Question for "Blow Out the Water Line" gurus

KJINTF wrote:
Stopped blowing out the Rigs lines many years ago - It now stays in a heated barn

100% agree with Wyo Traveler every year we blow out the 140 or so sprinkler heads in the lawn and the several hundred feet of under ground pipes never an issue with freezing even in Montana.

Never could understand putting that pink stuff in anything

Except drain lines!!!

I have blown out the water lines, etc. in my FWs for the past 15 or more years with only one problem. Something happened to the main line and it split right under the shower pan. Pulled up the pan, found the split, called a dealer and they were able to get to it that morning. I might have forgotten to open the low point drain lines. Pulled it down there, waited around and an hour later it was fixed. They didn't put the pan back in, but since I took it out, I put it back in. That is the only problem I have had while blowing out the lines with compressed air. I use a 6 gallon compressor and now set the pressure at 50. Maybe I should go back up with my pressure.

How effective is opening low point drain line along with all the valves?

philh wrote:
How effective is opening low point drain line along with all the valves?

If (and it's a really, really big if) the RV is designed such that all the water lines slope towards the low point drain and have no dips or loops anywhere, and it were level when you did the draining, then it would be perfectly effective.

In practice, RVs are not generally so constructed, and this doesn't work at all reliably.

I have seen vacation homes with plumbing designed such that it could be drained completely by gravity, and it works quite nicely there. It's a lot easier to avoid dips in the plumbing when you're dealing with hard copper pipes and a structure that stays level.

After opening the low point drains in our coach, I find that I get little more than droplets of water out when I blow the lines.

I guess Safari did a proper job of designing and building the plumbing system.

I could probably get by without blowing, and relying solely on the low point drains, but blowing only takes a couple of minutes and gives extra assurance that the lines are sufficiently water-free.

Wayne

I get a flood out of my low points, but don't forget to drain the water heater and protect the traps.
The outdoor shower did get me one year darn it.:o

I've found I can get more water out of the lines before blowing the lines out if I use the levelers to tilt the coach to the left while draining.

Dutch_12078 wrote:
I've found I can get more water out of the lines before blowing the lines out if I use the levelers to tilt the coach to the left while draining.

Also, I do this to get as much water out of the Fresh tank. I lean the RV up on the opposite side of the fresh water drain. Doug

I have been using the low point drains only for a few years now. I raise the front a little Nary a problem yet. It has been pretty darn cold here in the winter. Of course pink in the traps and some in the tanks so it rest next to the valves as i close them. May leave them open this year for a day or two just to make sure all in gone. as of right now the fresh water tank is drained with the rest of the system getting the treatment later today.

KJINTF wrote:


Never could understand putting that pink stuff in anything

And many don't realize that there are two types of RV antifreeze. One is propylene glycol based and the other is ethanol based and is considerably cheaper which is why most vendors flog it. The cheap stuff will evaporate (toilet bowl), is flammable, will taint potable water systems (bad taste & odor) and can damage seals. The good stuff doesn't have the cons of the cheap stuff and is non-toxic and will lubricate seals and valves. If you shop around enough, you can find the PG based version at a decent price. I've found some antifreeze containers that don't list the contents and even if they do, it's often in small print and you have to look for it.

What I don't understand is why people will use the ethanol based antifreeze no problem but will come up with every reason why not to use air. As mentioned here, the air method must be done correctly.

We are on the air side of the fence. I use air to blow out the hot/cold low point drains and don't rely on gravity. I go between all faucets, valves & drain points several times until there is absolutely no hint of water. We don't use the FW tank so no worries there although I recently discovered that the FW tank is filling off city water and the pump check valve must be faulty.