Using scuba tank for blowout winterizing?

[JohnF]

I don't have a shop compressor.

But I have over a dozen scuba tanks (diving addiction...). I have an adapter which takes the low pressure inflator hose typically used for a BC and converts it to a tire inflator - one that fits schraeder valves.

So I'm thinking this would be a fantastic source of cheap, portable air for blowing out the water lines.

Anyone done this before?

I have read somewhere that ideally you're using a lower pressure - something like 30 or 40 psi on the blowout valve. But a low pressure inflator off a scuba tank regulator would more typically be about 130 psi or so.

The blowout valve body I have appears to be brass. The trailer is a 2011 scamp 13' (or will be, pick it up in 11 days).

[Joe Z]

My portable tank has 120psi and no regulator valve...... I just close all my faucets and give it about a two second pump up with the portable tank......have someone inside or yourself and open a faucet at a time...you can actually hear the pressure going in and with a little practice its very easy to know when it has a little pressure built up in the lines.... repeat this a few times til the lines are clear.......don't ever pump it up to the full 120psi as your surely to bust something. You do this at your own risk LOL
Joe
Joe

[JohnF]

Makes sense - add a little at a time and the overall volume of the line will cushion the buildup of pressure so it is gradual.

Do you bother with trying to bypass the hot water tank or just drain it first and then blowout? That's a lot of air volume in the tank (6 ga), but I'd think it would be fine to not mess around with installing a bypass valve. What's your experience?

[Casita Greg]

I would recommend not closing all your water valves when applying pressure. If you wish to rotate faucets, fine, but keep one open at all times when you are applying pressure to the system. First, with all valves closed, you risk bursting your plumbing lines if you aren't paying close attention to the task at hand. Second, you will do a much better job of blowing the water out of the lines with the valves open to allow the expulsion of anything in the lines with a continuous flow of air. Keep your valves open and blow them out until the water quits coming out. Don't risk "pressurizing" your water system. And don't forget to pull your HWH anode and drain the heater too.

[floyd]

Does your new Trailer have a hot water tank, flush toilet and shower?
The approach to winterization might be completely different depending on how the trailer is equipped.
I live in northern Illinois and I have never used air pressure as part of my winterization. My 2004 Scamp 13 trailer has every option and has been witerized 7 times with good results using only antifreeze.

[Daniel A.]

Just a thought, I use a pressure reducer when connected to city water which is typically 100 psi and reduced in homes to 60 psi.

Blowing the system with air sure will get the job done but may leave you with leaks in the spring. Myself I would use a pressure reducer or leave the low point open. I'm not sure your water pump could handle that kind of pressure without disturbing the gaskets.

[JohnF]

Our new 13' scamp has bathroom & shower so it has the full gray water tank, black water tank, hot water heater, fresh water tank plumbing.

Given how easy the blowout procedure is for this small a trailer and my readily available portable air sources, I'd rather not have to stuff lots of antifreeze in the fresh water side of everything - just the traps and the black & gray water tanks.

Plus, I anticipate a bit of "let's winterize, wait - let's use it again" sort of weather cycle which makes the non-blowout winterizing process more involved (and just plain wasteful of RV antifreeze).

[peterh]

Others have echoed my concern about the high pressure in a dive tank, so I'll skip over that and simply suggest a 10gal air carry tank filled at your local gas station or friend's compressor. It's what I use . . . They hold 100psi or more, which works out to 40 gallons of air or so that you can use to blow the lines out, and I see them at everything from garage sales to Harbor Freight for not much money.

[Alf S.]

Hi: All... I just finished the blow out. I used my air pig with about 100psi. Opened all taps& held flush valve open on the toilet. Then lowered the outside showerhead and opened it. Then watched it blow water until no more came out. All taps remain open for storage and the low drain plug is pulled and drained... so's the anode rod in the hot water heater and the 12V. pump was run 10 sec's. then the waterline to it disconnected. The fresh water tank is also drained.
Now all I have to do is add RV Antifreeze to all the drains and a bit in the black tank.
Next problem is to remember in the spring... where I left everything!!!
Alf S. North shore of Lake Erie

[bernie]

You can buy a small 12 volt compressor for just a few bucks that will work fine. I quit doing the blow out because of problems getting the pump re-started. Some people even reported having to repair the pump because of a dry diaphram. The blow out is easy and cheap except for the potential pump problems.

[Bruce H]

I never use over 40 lbs of air pressure. My concern with higher pressure is about blowing out a fitting or rupturing a line in some hard to get to place.

[john warren]

just buy an air regulator and quick disconect. you will use it for everything from pumping up bike tires to spraying cleaner that way.

[cpaharley2008]

If you tank says 120 psi, then you are exerting 120 psi on your lines, you can not control pressure with your valve, that merely controls the volume. You can blow your lines with 120 psi, I'd advise against that until you get a pressure reducer. It is a common misbelieve that you can control air/water by reducing the flow, that does not reduce the pressure, only volume. The pressure is constant unless you reduce it.