Friday, April 1, 2011

Antifreeze for Your Outdoor Wood Furnace and Other Winter Questions:

We've had lots of people asking about adding antifreeze to their systems. Below are some of the basic answers to your questions.

Do I have to worry about my outdoor wood furnace system freezing?

No. With 180 degree water, the system will never freeze as long as the outdoor furnace is running and the pump is working. Even without wood, the furnace will absorb some heat from the indoor loop further preventing freezing. The outdoor furnace is highly insulated which minimizes heat loss, even in the coldest weather.

What should I do with the outdoor furnace if I go on vacation in the Winter?

This depends upon how long you plan to be away, and how cold the weather will be while you are gone. If you will be away for a weekend, you can turn down your indoor thermostat, fill the furnace full of wood and turn off the draft fan, and enjoy your weekend away.

If you will be away for more than a weekend, you should still turn down your thermostat indoors, but you should make arrangements to have a friend or neighbor feed your furnace. If you will be away for an extended period of time during the winter, you may want to use antifreeze. As always, please follow all manufacturer's guidelines.

Should I use antifreeze?

There are many benefits to using antifreeze – in addition to freeze protection (which is a very small risk in normal conditions), antifreeze also provides some corrosion resistance and may increase the life of your pump. The downsides to using antifreeze are as follows: 1. It is very expensive, 2. it needs to be “recharged” annually, and 3. it reduces efficiency of heat transfer up to 13 percent.

For customers who wish to use antifreeze, Hawken recommends the environmentally-friendly propylene glycol similar in formula to Dow Frost or Noble Super NoBurst. Be sure to follow the anti-freeze manufacturer’s recommended percent mixture to give you the freeze protection you need.

What happens if we have a power outage?

In a power outage, most home heating systems will not operate because they require power. If power outages are common in your area, we recommend that you install a generator.

If you have any other questions about freeze protection or anything else to do with your Hawken furnace please give us a call (231) 861-8200.

Posted by Don Squire - Hawken Energy Outdoor Wood Furnaces
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  1. When we go away for more than a weekend, we rely on propane as a "backup" and keep the house heated to 50 degrees. With the pump circulating the water through the house, we haven't had any problem with the water freezing!

  2. Hey pattib this is great. Even I do the same. Whenever we go outside the house I always keep the house heated so it helps to reduce the electricity bills. It also helps to avoid the other water freezing problems.
    Wood Stoves

  3. I'd like a good wood furnace in Winnipeg. Something that doesn't rely on electricity is always helpful to have.