Anyone familiar with radiant floor heat?

[savanna]

Im looking for some advice here. We finally got our 28x36ft cabin built. It is 1hr from my house where I work and live which is in the southern tier of WNY. We went with a frost wall and concrete pad with pex in the concrete for a radiant floor heat system. For extra free heat (from my woods) when we're there a nice wood stove was also installed. The dual purpose boiler we had installed is a Dunkirk and it will run the floors and the cabin hot water with propane fuel source. Before we have this fired up im looking for some opinions on my system.

Question: My contractor is not recommending Glycol in the lines as he states it can reduce the efficiency and it is also corrosive to the system. He says I should get some kind of power out alarm or a freeze alarm to indicate the boiler isnt working and the temp has fallen below a certain temp. Right now I dont have any kind of WiFi or anything so what system is going to notify me and how? The temps here in the Buffalo area get cold, like into the single digits but usually not that drastic or for that long a period. Winter here is usually in the 20's and 30' with spouts up and down a bit. I sure as hell dont want these lines to burst or anything. Even after hunting season is over I will be going up there on a regular basis, probably once a week. Now that I will have heat and running water we can use it a lot more.

Does anyone else have a back-up system they recommend or a way to notify me? The cabin is Tyvek wrapped, heavily insulated with R21 in the walls and R39 in the ceiling, then it is vinyl sided. I was thinking maybe put a small propane heater on the inside wall and set it to like 40 so if the power went out or a boiler failure and we lost heat it could kick on and keep the place from freezing. Thoughts/suggestions?

 

[savanna]

I'll also add the frost wall, which I believe is 48", was done with insulated fox blocks and an insulation pad was put down under the concrete slab.

 

[Chainsaw]

We have radiant heat in the floor. A wood furnace heated it for many years. We now use a gas furnace and switched the straight water out for a blended fluid.The heat in the barn part without windows comes on only once or twice a day during normal temps so if we lost electricity for a day or so it really wouldn't matter under normal temps. However if the electricity goes out when it is at minus 25 or 35 that could be another story but we do have a Generac and live on site. Still our contractor who is an absolute perfectionist highly recommended we go with a non-freeze protecting fluid. He used RHOGARD heat transfer fluid. It says on the pail; "heat transfer fluid, aluminum/stainless steel safe. Contains multi-metal corrosion inhibitors." Their web and phone listed on the pail is WWW.Rhomarwater.com phone # 800-543-5975

Note we also have insulation under our concrete pad as well as around the outside of it which helps make it stay so warm for so long. As far as loss of efficiency--I'd want to know exactly how much loss there could be before basing a decision of whether or not to use a heat transfer fluid on that.

So Based on my contractor, I'd use RHOGARD in the heating system and for the water system, the idea of a small propane heater sounds good but electric as a backup eliminates the chance of the propane heater failing except for electrical outages of course.

 

[catscratch]

Not really an answer to your actual questions but I have something to throw out there. We built our house 4yrs ago and seriously looked at radiant floor heat. Our contractor (and several others) talked us out of it because it's slow to change temps. Meaning that in KS it can be 15 degrees one day and 60 the next and if you warm your floor up on the 15 degree day you will be miserable on the 60 degree day because the heat doesn't dissipate quick enough. Anyway, I don't know if that affects your thought process on this any but everyone we talked to that had it wished they had gone a different route. On the flip side; I've stayed with friends in the mountains of Colorado who had floor heating and absolutely loved it due to the consistency of the cold weather and the fact that it's awfully nice to put your feet down on a warm floor after a day of skiing. We even put our wet jackets and socks on the floor over night to dry out instead of on top of the treadmill.
Sorry to get off track from your original question, but you might ask around the locals to see if you can find opinions from experience in your area.

 

[savanna]

The pex tubing is in the poured concrete and the cabin has been built so as far as which way we go, there are no questions on that, that part is a done deal. We considered all heat options and went with the radiant floor for many reasons. Im not worried at all about the fluctuating of temperatures. In the fall when we may have a 30 degree morning and a 60 degree afternoon we can leave the floor off all-together if we want and just use the wood stove. Off during the day and load it in the evening.

In 10 years from now when I retire and my wife and I move out there permanently none of this will be an issue. We would know when we lost power and be able to heat the place solely with the wood stove until we get power restored.

The problem is now, not being out there full time I need to know if we lose power or there is a boiler malfunction during the winter months. I either need a back-up fuel source that will kick in or someway without WiFi to notify me the tempos in the cabin have dropped below XX temp.

 

[savanna]

Well it looks like I may have found what I need. After doing a lot of searching, and some people pointing me in this direction, I found a device/service called the MarCELL temperature monitor. It appears to be a cellular only device that you set up in your room and then you set the parameters (temperatures) that you want as your threshold. It looks like I could do a seasonal subscription of 4 months for 14 bucks a month. From all that I am reading it appears as though you set your temps and if the temp drops below your threshold, say 50 degrees, it will send you a text and an email. It plugs into the wall and also has a battery backup. It will also send you a message if the power goes out and the device goes to battery backup.

I think this is all I would need. Should I get a message the temp dropped or power went out I can be at my cabin in an hr's drive or so.

 

[Mennoniteman]

I have floor heat in my cabin and would never do it again, as the system is too slow in responding to temperature changes. But as to answering your question, maybe you should wait and see if you need a backup plan. My cabin is insulated so well that it hardly ever goes below 50, zone 6B central PA mountains. With tyvek, casement windows, sprayfoam insulation in walls, 2.25" under floor, plus having the anti-corrosion rhogard in the floor heat pipes, but we have all the water pipes that can freeze. My garage end has less insulation, I've seen that go down to 40. I put a gravity flow drain system in place for my water pipes but have never had to use it, it seems like I've spent money that I could have saved, and worried unnecessarily about this frost issue.
For a heating system the next time I'd do forced air with a gas furnace, this gives instant heat and A/C that can easily be controlled, and nothing to freeze.

 

[Buckly]

It’s a dilemma for sure. Maybe you could consider not hooking the floor heat up at all until you’re living there full time. Buy a propane heater to take the chill off and use the wood while your there.

 

[Double L]

I have floor heat in my house, and garage for last 18 years. love it. My last addition to my shop I did floor heat and everybody loves it. Everything you touch is at room temp. But as others have stated it does not change quickly. I would look at floor heat and a forced air heat exchanger to do a quick warm up and them have AC for in summer. Buy once cry once I say. dont regret not doing something later..