Electric floor heat mystery

electrofelon

electrofelon

Senior Member
Location
Cherry Valley NY, Seattle, WA
Occupation
Electrician
Guy has 2 zones/circuits of electric floor heating cable. 240V, 3500 watts each. I installed the thermostats but nothing else. The cables had the squauk boxes on them with no alarms. I put in the thermostats and fired them up, tested draw which was about 3500 watts and all seemed good. They were on for probably a couple hours until I left. He calls me next morning, says BOTH t-stats are showing ground fault error. Any ideas? I haven't gotten back to do any resistance checks. Of course now I'm all paranoid I did something wrong...... I triple checked with them it was supposed to be 240, and they said sposta be 16 watts per foot and they used a thousand foot roll for each circuit, so that checks out. What if i didn't connect the temp sensor correctly and it overheated and failed? Is that a thing?
 
Do you have any of the manufacturer info on the thermostats or the floor heating cables?

Isn't there a GFCI trip test that could be giving them the error code? 424.44(E) / 424.45 (E)
 
Flooring guys screw this stuff up pretty regularly. Or the trim guy puts a nail in it. It needs to be checked every step of the way. Out of the box, when it is laid, again when it is covered, again when it gets in the conduit, again before energizing...
 
Elect117 said:
Do you have any of the manufacturer info on the thermostats or the floor heating cables?

Isn't there a GFCI trip test that could be giving them the error code? 424.44(E) / 424.45 (E)
Click to expand...
I didn't really play with the t-stats, I left that to them. What do you mean exactly? Like they hit the GFCI test button and that's why they showing GFCI fault?. I did tell them to reset the thermostat. Apparently the fault code is still there.
 
CoolWill said:
Flooring guys screw this stuff up pretty regularly. Or the trim guy puts a nail in it. It needs to be checked every step of the way. Out of the box, when it is laid, again when it is covered, again when it gets in the conduit, again before energizing...
Click to expand...
That's the purpose of keeping the tester on the cable until the t-stat is installed. It sounds like it was.
 
Last edited:
CoolWill said:
Flooring guys screw this stuff up pretty regularly. Or the trim guy puts a nail in it. It needs to be checked every step of the way. Out of the box, when it is laid, again when it is covered, again when it gets in the conduit, again before energizing...
Click to expand...
Base trim is not in. The squauk box was installed and in the entire time, of course perhaps it wasn't connected properly.
 
electrofelon said:
I didn't really play with the t-stats, I left that to them. What do you mean exactly? Like they hit the GFCI test button and that's why they showing GFCI fault?. I did tell them to reset the thermostat. Apparently the fault code is still there.
Click to expand...
Maybe they didn't reset the GFCI correctly? It seems strange the 2 separate circuits/zones have the same issue. They both worked initially.

The in-floor sensor not functioning would not cause the system to overheat and damage itself.
 
Expanding and contracting has probably caused some small initial damage to get worse. Good luck. Probably time to call the installer.
 
electrofelon said:
I didn't really play with the t-stats, I left that to them. What do you mean exactly? Like they hit the GFCI test button and that's why they showing GFCI fault?. I did tell them to reset the thermostat. Apparently the fault code is still there.
Click to expand...

Most of what I have read online has there being an error code for GFCI but possibly different reasons and a red light indicator to speak to possible causes.

I would be more inclined to verify they are properly testing the t-stat if everything was okay. Though, if the floor is cement and they are testing it now that it has cured, then the expansion/contraction could have damaged something if this is in like a cold storage or freezer.
 
Elect117 said:
Most of what I have read online has there being an error code for GFCI but possibly different reasons and a red light indicator to speak to possible causes.

I would be more inclined to verify they are properly testing the t-stat if everything was okay. Though, if the floor is cement and they are testing it now that it has cured, then the expansion/contraction could have damaged something if this is in like a cold storage or freezer.
Click to expand...
There is a chance it is user error. I did tell them to READ THRU THE INSTRUCTIONS to read about the error code, reset procedure, etc..... You know how people are tho, they probably didn't and just pushed more random buttons in random order🙄
 
You must log in or register to reply here.
Top