5 Min. Read

Troubleshooting the Most Common Floor-Heating Issues

Ohmmeter reading

As electric floor heating continues to get easier to use and install, it’s gaining more and more in popularity. Systems are increasingly integrating with smart thermostats and home automation systems, making them easy and convenient to use. And new membranes are making installation faster, easier and more functional than ever. For instance, WarmlyYours offers its Prodeso Installation Membrane, which uses square-shaped reliefs to properly space the heating cable and hold it in place. It allows installation of both the floor-heating system and flooring to be completed in the same day. Plus, the membrane itself doubles as an uncoupling and crack isolation membrane, and — with the right accessories — can even be waterproofed. Advances like these are leading more and more people to invest in floor-heating systems.

However, the more people that install electric floor-heating systems, the more the industry learns about the common installation problems they face. That’s why the National Tile Contractors Association (NTCA) focused part of its 2016/2017 NTCA Reference Manual on troubleshooting radiant heat issues for tile and stone installations (troubleshooting is the process of identifying the cause of an issue and then solving it). Below are a few of the most frequent issues faced by installers along with ways to prevent or solve them.

Using a digital ohmmeter throughout the installation process will ensure the heating cable stays in good working order.

Issue 1: The heating system will not turn on.

One of the most frustrating things an installer can face is completing a floor-heating installation and experiencing a failure in the system. This typically happens because the heating cable has been nicked or damaged at some point during the installation process.

Solution: Use testing devices and a repair kit.

To prevent causing damage to the heating cable, installers should use both a digital ohmmeter and Circuit Check throughout the process to ensure that the cable remains in good working order. The installation manual provides details on when and how to do this properly.

If the damage has already been done, the only solution to this problem is to find and fix the break in the cable. WarmlyYours offers a splice/repair kit online. A professional can use a thermal camera to locate the break so that only part of the flooring needs to be removed to fix the problem.

Verify the capacity of your electrical panel before you begin installing your floor-heating system.

Issue 2: The thermostat is overheating.

A scary issue to run into after installation is a thermostat that overheats or even melts when the radiant heating system is turned on. This is generally caused by overloading the circuit.

Solution: Verify the voltage and square footage of the heating system before you begin.

To ensure that you don’t overload your thermostat, the first thing you should do is verify the voltage of your electric floor-heating system. The voltage should match that of your thermostat and circuit.

Secondly, you need to make sure that your circuit breaker has enough available amperage for the floor-heating system you’re trying to install. Generally, if you’re trying to heat more than 120 square feet, you’ll need a larger breaker panel and additional controls. However, if you live in an older home, you may have to upgrade your panel when heating even a small room. It all depends on the capacity of your home’s breaker box. To be safe, WarmlyYours recommends using a dedicated circuit for your floor-heating system — no matter the size of the heated area.

Finally, the issue could be as simple as loose wire nuts. If the wire nuts have not been sufficiently tightened, your thermostat could overheat. Have a licensed electrician connect your floor-heating system to your thermostat to avoid this problem.

Use your free custom installation plan from WarmlyYours to ensure proper layout.

Issue 3: Heat is being unevenly or inconsistently distributed.

If you’re noticing that some areas of the floor are warmer than others, your heating cable was likely not spaced correctly. On the other hand, if the entire floor seems colder some days than others, you’re probably dealing with a lack of insulation.

Solution: Follow your installation plan and always insulate on a slab.

WarmlyYours provides every customer with a custom installation plan that shows how the heating element should be laid out to ensure proper spacing and even heat coverage. By following your plan, you can count on having evenly distributed heat throughout the electric.

If you’re heating on a concrete slab, you should be sure to use a cork or synthetic cork floor underlayment to prevent the slab from stealing your heat. By placing a layer of underlayment between the slab and your radiant heating system, the heat generated will travel upward through the floor (as planned) instead of downward into the slab.

Using a Prodeso Installation Membrane allows you
to start up your radiant heating system earlier.

Issue 4: The grout is weak.

If you’re positive you mixed and installed your grout correctly, you might be baffled when you notice powdery or weak grout lines after installation. The main reason for this happening is that the material was not given enough time to cure.

Solution: Allow enough time for the materials to cure.

In general, do not plan to turn on your radiant heating system for at least 7 days after installation. The grout, thinset or self-leveling cement needs time to cure before being exposed to significant heat. The exception is using a Prodeso Installation Membrane. This membrane, which also acts a moisture barrier and as a crack isolation membrane, does not require as much time to cure because unmodified thinset is used between the membrane and the tile. Unmodified thinset has the ability to cure significantly faster than modified thinset, allowing the entire installation to be completed within a day.

Using a mechanical leveling system will prevent tile lippage.

Issue 5: There is excessive tile lippage.

If you feel the edges of any of your tiles when you’re walking, you’re experiencing excessive tile lippage. This happens when the tiles are unevenly installed.

Solution: Use enough thinset or self-leveling cement and employ a mechanical leveling system.

