Winterizeing air pressure

Yes, stay with air pressure that's close to your working water pressure or slightly less.

Bill

1/2" PEX is what is used for plumbing lines

Not sure where/why 'factory' would warn of not using pressures over 45#?

Standard water pump has a 45# discharge pressure.....upgrades/optional water pumps have 55# discharge.
Water pressure regulators come pre-set at 45-50#
And if PEX got really hot it still is rated higher

PEX
Pressure/temperature rating 160 psi at 73°F
Pressure/temperature rating 100 psi at 180°F
Pressure/temperature rating 80 psi at 200°F


40# air pressure is sufficient to blow water out of lines

George H wrote:
Saw a recommendation to use 80 lbs. air pressure to blow out water lines.

Where? I've never seen anything that high.

80 psi is too high...and unnecessary.
Go with about 45psi. It will do the job very nicely.
I have been using 45psi for well over 20 years.

I use one of those tankless 12VDC air compressors hooked up to the city water connection using an adapter. I can start this up with my 12VDC compressor sitting on the tail gate of my truck using 12V connections to my trailer battery bank. This starts up with low pressure since it does not have the air tank so I have plenty of time to walk from the air compressor to each of the spigots around the trailer to open lines up one at a time allowing the water in that path to go down the sink drain or directly on the ground etc...

Doing this shows my compressor pressure only getting up around the 40lbs level or so.

When I am blowing just air then I shut it down and add some pink stuff to the P-traps... Opening the hot water side spigots does some draining of the hot water heater as well.

Of course before I do any of the blowing out of the lines I use the low water points to drain the water first including openingboth the hot water and cold water spigots to allow gravity to help drain the lines quickly.

Some of the hot water tank does not usually all drain out but I never really worry about it as there is plenty of room in the hot water tank for expansion if it should freeze.

This method works great for me here in the Northern Neck Virginia area where we really never get long freeze-up periods... It may get down to freezing over night but most often warms back up the next day...

Since we camp off-grid alot in the high country around here over the winter cold months doing the blow out method is very handy for us as it does not take much time to accomplish and the good part is I can revert back to using the water lines and tank by just adding fresh water the next day...

Roy Ken

That 80 PSI recommendation was in this weeks RV TRAVEL Newsletter, I wanted to get this discussion out there for those who might be influenced by that article.

Gary Bunzer sure did say this":

" And since all the faucets and valves will be open, it will be safe and quicker to use 80-PSI. "

RVs are supposed to be factory tested to at least 100 psi. RVwaterfilterstore.com recommends operating at 60 psi (for adjustable regulators) and that's what I have ours set at. Some CGs have pressure well over 100 psi and 100 percent of campers won't have a regulator and you don't hear about RVs blowing anything inside from high pressure. I've seen CG pressure as high as 140 psi and it reportedly can get as high as 200. 100 psi is nothing for PEX piping. It has a memory and even if severely kinked or stretched will return to it's original shape & size.

If you have a small portable electric compressor it's unlikely you'll have to worry about too much pressure as you won't getting much cfm to keep pressure up with an open faucet/valve. Regardless of your compressor size, adjust the regulator down to a level you're comfortable with. I used to use a Porter Cable pancake compressor and now use my shop compressor and turn down the regulator a bit (usually set at 90 psi for air tools). I used the pancake compressor for winterizing several winters and never had a problem but some are concerned these will leave some moisture in the lines. Even if some water remained in the PEX lines they can withstand repeated freezing.

There's two types of winterizing adapter fittings for a city water or black flush inlet. One uses a standard quick connect fitting and the other uses a schrader valve. If worried about pressure, use the schrader valve adapter and fully open a faucet/valve first then go hold your air chuck against the schrader valve until all the water is expelled. Or use the quick connect version and turn your regulator down to 45, 60 or what you are happy with. I use the latter as it's easier for one person and you don't have to keep running outside when it's rainy and/or cold.

Use a water trap and filter to keep remove moisture and undesirable stuff from getting inside your RV.

If all of the faucets are open you can't develope much pressure. You may have 80PSI available in the compressor but it goes to near zero once you let it out of the hose!

I just did mine yesterday. I set the air at 30lbs. I didn't have any open until I went inside and opened and drained 1 at a time. Worked good.

You can use higher psi if you want, but it isn't doing anything better. Maybe a couple seconds faster.