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Old 10-01-2008, 02:18 PM   #1
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henryj's Avatar
Join Date: May 2008
Location: Ontario
Posts: 641
SUN #597
Winterizing Propane and Water 2

Some tips for winterizing the water system...
I learned this year that there are two kinds of plumbing antifreeze--ethanol or ethyl alcohol based and propylene glycol based. They're both pink, the bottles look the same, and you can identify the propylene glycol one only by reading the fine print on the ingredients or the health warning. Apparently propylene glycol does not dry out rubber fittings and seals the way ethanol does. I know this used to be a problem when ethanol was first added to gasoline, but believe the car manufactures have fixed that now--don't know about RVs though and some pink stuff will definitely be sitting up against the seals of the dump valves and in the taps. Anyway, I bought 2 gallons of propylene glycol at Walmart last month when we were in the US. It's way cheaper than in Canada and only about $1 more than ethanol. Any members looking for it in Canada, it's in the plumbing department at Canadian Tire, but not in the RV. A warning if necessary... don't confuse ethylene glycol--automotive antifreeze--with propylene glycol--plumbing antifreeze. The difference is just as deadly as the difference between methanol and ethanol.

Pipes burst when water expands as it freezes. Even a cast iron engine block won't contain it. I buy a little insurance by opening all the taps after winterizing.

The city water inlet has a back flow valve with a small plastic button in the middle that should never be pressed in. The small amount of pure water that remains behind this valve after winterizing has never created a problem for me--likely the antifreeze slowly diffuses into this water and prevents it from freezing. However, for some people this button is like a wet paint sign--they just have to see for themselves. If you're one of those people never push in this button with any force. It is very lightly spring loaded and any water pressure behind it could lead to a break in the seal and a painful replacement. If you feel you really must push this button, open all the taps first to release the water pressure... then go take a nap. If you still must push this button after sleeping on it, it will depress very easily, a handful of water will flow out followed by a handful of pink stuff and you can have the satisfaction of knowing there really is no water left in the system. I guess I'm a wet paint kind of guy, but I know doing this makes no difference because half the time I forget anyway... but I did it today.

Putting antifreeze into the hot water tank is not a good idea--it will take a long time to flush out and I've heard gets very unpleasant if you forget and crank up the heat with antifreeze in the tank. In an RV the tank is lying on its side. It is physically impossible for the small amount of water left after draining the tank to break it because the water easily expands up the curve of the tank sidewall as it freezes.

I dewinterize like I winterize by running 2 jugs of water through the lines using the water pump. That way the water pump gets rinsed out too and I remember to turn the winterizing intake valve back to its summer position. Then I hook up the city inlet and run plenty of water through.

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