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Beau_Bo's avatar
Beau_Bo
Explorer
Dec 06, 2016

130 psi compressor for winterizing?

Hi - looking at at a Viair 400p compressor to carry al0ng for airing up tires, etc. It is capable of putting out 130 psi and 2.3cfm which is desirable for filling up the truck tires. Another use I am looking at for it is to blow down my camper water lines for winterization. I would approach this cautiously with several faucets open before turning on the air, just wondering if even with faucets open this might be too great a volume/psi input and it might over pressurize my water system. Thoughts?

28 Replies

  • Get a little regulator to put in the line b4 the camper and set it for abt. 40 psi.
  • I thought I'd try blowing down rather than antifreeze this year. What I learned:

    A 3 gal HF pancake compressor ain't really up to the job. Needed to get done BEFORE spring :)

    Bigger the tank the better.
  • I have been using an inexpensive 12 volt compressor to winterize my rig for 20+ years - same compressor that I use to inflate my 65 PSI tires (ain't fast but it works fine). Anecdotal evidence that you don't need "bigger" to blow water out of RV water lines.
  • I think I'd prefer a tanked compressor for that job. It's about blowing a lot of air through the lines, not pressurizing them.
  • RoyB's avatar
    RoyB
    Explorer II
    If that VIAIR model is a tankless type it will takes longer to build up pressure each time you turn it...

    My 12VDC Air Compressor is a tankless type and I have plenty of time to turn it on and walk inside my POPUP trailer and open a water spigot...

    I have the older MV50 Tankless 12VDC Air Compressor.

    Roy Ken
  • The simplest and best solution in my opinion is to get an air pressure regulator for use when winterizing. Harbor Freight (among other many places) sells small ones that would be perfectly sufficient for this use for a few dollars. You don't need anything too precise or consistent for this use.

    Always leaving a tap or valve open should prevent any great pressure buildup in the plumbing lines. They theoretically ought to be able to withstand 130 psi, though any slugs of water that are being blown along could produce much higher stresses due to their inertia when they hit constrictions etc.
  • It should work if you do it very cautiously. The Viair, while it will put out high pressure, is still a low volume air compressor.

    Open all of your faucets before turning on the Viair. Then start the compressor, let it run for a moment until water and air are blowing out the faucets. Let it run fur a while.

    After about 5 minutes, shut one or two of the faucets. Watch how hard the air is blowing out of the rest of the faucets. You want to judge that the air coming out of the faucets is no more than 45PSI that can hurt the plumbing.

    As I think about this more, the Viair being a high pressure but low volume compressor, it might not put out enough air volume to blow out water lines?

    Whatever you do, don't shut all of the valves. If all the valves are closed it will develop enough air pressure to rupture things.

    Bill
  • I would not want that much pressure in my water lines, especially the water pump. If yo could dial it down to 45 psi, that would be fine.