First, you should make sure you’re using the proper amount of thinset or self-leveling cement. This material should completely cover the radiant heating system. Consult your installation manual for the precise amount to apply.

To ensure you end up with a perfectly level tile floor, you can opt to use a mechanical leveling system like the Spin Doctor tile lippage control system. This system uses threaded spacer posts and caps to keep the edges of the tiles level with each other, resulting in zero tile lippage.

If you have other questions like "How do I know if my underfloor heating is working?," "How do you troubleshoot radiant heat?" or "How do you adjust a thermostat on a heated floor?", don't hesitate to contact our 24/7 technical support team at 1-800-875-5285 or by using this form.

Tell us About your Project Our team of Radiant Experts is ready to help! Just tell us a little about yourself and your project to get started.

Did you find this post helpful? Let us know by giving it some applause.


take off of hold status

WarmlyYours Responds...

That's a good point! You're correct that a potential issue may be the result of a thermostat being left in "hold status", which, in certain situations, can cause the system to "overwork".

Installed device does not have a brand name. I have no instructions. It has been off for years..came on suddenly but pushing buttons not much happens and there is no off option. Red lights came on upper left corner. Worried. What to do?

WarmlyYours Responds...

We're really sorry to hear that! From the details you've provided, it doesn't sound like it's probably a WarmlyYours system but we'd still love to be able to help in anyway. Give us a call at 1-800-875-5285 and our Radiant Experts can try to help troubleshoot the issue (or at the very least, point you in the direction of some good resources). One thing you can do in the meantime is to reset the breaker to reset the red light (this usually means a tripped Ground Fault) and then try to activate the heat by using the "increase" button. But giving us a call is probably the best bet.

The system works the last few years. This year, however, the heat won't come on.

WarmlyYours Responds...

We're very sorry to hear that you're having issues but we're also here to help in any way we can! The best first step is to give us a call at 1-800-875-5285 and our technical support team can try to help you identify the issue with the heating system.

I installed a 15 sq ft electric heating mat in a basement bathroom. It is a 120 volt system. The thermostat puts power (120 V) to the mat but the floor never get above 66F no matter what the target point is set at. The indicator shows full power to the mat and I verified that. I did not insulate the floor but I have a different mfg mat in my basement bath and the floor is nice and toasty. Ideas?

WarmlyYours Responds...

66 degrees is very low, so much so that the system might not be functioning correctly. The first thing you should probably check is to take a resistance reading with an Ohmmeter to see whether or not the heating elements or the thermostat might be at fault. Additionally you can check the thermostat's temperature setting to make sure that it's set to operate based on the floor's temperature and not the ambient temperature in the room. It is also possible that heating system was installed incorrectly compared to the functioning one (it could be too far below the floor's surface or the heating elements could be space too far apart) but hopefully that's not the case as there's not much that can be done short of replacing it.

So how do you check the thermostat setting to be sure it's detecting the floor's temperature & not the ambient temp?

WarmlyYours Responds...

That's a great question! Each thermostat will be different so you'll want to refer to their respective install or operation manuals but here's a quick video that will show you how to switch from ambient to floor temperature for our nSpiration Series of radiant heating thermostats: https://www.warmlyyours.com/video-media/switching-modes Hope that helps!

We typically turn the system off for the warmer months (April - Nov) and turn it back on when it gets cold. System has been working without issue for many years. Tried to turn it on a week ago or so and thermostat did not respond. Reset the GFCI that controls the circuit, everything else on the circuit works properly, no response from the thermostat. Is there a reset button, or protocol? If not, is there a recommended method to determine the issue?

WarmlyYours Responds...

Thank you very much for the question. If the thermostat has power supplied to it and it's on but you're still not getting any feedback from the thermostat then it's possible that the transformer in the thermostat has failed. If this is the case, then the thermostat will need to be replaced. If you have any questions about this, please don't hesitate to give us a call at 1-800-875-5285. Thanks again for reading!

Love our warm floors, unfortunately the unit stated to "click" every few seconds and we can't figure out what's wrong

WarmlyYours Responds...

Thank you so much for reading and for taking the time to submit a question. It's normal for a floor heating thermostat to make a clicking noise but it certainly shouldn't be making that noise every few seconds. It sounds like you might have an issue with the thermostat but it would be best to reach out to our 24/7 Tech Support Hotline at 1-800-875-5285 so they can try to help troubleshoot/diagnose the issue with you. Hope that helps!

How can I test my thermostat to see if it’s working properly? Heat is not turning off when the set temperature is reached. Could it be the temperature sensor?

WarmlyYours Responds...

Thank you so much for taking the time to reach out with this question. It's hard to say what the issue is because we'll need to know which thermostat you have but from what you've outlined, it's unlikely to be an issue with the floor sensor since it sounds like the thermostat is still displaying a temperature. It could be a failing relay or a settings issue but we'd need more information to conclusively diagnose the issue. You can call 1-800-875-5285 and speak to our 24/7 Technical Support Team to try and get to the bottom of the issue. Hope that helps!

Join the Discussion