Using a vacuum pump to de-winterize

[BicenTw]

We live in PA and must winterize soon. I would like to use the AS this winter to travel in cold weather to MI for ice boating and NY and NH for skiing. Has anyone used a vacuum pump to remove antifreeze and water thoroughly? Where would I add an access valve to the system if the plumbing only has one drain on the WH and one outlet for the cold water into the grey water.

[HowieE]

If I understand the function of a vacuum pump it would takes days to boil off the water in the system.

I use a vacuum pump to boil off the refrigerant in an air conditioning system. It take hours and that is with a material that has a relative high vapor pressure.

Why aren't you considering a compressor. That take minutes to blow out the trailer.

[Protagonist]

Originally Posted by BicenTw

We live in PA and must winterize soon. I would like to use the AS this winter to travel in cold weather to MI for ice boating and NY and NH for skiing. Has anyone used a vacuum pump to remove antifreeze and water thoroughly? Where would I add an access valve to the system if the plumbing only has one drain on the WH and one outlet for the cold water into the grey water.

I don't really think a vacuum pump would do any better than using compressed air at the municipal water intake to blow out the plumbing.

[overlander63]

Why not do the same as most other people, and simply connect a water hose to the fresh water inlet, and turn on the water?

[HowieE]

Lets back up a step or two. If you are going to NY,MI for short stays in the winter you don't want to consider using the water system in the trailer at all. There is not enough propane available to keep the trailer from freezing in those areas.

Carry gallons of water for drinking and cooking and carry anti freeze for what you put down the toilet and the traps. The larger tanks, while they will freeze if left with out an antifreeze mixture in them , should not freeze to the point of damaging the tanks if you are adding antifreeze each time you use them.

If your trailer has copper piping you don't want to take any risk of it freezing. Blow it out drain the hot water heater and leave it dry.

[nrgtrakr]

You'd likely need to re-winterize before returning home, no?

[BicenTw]

OK, I should have used the term FLUID EXTRACTOR. (see link below or GOOGLE ) to avoid working outside the trailer I would extract all the antifreeze, replace it with water then reverse the process before going home. But Howie has a point. The extreme cold could be more of a worry than justifies having running water. To extract water/antifreeze I would seal tubes around each faucet place one tube in the liquid I was introducing and the other tube I’d connect to the fluid extractor. The change in color coming out would indicate when I’d removed most of the unwanted fluid. Squeezing off the feed line early on is necessary.


Great deal on MityVac MV7300 at ToolTopia.com

[Richard Kern]

There is a small fitting that screws on to your outside shore water inlet that lets you blow out the water with a tire nozzle. Keeping your lines open when the outside temp is below freezing is risky. Better to just use bottled water and leave your lines full of antifreeze.

[JCWDCW]

It takes at least 40 psi to blow out the lines properly. Not sure what the OP is trying to do with his vacuum pump, but max negative pressure with a vacuum pump or the fluid extractor is only a bit less than 15psi. ( atmospheric pressure 14.7 psi pushing into a vacuum) Since he already has air pressure for the fluid extractor, just use it to blow out the lines and drain to the tanks.

JCW

[morganobenn]

I think using a vacuum pump on the tanks puts the tanks at risk of damage. They are designed for pressure not a vacuum; vacuum could collapse them and crack the walls. If the lines are clear of water so that ice won't burst them, you are probably safe. A little water left in the tank has plenty of room to expand when freezing.

[Silver.Sanctuary]

Originally Posted by morganobenn

I think using a vacuum pump on the tanks puts the tanks at risk of damage. They are designed for pressure not a vacuum; vacuum could collapse them and crack the walls. If the lines are clear of water so that ice won't burst them, you are probably safe. A little water left in the tank has plenty of room to expand when freezing.

I am guessing that the fluid extractor is an attempt to save the anti freeze and re-use it?

Probably not worth the effort since when you put it in, it mixed some with existing water even if you blew it out with air first... multiple uses could weaken the anti-freeze and result in the whole thing freezing up. $$$$.

Somebody suggested that there wasn't enough propane to heat the unit so that the tank areas are protected... and although that may be true, if you have electrical hookups you can use a Dyson heater with thermostat to heat your trailer. Many apparently use it for its propane saving nature as well as the quiet operation.

My 2004 has tank heaters and so if your unit has them, it could help if you really want running water. Michigan and Vermont are cold climates in the winter, so the safe money is to leave that system dry and use anti-freeze to add/flush the black tank (toilet) when used. Gallon jugs of water are pretty cheap at Wal Mart, and would store easily even in my 22 foot unit.

If you were going to a warm climate, it might be a different story.

[overlander63]

I must be missing something here. It looks like you want to spend $90 on a tool in order to save $8 worth of antifreeze, and waste about a half hour each use.

[BicenTw]

In a marine environment you can’t be too careful with petroleum and toxic products. That’s why I used the fluid extractor on the boat to avoid a spill into the bay. The thorough job the extractor does on the antifreeze leaves very little for the following water to dilute. One year I even tried cheap vodka as a chaser/solvent before adding water to the system. morganobenn was concerned about the tanks being compromised. I’m only evacuating the P-traps then adding a-f. The The advice I was looking for was the best location to install two valves H/C with easy access. The storage location of the AS doesn’t have electric service for my air compressor and I cannot allow the AS on my property. So far I’ve cut the two lines nearest the floor in the bathroom and I’ve removed most of the water. I’ll solder in two valves tomorrow. I agree this is not a popular approach but it is a lot easier to work in that storage location than it is to frequently move the trailer just to get to electric power.