Underfloor Thermostat Question

[Stephen T]

Hi Guys
Hoping someone could take a quick look at the attached photos and advise if this is an OK setup. I've moved into a house that was built 20 years ago and has wet underfloor installed. I had a few issues at first with some of the zones getting too hot. The actuator heads on some of the zones wouldn't fully close the valves. Since they were 20 years old I changed all the heads and that solved the problem. My thoughts have now turned to the thermostat on the 3 way valve which I believe allows hot water into the loop. I'm a plumbing novice so I don't know if this is an good setup or not. There is a Danfoss Ravi thermostat head with a probe which is attached to the return manifold. I've heard underfloor should run at around 45 degrees on the flow side (Screed floors) however mine seems to be 60 degrees plus. Any advice would be greatly appreciated.

Update: I have the thermostat turned down to one which should mean it's closing around 43 degrees.

 

[SimonG]

Get an independant thermometer to make sure the two pipe thermometers are reading correctly. If they're ok then change the head and probe.

 

[Stephen T]

Get an independant thermometer to make sure the two pipe thermometers are reading correctly. If they're ok then change the head and probe.

Hi Simon, thanks for that. Is it correct that the probe is on the return manifold? It seems to me that the return is unlikely to reach a high enough temperature to ever close the thermostat. The lowest temperature it closes at is 43 degrees. Should I not be aiming for around 45 degrees on the flow manifold and around 30 on the return. So saying all that should the probe not be on the flow manifold?

As I say I’m a bit of a novice who is trying to get his head around ufh, sorry if I’m talking nonsense!

 

[Dave Marques]

You're correct 45 deg c is the optimum for a screed floor. Some manifolds will shut down at 60 degs - ish to prevent damage to flooring.