Home heating system antifreeze?

[mikeR1100R]

With our week-long cold snap here in CT last week I had a pipe which supplied the upstairs baseboard radiators freeze. It thawed luckily with no damage and heat was restored in less than a day. I do not know where the pipe froze although I suspect it was in the "stylish" overhang where our master bath juts out over the deck.

I have heard that the addition of a propylene glycol-based antifreeze can prevent this from occurring. Has anyone here ever done this? How hard is it to do yourself? I have a rudimentary understanding of oil-fired hot water baseboard heating systems and have done basic plumbing repairs and installations. Internet has not been too helpful but maybe I have not looked in the right place.

[BMWRich58]

I've never heard of anybody ever adding a glycol base additive to a home heating system but then,I'm no heating professional either.

 

First thing that came to my mind was insulation or lack of....

[ESokoloff]

Your on the right track with the propylene glycol-based antifreeze but I have no experience in which to offer advice.

[Oldironken]

The company I work for in Tolland CT uses ground source heat pumps for all heating and cooling. They use the non-toxic propylene as the medium to transfer ground temps to the heat pumps. I'd say to look up heating contractors who work with ground source heat pumps.

 

 

[Peter Parts]

All kinds of tech fixes ranging from plastic pipes, heat from anything from light bulbs to heat wires (like those used to prevent roof ice dams), smart thermostat systems, draining, keeping the water running, re-routing pipes, and conducting/isolating heat by canny use of copper or iron pipes (depending).

 

Insulation is tricky because it doesn't make heat and shouldn't be relied on unless you've thought-through the heat flows you are working with.

 

Most heating systems connect to town water supplies for top-ups. Lots of regs to keep town water free of harmful stuff backing up into it. So I don't think I'd add risky chemicals to the system if connected to the town supply and even with a back-up preventer valve, not that that heater water is anything but disgusting already.

 

I don't know anything about how people prepare their cabins for the winter. Which doesn't stop me from posting these uninformed thoughts.

 

Ben

[Rocer]

Mike, do you have other plumbing susceptible to freezing in the same overhang? How hard would it be to get access to the suspect floor/wall area and take remedial action where the problem is? I too have hot water rads (Stelrad) and have survived 12 years with the system with no freeze ups. In a typical winter we have at least a week of peak lows of -25 to -30 C temps. Our 20's vintage cottage is on a stone foundation w/ crawl space so potentially problematic but the bathroom is in an addition that sits directly on a cement pad so somewhat parallel to your applicaion. We bypassed the potential issue of the feed / return rad lines freezing to the bathroom by running the pex pipes along the inside of the wall ie. on the surface of the drywall and covered them with a boxed in base board. However, that didn't remove the problem of the copper plumbing lines freezing from time to time. We've got a handle on that with the installation of typical heat vent cover plates over holes we put in the problem wall to allow room heat in to the pipe locations.

 

I expect you can add antifreeze to your system which, at least in our building code, is isolated from your potable water side. I'm interested to hear about your solutions.

[Peter Parts]

snip

I expect you can add antifreeze to your system which, at least in our building code, is isolated from your potable water side. I'm interested to hear about your solutions.

 

Respectfully, many good ideas, but hydronic systems need top-up from time to time and the water needs to be added with enough force to keep water rads on top floors filled, at least for simple home systems of the generation I have lived with. I suppose there are other ways to do it besides city water and a one-way valve, but that is routine around here. Maybe a one-way valve is considered effective against any contamination flowing back from a heating system; don't know.

 

Ben

[mikeR1100R]

We are on a well and the heating system is completely isolated from the potable water. I think I have a fair idea where the freeze occurred but I am reluctant to start tearing into walls in the middle of winter to assess the adequacy of insulation. I think that for now we will keep the thermostat set high enough on really cold days that the circulator moves the water through the pipes often enough to keep it from freezing again. The more I read on antifreeze in the pipes makes me less sure at this point that is the right course of action.

[Peter Parts]

Furnace pumps use fairly little electricity. So it would be a simple matter to create a kind of freeze alarm out of a old thermostat that keeps the pump running (but not necessarily the furnace) when the outdoors temperature goes below a certain figure.

 

(Likewise, for air systems, good to run the fan at low speed all the time for various good reasons and not much money.)

 

Ben

[ESokoloff]

Respectfully, many good ideas, but hydronic systems need top-up from time to time.....

If your adding water to the system it's because it's got a leak(s).

 

....and the water needs to be added with enough force to keep water rads on top floors filled,....

Not the way it works....

http://www.watertechonline.com/articles/head-and-pressure-in-pumps

 

When I set up a hydronics make-up PRV (Pressure Reducing Valve), I set it so the lowest pressure is about 5 PSI.

Easier on the system that way.

 

[ESokoloff]

The more I read on antifreeze in the pipes makes me less sure at this point that is the right course of action.

 

Not for a DIY.

Seek a reputable water chemistry company.