Radiator in Garage ~ Antifreeze?

Nyjumpee

Hello! First time poster here. . looking for some advice on a few issues please!



We're moving into a foreclosure as a "fixer-upper". It's 4500 square feet, 3 levels and has 1 boiler, 2 hot water makers and 7 zones on the heating system including 1 in the 3 car garage.  There was one radiator in the laundry room that was burst from freezing apparently but the rest of the house is okay surprisingly enough!



The thermostat for the entire basement appears to be in the garage?



I don't want to keep the garage heated all winter long and, if I have to keep it just above freezing to keep the pipes from bursting, what's the best option?  Antifreeze? Drain just the zone in the garage?



Also, would like to be able to have a thermostat in the basement/ground floor without it relating to the temperature in the garage. . .can I simply MOVE the thermostat or do I need to add another zone?



My plumber suggested replacing the water in my boiler system with Cryo-Tek. . .said it would be "about $800 to $1000".  Does that sound like a lot of $$$ to do that?



Thanks so much and look forward to any and all advice!

Zman

Questions

Antifreeze is a good idea if your pipes are located in areas prone to freezing. Your garage sounds like one of those areas.

Yes, if you want the garage at a different temp, it needs to be on it's own zone.

No pricing talk allowed. A typical baseboard system might hold 15 gallons. 30% glycol is pretty common.

Opinions vary on inhibitors. I don't think every system needs them. Systems with corrosion issues due to bad tubing is a good application.

Jean-David Beyer

My hot water heating boiler is located in my garage, as is my indirect fired hot water heater. The system has no anti-freeze in it, though it does have some Sentinel X-100 in it to protect the aluminium (British spell checker?) heat exchanger.

The boiler is a mod-con with outdoor reset. I do not specifically heat the garage. No heating zone there, but the pipes do run around in there. I insulated the pipes with 1/2 inch black foam from Home Despot. Normally, there should be no freezing, and there has been none even the night it went down to 2.8F or whatever it was. A domestic hot water pipe in the house did freeze.

The outdoor reset increases the temperature of the water supplied to the house as the outdoor temperature goes down, but the reset curves are adjusted so that the thermostats in the house are just upper limit switches. So with near constant flow in all the pipes, I doubt there will be a freezing problem. The only time I was really worried was when storm Sandy cut off the power for 6 1/2 days. Fortunately, it was not terribly cold outside, though it did go below freezing.

Also, even if the house did not call for heat, the controller in the boiler will turn on the circulators and switch into low fire it it gets too cold, and shut off if it gets up to about 45F.

And after storm Sandy, I had a natural gas fired backup generator put in.

Bob Bona_4

It would be a shame to see the rest of your hydronic system suffer from the ongoing service headaches and corrosion potential by adding glycol to it just for the garage zone. It is bad news.

If you MUST glycol it, a better option would be to isolate that zone via a heat exchanger and glycol just that loop, sparing the rest of the system.

The basement/garage zoning piping would have to be assessed to see if they are independent for zoning.