Freeze proofing the toilet flush valve

Drake-SUN

Senior Member
Joined
Aug 11, 2010
Posts
210
Location
Newport News, VA
I blow out my lines each fall when I winterize and pour some antifreeze down the sink traps, and all has been well, until last spring when I opened up the camper. My toilet flush valve had cracked, I am assuming, due to water that remained in the valve when I blew out the water line to the toilet, even though I blew out the line with the valve open ( in the flush position.). Should I just disconnect the valve ( kind of a pain), tape some insulation around it, ( less of a pain) or what?

Good to be back on, reading posts from you good folks...life has intervened and taken most of my time...hope to be more "mouthy" now.
 
Drake,

I do not know your vintage toilet valve, however this is mine and the flush valve creates a natural trap.



I myself blow out the system with compressed air. In 11 years of doing this I have not had an issue. BUT.... what size compressor do you have? I have a 3hp unit. May be bigger than needed, but that is what I have. If you do not have enough volume of air pushing it will not blow out all the water. I hook into the water system with a full 1/2" tube to allow the volume of air to flow and not through a schrader tire valve screwed into the fresh water inlet like they sell in the camping stores. Also you can come back a day after your blow out and blow again. Water sticks (wicks actually) to the sides of the pipes. In a few hours the water film/drips will break tension and lay/collect in the bottom of the pipeing. Then blow again and more will come out.

The instructions are here and they use the antifreeze or drain method. By unhooking the feed hose the water can evaporate out as long as you have a few days before freezing.

Proper Bowl Cleaning; Winterizing - Dometic SeaLand 110 Owner's Manual [Page 4]

Hope this helps

John
 
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I use this type of blow out hose. I can hook my compressor to it and let it run. I open each valve individually till it blows air then I open all. Leave air off awhile then blow again. put a 1 1/2" PVC pipe in toilet to hold flush valve open. I also use it to blow out my rv water hose and garden hoses.

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I think is was Camping world or eBay. I've seen others, after I bought mine that has a ball valve shutoff, but that can be added to mine if so desired.
 
I had an old garden hose, a short piece of hose a clap and an air fitting. You do not want full air pressure so use a compressor with a regulator down to some thing close to 40 PSI.
 
Agree on the lower pressure, the 40psi range is good. You need enough pressure to push the water, you need enough volume to not run out of "umph" when blowing out the lines.

Point making, a little tire inflatetor compressor that can produce 80psi for a tire at 0.5 scfm is not going to work well when regulated down to 40psi and trying to blow out a camper line. Since there is so very little volume pushing behind it, the air flows over the top of the water in the line and never carries it "all" out.

Also a heads up on how your camper is made when using the fresh water inlet as the blowout source. Not all layouts are created equal. On our T2499, the city water line was in the back of the trailer, the last leg of the water feed. The water pump was at the other end of the piping. The low points drains where in the middle. In this case the pump became a dead leg where water blow out from the fresh water port left several feet of un-blown line from the pump forward.

Our T310SR was different but still a concern. Point: If using the city water port as the blow out source, check you have do not stranded water in the line from the pump. And or go back and unhook and blow out that line.

I changed both campers to allow being able to blow from the pump forward eliminating the issue.
 
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Also a heads up on how your camper is made when using the fresh water inlet as the blowout source. Not all layouts are created equal. On our T2499, the city water line was in the back of the trailer, the last leg of the water feed. The water pump was at the other end of the piping. The low points drains where in the middle. In this case the pump became a dead leg where water blow out from the fresh water port left several feet of un-blown line from the pump forward.

Our T310SR was different but still a concern. Point: If using the city water port as the blow out source, check you have do not stranded water in the line from the pump. And or go back and unhook and blow out that line.

Very nice info. I might have missed the dead leg.
 
My trailer is in storage with no electric service available. I toted my compressor and generator over to blow out the lines - once. Boy, what a PITA.
I now drain and use antifreeze. I think that's the way to go if there's any danger of water collecting in a tight space after a blowout.
One-and-a-half gallons does all the lines and traps. The Rockwood came with an exterior antifreeze pickup, water pump selector valve and WH bypass. All are outside accessible in one "plumbing" bay.

Teach
 
I do both. I blow my lines then fill with antifreeze so water in lines don't dilute antifreeze. I leave all faucet valves open when finished. I then tanks into my blue boy and dump
 

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