Thermostat for radiant floor mat
I’m all set to start installation of a new bath floor with a small (2×5 ft) electric radiant floor mat. The installation manual says I need a “Floor-sensing thermostat”. Of course I think it’s because they want me to buy one of there’s. I had planed to use the thermostat that was there. It controlled a 3 ft long electric base board.
Do I need to have an “in the floor”(under the tile) sensor. Or can I use the one I have?
I never used the heater that was there…I just want to take the chill out of the floor, so I won’t be heating the room with it.
I also really don’t want to wait for the sensor to be shipped.
Thanks
Ward
Replies
I don't know for certain, but I suspect you should follow the manufacturer's directions. If the (only) thermostat controlling the in-floor heat was on the wall, a small mat like that would have to run full out for a long time to put much heat into the room. It's only meant for taking the chill off the floor. Without the thermostat in the floor as called for you might get the floor quite hot trying to get the thermostat on the wall to warm up.
Also, I think the thermostat for electric baseboard heat is a full line voltage type, which might not even work properly with your system.
Unless someone trustworthy is certain you can do without it, I would follow the manufacturer's instructions.
you need the in-floor unit from the manufacturer measures and cycles heat by floor temp, not ambient air temp in room been on jobs where floor unit was there but installers strung it up the wall or forgot to bury it and it later wound up on the wall.... heat mat won't work follow the instructions for mud beds/scratch coats too
Thank guys...guess I will buy a thermostat sensor
Ward
I just finished installing a 3 ft x 10 ft Suntouch radiant mat in a bathroom under limestone tile. The HO loves it. Yes, you need the in-floor t-stat because it measures the temp of the floor, not the air. I bought the programmable one from Suntouch...works well...multi-day programming, and it's supposed to be intelligent (unlike my helper)...so that if you want the floor to be 80 degrees at 6 am, it figures out the rate of rise and comes on early enough to actually be 80 at 6.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
I was about to go with Suntouch, but these things are never easy....
Can anyone provide a comparison between Suntouch and some of its competitors? For example I found this web site for a product WarmlyYours that claims to be superior to Suntouch in some ways:
http://www.warmlyyours.com/homeowner/wyuniversity/comparisons.aspx
Does anyone know of other alternatives I should be looking at? Since I plan to install DIY, ease of installation is a particular concern for me.
Am I correct in understanding that Suntouch has gone through at least two company name changes (Bask and Watts before this)? What is that all about?
Some of what that site says is correct. But I disagree on the wire spacing. If I read the drawings right, Warmly has a wire every 2 inches and Suntouch has a wire every 1-3/8 inches.
The Suntouch wire is a little stiff and thick...about like a #12 insulated solid wire pulled out of a romex cable. The power lead is a little thicker, but I planned the installation so that it was concealed by the wood base. I have only installed that one heating mat, and I thought it went down fairly easily. I would not hesitate to install another one.
Warmly notes that their biggest customer is Home Depot...how does that make you feel? I had to take delivery of my mat from a local tile dealer, bnut I talked directly with the factory in Missouri when I ordered it.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
Edited 5/20/2004 6:25 pm ET by Ed Hilton
My reading is that SunTouch is advertising zero EMF because of twin wire. Warmly says that just makes it harder to install and the EMF is minimal (the figure for EMF from vacuum cleaners was interesting). I'm a little cagey about installation; my parents-in-law had a contractor put radiant floor heat in all wrong, wires sticking up, they then had to have an installer out to fix it up. But paying someone $1K to do something that looks conceptually straightforward, on a stretched budget... But having met an epidemiologist who claims they were fired because of the results they were getting on effects of EMF from microwaves, WLAN, etc....
As for HD, I think they sell Suntouch as well. Clearly I need to keep looking :-)
The mat I am using is Sun touch. I am happy with it so far.
The intructions are straight forward and have been backed up by every one here (termostat).
The suntouch wire is heavery then others and the mat itself had less bend then the others I checked. I think it will help at install time. I have rolled it out and it stays put! no rolling back up. laid flat. I think I can get some thinset on that with out to much trouble.
Ward
I rolled out the mat and stuck it down in several places with small pieces of duct tape, then I troweled on a thin layer of quickset thinset...almost enough to cover the wires...that made it lay down tight to the slab, and presented a more flat & even surface for the regular thinset.
I was very worried about dinging the wire and damaging it, and I checked the resistance with a digital ohm meter several times, but there was no change at all.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
What are the implications of waterproof membranes for underfloor radiant heat? Putting something like 30-mil CPE right underneath a heated cable doesn't sound like a great combination. This might be mitigated if one is using some kind of trowel-applied membrane in the joints between backer boards, but there will still be some intersection between the wire and the membrane.
Don't know if this answers your question, but it might start you thinking... SunTouch says their mat can be installed under most anything, including carpet and wood flloring, with the proper preparation. So if it can be laid under capet, it can probably be laid on top of a membrane. Check the installation procedures. I just skimmed them because my install was between concrete and tile, but I think they recommend a layer of thinset or self-leveling compound with carpet & wood.
I like Bob Dylan's easy Heat method, and might try that next time. just a spool of cable that is stuck to the floor in a pattern. I had to cut the mat and adjust the layout of the Sun Touch, which was not hard to do, but it would be just as easy to lay plaing cable.
Whenever you are asked if you can do a job, tell'em "Certainly, I can!" Then get busy and find out how to do it. T. Roosevelt
Edited 5/31/2004 6:05 pm ET by Ed Hilton
FYI there is quite a lot of discussion about under-floor radiant heat here:
http://johnbridge.com/vbulletin/forumdisplay.php?s=&forumid=1
I use Easy Heat. No mat, just heating cable, and a strip-clip arrangement to fix it to the floor where the loops do their turns. They sell a programmable t-stat like their competitors, and like everyone, the t-stat reads the temp at the floor.
None of these things, a cable array on the floor, or a mat with the cable woven or glued to it, are easy to tile over. My tile guy likes to float a complete level of thinset over the cable first, before tiling, so as to eliminate bumps and waves.
Remember, when you do your layout, just heat the floor where things are open, and feet might fall. Don't go under vanities or other types of cabs, and at the toilet, you only need to go as far back as your feet might go.