Uponor UFH issues

[Martynrosscampbell]

Hi all

I was called out to look at a flat with new tenant who had no heating. I think it had been empty for a while prior to her moving in. I'm an electrician by the way. Plumber had already been and told the agents it was my problem!

UFH wiring centre (C-33) i think not seeming to be doing a lot no led's lit on room stats. push fit terminals on everything so difficult to get a voltage reading off anything. noticed that the external programmer's (i-35) wiring was in the wrong 2 terminals swapped them to the correct terminals and off it all went. Happy day's, nice easy call out i thought!

2 days later tenant is without heating again. The plumber had mentioned about linking out controller or something in another one in a flat in same block. I linked out the programmer terminals, everything fired up beautifully. told tenant i needed a new programmer and heating would work on constant for now just use the room stats for control! all good i thought, just need a new I-35.

2 days later (yesterday) tenant texts, she has no heat again. I have a good poke about realise that L and N are reversed on the feed in to wiring centre. shouldn't make a difference but thought i'd swap it so its correct anyway. It then fired back in to life. I told her to text me this morning and let me know if it was still on. It wasn't! I told her to try turning it off and on again to reset it. to my surprise, this worked, she's happy and can do that again if she needs heat. Now i need to work out what's wrong with it!

So my question to you is.

Whats wrong with it??

PCB in the wiring centre?
Some kind of thermal cut out operating that i can't see?

Thank you in advance!!

 

[ironsidebod]

Depending on the age of the C33 it could be suffering from relay sticking/failure - have a search on google.

There is a temperature limiter fitted on the manifold, these are usually set to 60deg C. No idea if they need a power cycle to reset or whether it will stop/allow flow as necessary.

Which manifold is it? Any pictures?

 

[Martynrosscampbell]

probably 8 or more years old i would think. just looked a bit more on google and a lot of people saying there was an issue with controllers.

No photographs of the manifold i'm afraid and didn't get any model numbers from it. It did have a grey box above on the end which i presumed was some kind of cut out or limiter as it was wired inline before the brown switched live of the zone valve. I wasn't getting a feed back out of the controller so it wasn't getting as far as that.

New Controller me thinks. Landlord will be chuffed!!

 

[ironsidebod]

The grey box you describe sounds like the thermo cut out, over on the right hand side above the pump?

Does sound like the controller - not mega expensive but not exactly cheap either!

 

[Underfloor Guy]

Did you ever get this sorted, it is a common problem that they are not installed properly. DO NOT link out the timer output this is a digital output and will not work.
The first thing to check is that the channels are full from the left hand side with no gaps between then actuator outputs.

 

[Martynrosscampbell]

Yes, just got this (and the flat below) completed in the last few weeks. There was nothing wrong with the wiring as far as I could tell. Uponor's technical advisor told me I would need to replace the controller but they no longer make it. The equivalent would also mean upgrading the room stats. It was nearly £400 in parts, plus my extortionate labour charge!! I did some searching online and found a company on eBay offering a repair. Sent it off at a cost of about £35 plus PandP. A week later it was returned and fitted. All fired up as it should. So far no calls to tell me otherwise! A result I would say. There is 16 flats all the same so I imagine I will have to repair a few of them in the coming years!