Underfloor Heating Control and Wood Burner

[martin69]

We have a polypipe wet ufh system with PBPRP controller which works reasonably well, over a period of time learning how early it needs to call for heat in order to reach the comfort temp through the ITCS feature. The problem comes when we light a wood burner in the room. Despite following Polypipe's advice to turn the controller off while the stove is interfering with the heat, when we put it back on it has lost all its knowledge, so fails to fire early, and we have nearly a week of cold rooms while it relearns how early it needs to start - by which time we are lighting the stove for the weekend again!

Does anyone have any way round this, or any recommendations as to the best controller to use for max efficiency and flexibility please?

 

[Richardthe3rd]

We have a polypipe wet ufh system with PBPRP controller which works reasonably well, over a period of time learning how early it needs to call for heat in order to reach the comfort temp through the ITCS feature. The problem comes when we light a wood burner in the room. Despite following Polypipe's advice to turn the controller off while the stove is interfering with the heat, when we put it back on it has lost all its knowledge, so fails to fire early, and we have nearly a week of cold rooms while it relearns how early it needs to start - by which time we are lighting the stove for the weekend again!

Does anyone have any way round this, or any recommendations as to the best controller to use for max efficiency and flexibility please?

It really depends on the type of flooring Martin. A system in concrete can take a long time to cool down & in turn take a while to heat up. Most controls will sense the ambient temperature in the room where it's sited.
Sorry I can't appear to get any info on their web site regarding the thermostat, so if you have a link that would be helpful.

Your stove my have a very high output & your home well insulated, so there will be a good fight going on between the stove & UFH!!

 

[Agile]

You should not interrupt the mains power to the controller.

It should have a facility to turn the output off when the stove is on.

Tony

 

[Norcon]

If the stat is controlling other rooms then probably best not to have it located in the same room as a stove.

 

[chantelle]

Not familiar with controller but can you not turn underfloor heating up for that room manually like a roomstat? Surely you can?? Regardless of wood stove? Have fitted underfloor with programmer for each room and just advised customer to either use it set for temperature or override and just turn it on regardless,like any roomstat? Ask your installer to educate you on how to use the various programmers. Hope it`s not beneath you.I normally find that people who have all this hi-tech comfort installed are usually too thick to operate it but are loathe to ask the skilled engineers for fear of embarrassing themselves.

 

[martin69]

Thanks for all the replies.

Yes, you can turn the temperature up or down manually, although it is not a very easy interface. The programmer only controls that room, and turning the controller off does turn off the output. The stat is the PBPRP at www.ufch.com

The issue we have is that this controller was recommended to us by the installer as 'intelligent' because it has an ITCS feature by which it learns how far in advance of the time comfort temp is requested it needs to call for heat in order to reach that temp at that time. So, if the controller is set to comfort temp of 16 deg at 6am it will fire the boiler at 4am in order to heat the room to that temp for that time. This system generally works quite well, though it is a little blunt. The problem is, when we light the stove (usually weekends), despite Polypipe's advice to turn the controller off, all this learning is messed up, and the controller seems to take best part of a week to relearn, by which time we are ready to light the stove again! So, last benefitted from stove heat last Mon, it is now Thurs, and at 6am the temp is only 13.8 deg, with the boiler not having fired anything like early enough.

Just wondered if anyone had any experience of any other brands of controllers or similar experiences?

 

[SteveSteady]

Over two years after this thread went dormant but searching around I found it and we seem to have exactly this problem!

We have wet UFH in all rooms and a wood burner in the lounge as well. It's a Polypipe system and each room has a wired ITCS / Optimum start programmable thermostat.

We moved in to the new build house last December and had various problems. The Hall / Landing thermostat was not even plugged in so these rooms were always cold - didn't take long to figure that one out. We have concrete / tiled floors downstairs apart from in the lounge which has carpet. Carpet in all upstairs rooms. The carpeted floors never got warm even with the system on for hours - turned out the carpet fitters had fitted a really high TOG value underlay so we had a TOG of over 4.5, way above the recommended 2.5! The builder had to pay for new underlay & fitting as he'd not kept a record of what he'd ordered!

We've also had problems getting enough heat into the water cylinder using the boiler - I'll come back to that one.

So, to the wood burner and the ITCS / Optimum start learning. I think we have the same problem.
We use the wood burner every so often for fun / comfort / effect. The kitchen far away from the wood burner seems to learn when to come on ahead as do the bedrooms. The Lounge and the Hall / Landing play up as you described. Always seem to lag behind and not be warm in the mornings while the kitchen etc is.

I think the Hall / Landing is messed up as well because the thermostat is mounted on the other side of the lounge wall near the door - we rarely close the lounge door as it's not a massive lounge and a 5KW wood burner makes a sauna of the room otherwise.

So this thread was very interesting to read - as I think we have the same problem!

I've read you can turn off the ITCS / Optimum start feature. This would be good and just have the lounge / Hall thermostats set to when we want them on.

I've had a search in Polypipes thermostat instructions and they say they describe how to turn the ITCS off on page 9 but I can't find it there.
Anyone know? If not I think I'll call Polypipe and ask.
I'll report back on what they say about all this.

The hot water heating issue is perhaps for another thread!

 

[SteveSteady]

I called Polypipe tech support line.
They are nice chaps. Talked me through how to turn off the Optimum start / ITCS feature on the thermostats.
I've turned the Lounge one off and will see how it goes now I've put it on 1 hour earlier.

They did not have much of a view on optimum flow rates or pump speeds. Basically try things out and see how it goes was the advice.

 

[Agile]

Flow rates and pump speeds are not the salient feature.

Its the temperature differential which needs to be measured with a contact thermometer.

About 6 C to 12 C seems most popular.

Tony