plumber has pointed out that I will need a pump, valve, controls etc located at the first floor manifold due to the height above the plant room (6m).

 

Is this correct? Or is there a pump(s) that can supply the manifolds from the plant room? I'm guessing I'd need at least a 10m head pump?

 

[dpmiller]

same temp to all three floors?

[Conor]

1 minute ago, dpmiller said:

same temp to all three floors?

Flow temp or zone set temp?. Each floor to act as it's own controlled zone. Stat locations in basement bedroom, ground floor hallway and a roaming stat for first floor . Flow temp is modelled at 28c to all zones. Really want to keep all the stuff on the plant room if possible.

Edited December 8, 2021 by Conor

[ProDave]

You will NEED power to each manifold as they each contain a circulating pump.

 

It would be best if the feed to each manifold came from a central location so they can be turned on and off by a central heating time clock, possibly (as I have done) allowing different time settings for each floor.

 

How is it plumbed?  From the heat source you will want a motorised valve feeding each manifold.  I like to put the motorised valve next to the manifold, but wherever it is, that is where the thermostat needs to connect to, so the thermostat can open and close the motorised valve and turn on and off the manifold pump.

 

The call for heat contacts from each motorised valve will need to connect to the heat source to call for heat when any manifold is operating.

 

you have some wiring to do.

[Conor]

1 hour ago, ProDave said:

You will NEED power to each manifold as they each contain a circulating pump.

 

It would be best if the feed to each manifold came from a central location so they can be turned on and off by a central heating time clock, possibly (as I have done) allowing different time settings for each floor.

 

How is it plumbed?  From the heat source you will want a motorised valve feeding each manifold.  I like to put the motorised valve next to the manifold, but wherever it is, that is where the thermostat needs to connect to, so the thermostat can open and close the motorised valve and turn on and off the manifold pump.

 

The call for heat contacts from each motorised valve will need to connect to the heat source to call for heat when any manifold is operating.

 

you have some wiring to do.

 

1. Was hoping the circulation pumps for each manifold could be in the palnt room and pump via the 22mm flow and return pipes to each one.  I should be able to bring pwer and data to them if needed.

 

2. Yes, planning on the controls all coming from a unit in plant room 

 

3. Nothing in plumbed in yet.. I've a 9kW CoolEnergy ASHP with pre-plumbed tank, carell control centre and 60l buffer tank. 

 

4. Think I'll speak to CoolEnergy about this.

[PeterW]

@Conor you can do what you want to do but with some extra points to make. 
 

- insulate the flow and return on all pipes to and from the manifolds. 
- fit NRVs on the returns and also fit the pump on the return leg where possible. 
-  TMVs need to have full flow available from the heat source, suggest 28mm min 

- fit flow meters on the flow to the overall manifold to balance per manifold. 
- fit decent pumps ..! The head comment from the plumber isn’t entirely correct as these are circulation pumps and they rely on the flow of water in a circuit and the falling water coming from the manifold will assist but if you were really desperate you could put a pair on the highest manifold (one flow and one return)