Blow out fittings icing up!

Discussion in 'Irrigation' started by jcom, Oct 5, 2005.

  1. jcom

    jcom LawnSite Senior Member
    Posts: 791

    A bit of snow and rain and 33 degrees today and could not keep the ice out. I tried antifreeze in the connection fitting but would ice up withing 3-4 minutes. High humidity and cold temps.

    I think I need a drier or something but am asking for input to solve the problem. A lot of customers in the panic mode and my compressor is virtually inoperable.

    Thanks for the help.

    John :rolleyes:
     
  2. Jason Rose

    Jason Rose LawnSite Fanatic
    Posts: 5,858

    How large are your blow out fittings? Sounds more like it's too much volume being pushed thru too small of an orifice. Believe it or not it causes ICE. There is a scientific explination, but I'm not one...

    Usually compressors generate enough heat that the air coming out of the hose, and the hose itself, will get warm, even hot, after a while. But if you have just fired it up the air in the tank is likely at the air temp outside. Maybe run your compressor for a bit to get it warmed up with the hose not hooked to anything and open?

    The only time Iv'e seen an air fitting freeze like that is if I pull the blowoff on my garage compressor, and even then it just gets frosty. But if I did it in near freezing temps with the wetness I bet it'd be worse.
     
  3. bicmudpuppy

    bicmudpuppy LawnSite Silver Member
    Posts: 2,781

    I've never seen this with large volume compressors. Usually the concern is the WARM air. You must be using a smaller unit w/ pressure tank. What pressure are you trying to run? I might suggest a larger and longer run of hose w/ a pressure regulator after the tank. What size fitting are we freezing?
     
  4. jcom

    jcom LawnSite Senior Member
    Posts: 791

    I am using an 18 CFM Dewalt with an 8 h.p. Honda.

    We tie into garden hose fittings for blowouts as a rule. The fitting that is icing up is right off the 1/2" air hose before it is fitted to the female garden hose fitting. Regular Aeroquip fitting I think. Larger hose wouldn't help when the hose fitting is down to 1/2" or maybe evern smaller.

    Thanks again for the input.

    John
     
  5. jcom

    jcom LawnSite Senior Member
    Posts: 791

    Oops,

    I drain the 17 gal. tank every day. But I have left the tank full for an hour or so and then to the next blowout. Would this be problem as to the air temperature?

    Do I need to run the unit full out so that the air is warm before tying into the blowout point?

    John
     
  6. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 48,031

    If you run the compressor at a higher pressure, the unit will get hotter. I would consider trading in the 1/2" air hose for 3/4" garden hose, if you can get the good stuff. Even then some of the cheap boiler drains can ice up, if they have undersized openings.
     
  7. bicmudpuppy

    bicmudpuppy LawnSite Silver Member
    Posts: 2,781

    Just like an airconditioner compressor, when you reduce the pressure, you create cooling (vaporization). I think a secondary regulator (i.e. a tank regulator near max for your compressor, then a pressure regulator for your output) might reduce the amount of freezing. A low volume compressor like your using isn't going to create the heat you get from a high volume compressor. That heat is actually generated by the friction of the air passing through the hose. Only a minimu amount of heat is created by the actual compressor, and the compressor is designed to release that heat anyway. Any chance of insulating and possibly providing heat to the tank and the incomming air? Where's Wetboots when we need him? I'm pretty sure he has used small compressors in the past, and for "late" winterizations too.
    Heat tape run off an inverter around the offending fittings might help, but your going to have to leave the truck running if you pull to many watts with heat tape.
     
  8. PurpHaze

    PurpHaze LawnSite Fanatic
    Posts: 5,496

    Maybe he should build a fire in the front yard and run the hose across that? Would take care of the cold air effect. <JK> :p
     
  9. Wet_Boots

    Wet_Boots LawnSite Fanatic
    Posts: 48,031

    When the air was cold and humid, I would have occasional ice-ups in cheap boiler drains. Sometimes, I would run the system a bit, just to warm up the boiler drains and zone valves. That kept the icing at bay.

    If you installed a pressure regulator where the hose connected to the tank, you could run the compressor at higher (hotter) pressure, and still protect the systems.
     
  10. jcom

    jcom LawnSite Senior Member
    Posts: 791

    The tank pressure is at 140 and I have the outlet regulated to 70psi.

    It is the nipple that connects to the quick connect on the hose that is icing up. From this nipple I adapted to garden hose fitting.

    Thanks again,

    John
     

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