Page 1 of 2 12 LastLast
Results 1 to 13 of 17
  1. #1
    Join Date
    Sep 2009
    Location
    Hampton, GA
    Posts
    571

    What is required to modify when using 407C and 404A as drop-in for R-22

    Name:  WP_000546.jpg
Views: 484
Size:  58.6 KBHFC-407C and HFC-404A if they are used a drop-in replacement for R-22. Other then maybe changing the compressor oil out, are there any other requirements? Is this a cost effective then to buy R-22 currently, which may go up in price later on? I was just wondering about this and I wanted feedback from you guys.
    wHen I diE I hOpe gOd haS mErcy oN my SiNful LifE

  2. #2
    Join Date
    Jun 2012
    Posts
    116
    404a would probably require a new TXV at the least

  3. #3
    Join Date
    Sep 2002
    Location
    Virginia
    Posts
    3,179
    404 is just as expensive as 22

  4. #4
    Join Date
    Nov 2012
    Location
    Tahlequah OK
    Posts
    131
    Why would want to use 404? It is really not a good replacement for 22 in AC system. I have never heard of using 404 in place of 22. 404 is always used in low temp systems.

  5. #5
    Join Date
    Dec 2007
    Location
    Chandler AZ
    Posts
    168
    Quote Originally Posted by welling service View Post
    Why would want to use 404? It is really not a good replacement for 22 in AC system. I have never heard of using 404 in place of 22. 404 is always used in low temp systems.
    A lot of med temp reach in use 404a

  6. #6
    Join Date
    Aug 2010
    Location
    Northern Cali
    Posts
    72
    I pay alot more for 22 than I do 404. Never heard of dropping in 404 to replace 22.

  7. #7
    Join Date
    Sep 2009
    Location
    Hampton, GA
    Posts
    571
    Quote Originally Posted by MAC AIR View Post
    I pay alot more for 22 than I do 404. Never heard of dropping in 404 to replace 22.
    I never heard of it either, loll but it says it in my textbook. I just wondering what you folks thought about it.

  8. #8
    Join Date
    Jul 2010
    Location
    Eastern Kentucky
    Posts
    55
    hmmmmm... next junk R-22 unit you have, dump some 404 in it and report your findings lol.

  9. #9
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,671
    With a metering device change, r-22 to 404a is possible.

    R404a is an excellent MT refrigerant. Don't think that it isn't. I haven't seen it in AC applications, though.

    Besides oil changes and MD changes/modifications, you'll also want to replace any elastomeric seal on the system. The change from R-22 to 404/407 causes the seals to shrink back to a normal size and will VERY often cause VERY LARGE leaks.

  10. #10
    Join Date
    Jan 2004
    Location
    Lancaster PA
    Posts
    68,104
    R404A would be suitable to replace R22 in a refrigeration application, but not a high temp one such as comfort cooling on an air to air system.
    Contractor locator map

    How-to-apply-for-Professional

    How many times must one fix something before it is fixed?

  11. #11
    Join Date
    Jun 2003
    Location
    Chicago, IL
    Posts
    4,435
    That is a weird book you have In the pic. Neither of the refrigerants that are listed as "drop ins" actually are.

    A "drop in" requires no modification to the system. Hot Shot is a drop in for r-12.

    To replace R-22 with 404 would require at a minimum new TXVs, oil, and seals. It also has a pretty large capacity loss.

  12. #12
    Join Date
    Sep 2009
    Location
    Hampton, GA
    Posts
    571
    Quote Originally Posted by beenthere View Post
    R404A would be suitable to replace R22 in a refrigeration application, but not a high temp one such as comfort cooling on an air to air system.
    What type of refrigeration application? And also when you say comfort cooling , you mean just plain AC units ? Thanks for the replies.

  13. #13
    Join Date
    Sep 2009
    Location
    Hampton, GA
    Posts
    571
    Quote Originally Posted by craig1 View Post
    That is a weird book you have In the pic. Neither of the refrigerants that are listed as "drop ins" actually are.

    A "drop in" requires no modification to the system. Hot Shot is a drop in for r-12.

    To replace R-22 with 404 would require at a minimum new TXVs, oil, and seals. It also has a pretty large capacity loss.
    It is my school book. 'HVAC' NCCER Contren Learning Series . Currently in Level 3 book. One more to go afterward!

    Well, thats why I asked the question here to get feedback from folks on the field. I also understood the "drop-in" as just charging the unit with replacement refrigerant and no need to modify. But as I continued to read the book, it said to change the oil in the compressor. And the pro's here also said other things like txv and some seals.

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