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[Ill Named]

Anyone on here run glycol or Antifreeze instead of just water in their boiler? I've been wanting to switch to glycol for quite some time now, but at a cost of around a grand here, I've been a little bit hesitant. I've recently run into a few people who just run automotive antifreeze in their boilers, I've even been told by a few companies around here to run it. At about 3 bucks a gallon, it's pretty tempting. Before I go ahead and do it this summer while it's down, I thought I'd ask for an opinion on here first. It's a 4400 if that makes any difference.

Thanks

[slimjim]

 I would not want to be the guy held responsible by the EPA if you ever sprung a leak and got caught, why not simply set the whole thing up so it's easy to drain if you need to?

[Ill Named]

I know 2 other people with the same boiler as mine. Both run glycol in their systems. Happened across another fellow that runs Antifreeze. The reason for doing it would be so if I wanted to go on a holiday in the winter, I could just shut it off and run my furnace while I was away without having to have someone come over and check on it. I know that the furnace will back heat the water, but it'd be nice to not have to worry about it. It is currently set up on water and I'm just thinking about doing the switch. The anti corrosion properties of the Antifreeze make it attractive as well. I'm not too concerned about the epa.

[slimjim]

 Those are all good points, and I'm not trying to burst your bubble, I just happen to be one of those crazy old guys that think the govt is always watching, I've known of people to burn their house because they had a fuel oil leak in their basement and the EPA was making them excavate all the contaminated dirt, that's just fuel oil, I can't imagine what they would do with anti freeze.

[mlappin]

Thing is, I thought I seen on this site why auto antifreeze shouldn't be used in a boiler.

If the water is treated properly it will be just as anti corrosive as antifreeze.

Might be a good time to make a new friend with a neighbor and share a few six packs if you need somebody to watch the boiler?

[slimjim]

mlappin gets a like!!!!!!

[Ill Named]

All discussion about the epa aside, What are your thoughts on the thermal properties of antifreeze or glycol vs water? I'm almost thinking that they would hold the heat better than that of just water and thus use less wood.

I also am at a loss as to why it would be bad to run auto antifreeze in one of these. My vehicles run at or even hotter than my boiler runs. My boiler is currently set to kick in at 150 and off at 170*f. My TDI runs at 90*C (194*f) so temperature shouldn't be an issue.

[slimjim]

Water transfers heat better than an anti freeze mix, it is easier to move through the entire system, therefore more effective. Anti Freeze in a wood boiler should only be used if it is the non toxic type such as No-Burst because a leak is almost certain sometime in it's life cycle, do you really want 200 gallons of anti freeze leaching into your families well water? Where I grew up in western Maine there used to be an old private junk yard, back then, when a radiator was pulled for parts the anti freeze was simply dumped on the ground, I am not an environmentalist but my family lived downstream from that junkyard and the majority of them died from cancer related illnesses, EPA aside, it in my mind makes no common sense to jeopardize the health of your family and neighbors or the future residents, in other words if you do choose to anti freeze your boiler, Please use non toxic!

[LittleJohn]

I run water thru the main loop (aka thru boiler and into structure) then using w2w fphe.  This means I can then run a pressurized system in the house/garage/outbuilding and use glycol.

NOTE: Do not use RV antifreeze, in place of a glycol that is formulated for use in hydronic heating and cooling systems, like Cryo-tek -100.  Cryotek is not the only brand out there, just happens to be the one readily available in my area.  These types of glycols are designed with additives so that they are pumpable down to temperatures below 32f/0c & do not react with any of the rubber seals/gaskets.  Also you have to be careful, there are different types of glycols (propylene, ethylene and methanol) out there and they are not all recommended for contact with PEX, contact supplier about acceptable glycols and mixes (generally no greater than 50/50, by volume)

P.S. If I would have mixed by entire system to 50/50, CB eClassic 2400 and all systems (total of 400 gallons, so about 200 gallons of glycol); would have cost in the area of $4k-$5k.  Plus every year I get to check the glycol to make sure it does not go bad, read about glycol "souring", aka going bad from overheating or boiling the glycol mix.

[Ill Named]

Alrighty then. I guess I'll just stick with water. With regards to a leak happening, I don't imagine that all the treatments that I put in with the water, it cannot be to good either. How often are you guys draining and refilling your boilers?

[Goat Herder]

I have been debating this same issue for "year two" with my Wood Master Wood Furnace.  Being a noob with one hard winter past, I have been concerned about the risk of the fire going out and the sytem freezing.   I am not sure how big a risk this is, or how fast this could occur. 

This post has helped me to conclude to just run water as we do have nearby ponds and a well on the farm. The risk of contamination is substantial. 

If a person needs to leave town for awhile, do most just drain the sytem? 

[LittleJohn]

I would not be concerned with contaminating ground water with a leak from your boiler; because you boiler holds 1000 gallons (probably less but easier MATH) and and max 50% gylcol or 500 gallons of "pure" glycol.  Every "Acre-foot" of lake/pond/stream contains some where around 325k gallon of water, so another 500 gallons would not matter. QUICK MATH -> your 500 gallons of gycol would increase an Acre-foot of water to approximately 0.15%
***Also if you use propylene gycol, it is relatively safe to drink.  Meaining you can drink a little and be OK, but drink alot and its time to go to Hospital (you won't die, probably just wish you did)

Goat Herder - It depends on what "awhile" means? and what the expected temperatures in your area will be will gone.  I see two typical solutions; you could either find a neighbor to fire for you while you are gone, or you drain and blow out all the lines to your OWB. 

Or install a horrible and expensive GAS burning backup boiler; in my setup I have a backup/booster LP boiler that I coudl use in event that I will be gone for more than a few days and neighbors are unavailable.

[slimjim]

Good post on the help from neighbor, I still wish I could do math like that but still would not want the leak into any ground water, a high percentage of my family died from cancer and I think a big part of that was caused by the junkyard upstream dumping automotive anti freeze for years.

[LittleJohn]

...a big part of that was caused by the junkyard upstream dumping automotive anti freeze for years.

In general YES automotive antifreeze is bad Ethylene glycol I believe; where as most hydronic systema run Propylene Glycol.  The funny part is a high number of foods you eat or consume from a grocery store contain small/trace amounts of propylene glycol, because it is a preservative; heck its even approved to be added to dog food.

http://en.wikipedia.org/wiki/Propylene_glycol

[mlappin]

Actually straight water transfers heat better, my brother in law when he was still racing stock cars ran nothing but straight water in his. Ran cooler on water than with antifreeze.