Underfloor heating problems

[Tag]

Hi 

I am having problems with my undefloor heating which is taking over 4 hours to get to temperature.one room is very cold but rest do warm up after having it on for a long period.

some area are patchy aswell.

 

thanks

[PeterW]

Welcome 

 

Probably need a bit more info to give you some help

 

Boiler type..?

 

What controls ..?

 

Make or manufacturer ..?

 

How old is the property / install..?

 

[joe90]

UFH takes a lot longer to heat up compared to radiators, mine takes many hours to heat up but I try to run mine 24/7 at a constant temp as this works best IMO. sounds like it needs balancing at the manifold (controlling water flow through different loops). Can you post a pic of the manifold so we know what you have ?.

 

edit, and the info @PeterW says above 

Edited December 7, 2020 by joe90

[newhome]

3 hours ago, joe90 said:

UFH takes a lot longer to heat up compared to radiators, mine takes many hours to heat up but I try to run mine 24/7 at a constant temp as this works best IMO.

It does, but it also takes longer to lose heat too IME. I only run mine for about an hour and a half each day (early morning) to get it up to temperature again and that works fine. The temperature drops very little during the day so I don’t notice a small temperature change. If I’ve been away and the system has been switched off for quite a few days then yes it takes several hours to heat up. 

[Mitch]

We had a problem with our UFH a few years ago of a similar ilk. 

Note: The clue for us was that all the 4 zones were taking an age to heat up from the single manifold.

 

We did a couple of things:

1. Contact the supplier - they confirmed that a batch of thermostatic valves were declared defective so we got a free replacement.  So we replaced it which was fairly straight forward.

2. When removing the valve I noticed metal fines from our radiator 'rings' were present on the filter mesh of the defunct valve, so as a precautionary measure I also plumbed in a magnetic filter to catch any future fines - as well as the obligatory inhibitor into the system.

 

Our UFH system has worked fine for the last 7 years since this work.

 

It's worth mentioning that if the valve is clogged or knackered then consider also replacing the manifold pump too but you can gauge whether you need to do this by seeing how quickly (or slowly) your system heats up.

 

NOTE - My UFH was built on 100mm insulation board and 50mm screed and laminate flooring.