Winterizing Question

wa8yxm wrote:
Screw adapter in and set regulator on Compressor (I used a 6 gallon pancake 150 PSI job) to 50 PSI.

Let 'er blow. When it ran out of air go inside and .......

LOOP By now the air compressor has recovered so BLOW again.. When it runs low stop blowing and have some coffee. ENd loop
I ran 5-10 cycles of the loop.. Eventually I ran out of coffee :).

If all you do is take an expired or scrap (but not rusty or damaged) propane tank and “T” it into the system between the compressor and regulator you will dramatically reduce the number cycles required.

Because of the length of air hose I use for projects in the yard I made up a portable reservoir with a discarded 100 pounder that permanently lives on a hand truck. I replaced the valve with a T that has both a male & female quick disconnect fittings. By putting the tank near my work the volume of air flow is not restricted by a long run of small diameter line.

LarryJM wrote:

JaxDad wrote:


That could only be an issue if you don’t blow the lines out properly. I did an experiment a few years back for sceptical friend to show him how well it works. I took a 100’ coil of clear fuel hose and hooked to to tap, then with it standing vertically hooked it to the compressor with the regulator set to 50 psi. There wasn’t a drop left in the line.

The issue arises when someone uses a very small compressor that can’t maintain the required pressure for very long, or just doesn’t perform the task correctly.

Depending on who you ask 50psi is more pressure by almost 2 times as what a lot of folks recommend for the max air pressure to blow out your lines and is from what I can tell at the very max of what anyone recommends.

Larry

The water system is ‘rated’ at 50 psi, city water pressure, that’s not the burst point. In an air system PSI is the ‘driving force’, volume is the amount of work. Sort of like the air version of volts and amps.

Large volume is relative, of course. A cheap 10 gallon, 4ish cfm compressor does fine for me. The tank size is pretty much irrelevant here since it's running basically continually during the process. A massive body shop compressor is not required by an means.

If your RV is set up for cold weather operation, using the water system in below freezing conditions (with the furnace on etc.) is fine; it's designed for that. There is a lot of variation in how well RVs are set up for cold weather use, though, ranging from not well at all (pipe runs exposed underneath, etc.) to reasonably decent (pipe runs and tanks all inside the insulated envelope, maybe tank heaters, double-pane windows, etc.) Obviously without heat any RV will freeze eventually if the average ambient temperature is below freezing.

I don't have a need for a large, big volume air compressor so I use RV antifreeze. Awhile back I used my small air compressor to blow out the lines in a Class B until I ended up replacing the toilet valve two years in a row. So as suggested earlier if you don't have a high volume air compressor then use RV antifreeze.

JoshuaH wrote:
I was wondering, is there any reason why I can't use compressed air to blow out all the water in the lines? I have an air compressor, wouldn't be hard to make an adapter that will hook to the water connection.

Thanks!

No need to make an adapter there are two different versions of it already on sale at your local RV place even Wal*mart will have one

One has a "Stem" capped with a small rubber cap. This Stem though nto threaded is the same size as a tire valve stem.. The other one has a "Quick Connect" fitting (I forget which style) that matches the chuck on most personal air compressor hoses (Type M I think but do not quote).

And no there is no reason not to do it that way. IN FACT I did it that way before I switched to the "S" method (Drive South).

HOW I did it.
Drain and bypass water heater. Drain fresh tank. Open all valves including low point. Screw adapter in and set regulator on Compressor (I used a 6 gallon pancake 150 PSI job) to 50 PSI.

Let 'er blow. When it ran out of air go inside and force cycle the ice maker (Optional remove solenid to warm place). then shut off water valve to ice maker (Force cycling the water in the line will drain into the main lines in the rv) Open the intake strainer on the Water pump (Place towel below it to catch water) and drain it.. Run pump for like a minute then turn off and re-assemble trainer (Run pump DRY of course to clear it and it's outlet line)

LOOP By now the air compressor has recovered so BLOW again.. When it runs low stop blowing and have some coffee. ENd loop
I ran 5-10 cycles of the loop.. Eventually I ran out of coffee :).

Now I'm not getting any gurgle sounds. no more water out. Close valves Flush toilets. I had a home dump station so I dumped (you can do this at last campground) and added pink to toilets and sink trap and Flush toilet once more (Let some pink into the black tank) and re-pink it.. Head in to house for winter.. Returning daily to RV for Radio Nets (it's my ham shack after all) but not using plumbing save to sit on (Lid closed). (Like Guitarist Joe Walsh, not to be confused with the other Joe Walsh, My "Radio Room" has plumbing.. That way when you got to go somewhere you don't have to miss your turn on the net you are checked into since where you have to go is where you already are).

That makes it sound like you think you’re going to put water back in the system each time you use it during the winter. That is a VERY dangerous proposition. You will have a lot of lines in places you can’t heat enough to prevent freezing.

Well I didn't think that would be a problem as long as we kept the furnace running. I don't camp when its really cold, but possibly below freezing at night, 30s-40s during the day.

I always blow the lines out first with about 40 psi, and then pump thru RV antifreeze, just to be sure.
The cost of a few gallons of antifreeze is nothing compared to the cost of possible water damage or replacing burst water lines. Especially if the line is snaked thru a wall/cabinet.
Dont' forget to get the water out of the hotwater heater bypass...

JaxDad wrote:


That could only be an issue if you don’t blow the lines out properly. I did an experiment a few years back for sceptical friend to show him how well it works. I took a 100’ coil of clear fuel hose and hooked to to tap, then with it standing vertically hooked it to the compressor with the regulator set to 50 psi. There wasn’t a drop left in the line.

The issue arises when someone uses a very small compressor that can’t maintain the required pressure for very long, or just doesn’t perform the task correctly.

Depending on who you ask 50psi is more pressure by almost 2 times as what a lot of folks recommend for the max air pressure to blow out your lines and is from what I can tell at the very max of what anyone recommends. Of course the more pressure and larger capacity the better the job, but the question which is an unknown is for your particular trailer (especially with regards to its specific configuration like were the inlet for blowing out is in relation to say the water pump and low point drains) is just what is that pressure and air compressor capacity needed to do the job right and avoid the issue I mentioned. If you guess wrong it could be a fairly expensive mistake and you really are sort of guessing.

Larry

LarryJM wrote:
Biggest issue with just blowing out the lines is that if your system has a low run of pipe you could end up with water in it after blowing out the lines since residual water could drain and collect in that low section, freeze and cause an issue.

Larry

That could only be an issue if you don’t blow the lines out properly. I did an experiment a few years back for sceptical friend to show him how well it works. I took a 100’ coil of clear fuel hose and hooked to to tap, then with it standing vertically hooked it to the compressor with the regulator set to 50 psi. There wasn’t a drop left in the line.

The issue arises when someone uses a very small compressor that can’t maintain the required pressure for very long, or just doesn’t perform the task correctly.

JoshuaH wrote:
Thanks. We like to camp off grid in the winter, after pricing RV antifreeze I got to thinking I'm going to be spending a lot of money each time we go, would save some money to just blow out the lines.

That makes it sound like you think you’re going to put water back in the system each time you use it during the winter. That is a VERY dangerous proposition. You will have a lot of lines in places you can’t heat enough to prevent freezing.