Hydronic Heating Antifreeze

[Jriddle]

I have a hot water heater with a heat exchanger in it. This water heater call for a non toxic antifreeze. I installed a plate heat exchanger on the engine loop with a pump. Now here is the problem. The water heater calls for some type of antifreeze that cost eighty bucks a gallon. If I use this antifreeze I will still have a problem with my engine loop if the plate heat exchanger leaks. What have you done in your systems. Should I get different water heater?  Is this something to worry about?? I have looked in the archives and didn't find much.


John

[AC MC9]

John,

I have some experience with the glycol side of things. 1st using non toxic glycol for your water heater is preferred due to if you have a leak in the system and you DRINK the hot water you may not get as sick or die, however if you DRINK large quantities of non toxic glycol you will get sick or even die. The term "non toxic" only refers to how toxic the glycol is. All glycol is toxic if taken in the approiate quantity. Now in regards to your heat exchanger. If it is a brazed type exchanger than there is a low chance that it will leak. If it is a plate type that uses "O" rings between each plate there is a higher chance for leaking if you do not properly maintain the glycol.

My opinion on this is: 1) if you do not have small children in the unit, then I would go with the same glycol you are using in your engine. (This is what my plans are) 2) If you have small children in the unit then better use the nontoxic glycol and be on the safe side should the heat exchanger fail. In my opinion it is easier to fix a engine due to improper glycol that to have a child sick or god forbid die from ingesting some "more toxic glycol".

Just some information: Nontoxic glycol is better known as propylene glycol and you should be able to find it at or very near the same price as the more toxic glycol (ethylene glycol). One other thing you need to be carefull of the inhibitor package of the glycol.

I hope this helps.

Arsenio

[NewbeeMC9]

I vote for the low-tox in drinking water side.  two HXs have to leak for you to get any in the drinking water.

Do you have more info on your bus, water heater, etc?

Also remember if there is a leak, it will be from the higher pressure side to the lower pressure side.

If you keep your fresh water tank higher than your heater system then you will have much less to worry a bout.

[Jriddle]

I stand corrected the guy at the store was quoting six gallon price. Thanks for info as I called him back and found that I had misunderstood him. They don't carry this stuff and I would need to order six at a time.

John