Page 1 of 2 12 LastLast
Results 1 to 13 of 15
  1. #1

    Question 440 Vapor Charge: What does it do to the Liquid?

    Customer received the unit with major leak, which i fixed. I used to test leak and recharged with vapor side of 404 tank, like a dummy... Then, I had evap coils freezing up and fluctuating head pressure so i replaced the expansion valve. I realize charging with vapor may have been my problem all along. Alright, it was dumb, but i had not worked with 404 before... Once i realized the mistake, after replacing expansion valve, i vac'd the unit, then recharged with liquid from the same tank i had pulled the vapor from. Now, the head pressure is shooting to 450 and pressure relief valve land like an obstruction in the line. Could this be related to the usage of the same tank?! Or, would it cause the unit to do something else? Doesn't the new sympton sound like an obstruction?

    Please help and sound off!
    Just don't flame me too much, though, y'all!

    Billy Wilson
    Hattiesburg, MS

  2. #2
    Join Date
    Jan 2008
    Location
    In the work truck
    Posts
    3,000
    i hope you have some time until that unit needs to be fixed. you need to apply for pro status before we can give you real technical info. what is you superheat and subcooling?? and to understand better you pulled the 404 into a tank... than used the same refer and charged the system again?

  3. #3
    Join Date
    Feb 2001
    Location
    Arizona
    Posts
    5,460
    Quote Originally Posted by Pascone10 View Post
    i hope you have some time until that unit needs to be fixed. you need to apply for pro status before we can give you real technical info. what is you superheat and subcooling?? and to understand better you pulled the 404 into a tank... than used the same refer and charged the system again?
    What's wrong with that?
    Other than charging back to the unit from the VAPOR side of the tank.
    Maybe he just needs to recover back to the same tank and recharge again from liquid.

    If that's not the problem with the high pressure, maybe he accidentally brazed the inlet side of the TXV shut with sil-floss or something.
    True Heavy Metal Geek

  4. #4
    Join Date
    Oct 2007
    Location
    Richmond, VA
    Posts
    362

    Confused more info

    Need more info before we can help. What, exactly, are you working on. I/M, Refrigerator, freezer? If possible, need make, model serial numbers. Help us to help you.:

    Bill

  5. #5
    Join Date
    Jan 2008
    Location
    In the work truck
    Posts
    3,000
    Quote Originally Posted by PaysonHVAC View Post
    What's wrong with that?
    Other than charging back to the unit from the VAPOR side of the tank.
    Maybe he just needs to recover back to the same tank and recharge again from liquid.

    If that's not the problem with the high pressure, maybe he accidentally brazed the inlet side of the TXV shut with sil-floss or something.
    nothing yet.. as long as we did not get air and/or moisture mixed with the refrigerant when he recovered. just trying to get more info

  6. #6
    Join Date
    Feb 2001
    Location
    Arizona
    Posts
    5,460
    Quote Originally Posted by Pascone10 View Post
    nothing yet.. as long as we did not get air and/or moisture mixed with the refrigerant when he recovered. just trying to get more info

    True.

    And so far we don't know if he's working on a 12 ounch reach in system, a ice machine, or a Bohn Beacon Walk IN LOL!
    True Heavy Metal Geek

  7. #7
    Join Date
    Sep 2007
    Location
    NH
    Posts
    1,148
    I would say that Tank is now JUNK..

    You have made your own little cocktail there. Epecially if you charged more than a pound or so with vapor.

    If you still have that gas that you recoverd the first time you can add the rest of your 404 tank and the remaining gas in the system in to the tank and you should have 404 again.

    The only time you can charge as a vapor is it you add the whole tank to the system....

    I'm guessing your not working on something that big.
    Last edited by Dchappa21; 09-10-2008 at 06:45 PM.

  8. #8
    Join Date
    Mar 2007
    Location
    NW AR
    Posts
    2,478
    Quote Originally Posted by newyokel View Post
    Customer received the unit with major leak, which i fixed. I used to test leak and recharged with vapor side of 404 tank, like a dummy... Then, I had evap coils freezing up and fluctuating head pressure so i replaced the expansion valve. I realize charging with vapor may have been my problem all along. Alright, it was dumb, but i had not worked with 404 before... Once i realized the mistake, after replacing expansion valve, i vac'd the unit, then recharged with liquid from the same tank i had pulled the vapor from. Now, the head pressure is shooting to 450 and pressure relief valve land like an obstruction in the line. Could this be related to the usage of the same tank?! Or, would it cause the unit to do something else? Doesn't the new sympton sound like an obstruction?

    Please help and sound off!
    Just don't flame me too much, though, y'all!

    Billy Wilson
    Hattiesburg, MS

    I have made that stupid mistake before. Sounds like your talking about your jug of 404 and not a recovery tank. If so, and you only had to use x amount of ounces, your jug of 404 should be okay until the liquid level in it gets low, then Id despose if it. I dont believe your jug is the problem.

    Your problem sounds more like an overcharge or non-condensibles than a restriction. How deep of a vacuum did you pull? Did you weigh the 404 in?
    We cant get into alot of detail cuz of the rules. Ive probably already said too much. Sorry mods.

  9. #9
    Unless you have a restriction in the discharge line or middle of the condenser or you have over charged the system, your head psi wont go above 300lbs. You have non-condensables in the system, "AIR". Recover ref, and then use a VACUME PUMP, pull system down to 29" and then recharge with weighed in liquid 404-A. Use a new bottle. Then you have ruled out all the possible ref, questions. and should be good.

  10. #10
    Join Date
    Aug 2006
    Location
    st.petersburg,fl
    Posts
    803

    Lightbulb Hope this Helps

    The amount that 404a fractionates is so small. That you might as well say that it does not fractionate at all...


    Oh ya, and it sounds like you have a restriction....


    Hope this helps
    Isn't sanity just a one-trick pony anyway? I mean, all you get is that one trick, rational thinking, but when you're good and crazy, well, the sky's the limit!

  11. #11
    Join Date
    Aug 2008
    Posts
    20
    Your tank is fine. If it was that big a deal you'd have to pull the entire charge on a 404 system every time you have a leak on the suction side. But we don't. Vac it and charge it properly, then go looking for your cause (if it wasn't non condensables).

  12. #12
    Join Date
    Sep 2008
    Location
    Southwestern Ontario
    Posts
    99
    A good rule of thumb for the future......any refrigerant number that starts with a 4 is a blend and needs to be charged as liquid.

  13. #13
    Join Date
    Jul 2007
    Location
    regina saskatchewan
    Posts
    257
    Quote Originally Posted by dblrye View Post
    A good rule of thumb for the future......any refrigerant number that starts with a 4 is a blend and needs to be charged as liquid.
    There are some exceptions.422D is one.
    Artificial Intelligence is no match for Natural Stupidity

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event