Underfloor Heating problem

[BMW]

I have a problem with some underfloor heating can anyone help? Was called to a job as the underfloor heating had stopped. It appears the controller is showing the temp as 33.2 degrees and will not move down to bring the heating on. The controller upper limit is 35 degree when you set it to this it comes on but, soon switches off as it thinks it has reached the correct temp. The controller has a indicator to say if the probe is faulty and it's not lit. It's under guarantee but the company will not send anything out until I can confirm what's at fault. Don't have much experience of these but think it's either the probe or controller. I can test the probe however don't have any paper work so don't know what the Resistance should be.
Has anyone any suggestions?

Cheers

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[Deleted member 9648]

Ask the manufacturers or check online what the probe resistance should be...and then check with a multimeter.

 

[SYKRAPS]

If the controller is telling you that the probe is faulty the manufacturer should recognise this surely?

Taking the floor up could be a nightmare to get at the probe.

 

[leonard]

If the controller is telling you that the probe is faulty the manufacturer should recognise this surely?

Taking the floor up could be a nightmare to get at the probe.

You do not need to pull the floor to replace the thermostat because is on flexi conduit is easy to pull it out ,but the problem I think is that the thermostat tip must be just under the heating element .
Pull it a couple inches and try again.

 

[SYKRAPS]

You do not need to pull the floor to replace the thermostat because is on flexi conduit is easy to pull it out ,but the problem I think is that the thermostat tip must be just under the heating element .
Pull it a couple inches and try again.

If this is the case it would never have worked properly, and the tip of the probe should be beyond the end of the flexi conduit shouldn't it?

 

[BillyTheSparks]

Hopefully attached is a photo of typical readings of a probe, I think the info was from heatmat, but not too sure now.
Hope this helps

 

[BillyTheSparks]

Actually it may have been warm-up

 

[Octopus]

Did you check the resistance of the matt? Does the client know what rating and size the matt is?

Sounds to me that you need to demonstrate that the matt is or should work and then send the controller back. They may want to invoice you for the new one so pass this cost on to the client, or better still get them to arrange it.

 

[BMW]

Many thanks for all your comments. just one point the indicator on the controller did not light so it thinks the probe is ok. I think SYkraps got it the wrong way round which makes me think it's the controller?

 

[BMW]

That's great just one thing I dont know what the temp is as its not working. Controller showing 32 degree but as it's been off day's that cannot be right. Do I use the general room temp?

Bruce

 

[leonard]

If this is the case it would never have worked properly, and the tip of the probe should be beyond the end of the flexi conduit shouldn't it?

No .The tip of the probe should be inside the flexi conduit so its easy to chainge and the end of the flexi conduit should be blocked with tape to stop the tile adhesive to get inside .