ADJUSTING UFH FLOW RATES BY LOOP

[Paul Ashley]

Good morning

 

I have UFH downstairs, rads upstairs and everything driven by an Midea 12 KW ASHP with 8.8 KW PV and 10KW battery. Following advice, the system is now on and fully open using Weather Compensation not individaul room thermostats, which is what I was using before. Internal Air Temperatures are slightly higher than desired (1-1.5C) in most of the house so I will do some tweaking to the WC curve in order to get that right. However, there are a few rooms where the IAT is higher than we want it by 3C and one room where it's at least 1.5C too low. It has been suggested to me that I can make adjustments to the flow rates at the UFH manifolds in order to correct this.

 

I am looking for advice on how to do this (if it is indeed possible on my manifolds - see pic attached). I have seen videos online for how to do this but they are all manifolds with adjustable flow meters. Is it possible to do this with my setup and if so how? If not, would it be possible to add flow meters or are we talking about an expense that's probably not worth it.

 

Many thanks in advance

Pash

[ProDave]

Can you post a much closer picture of the bottom rail of that manifold?

 

Most manifolds have a flow meter for each loop where you can see, and adjust the flow rate for each loop.  But I don't see that on your manifold.

 

I am hoping if we see a closer picture of the bottom rail someone might recognise them and know a way to adjust flow rates.

[Nickfromwales]

8 hours ago, ProDave said:

Can you post a much closer picture of the bottom rail of that manifold?

 

Most manifolds have a flow meter for each loop where you can see, and adjust the flow rate for each loop.  But I don't see that on your manifold.

 

I am hoping if we see a closer picture of the bottom rail someone might recognise them and know a way to adjust flow rates.

I think those star shaped heads, on the valves where the pipes connect, are possibly hand-tightened cover caps.
 

If these are like other weird & wonderful manifolds that I’ve encountered over the years then you remove those to expose an Allen head grub screw to adjust the flow. 
 

I could be wrong, and they may simply be the tap heads used directly to open / close. 
 

Only one way to find out…….can the OP try turning one and see if it comes off? There are isolation valves on the supply (one blue tap and one chrome knob type one alongside) if you want to shut down and isolate before explorations begin. 

[JohnMo]

Here you go, a simple image search, explain how it all works and how to adjust.

 

 

ST.04.04.00 - Control Unit For Underfloor Heating System.pdf

[Paul Ashley]

Thanks all and especially JohnMo for that very helpful guide. I think I will get flow meters fitted to the manifold to make it easier to adjust everything in the future.

 

Cheers 

Pash