Page 1 of 2 12 LastLast
Results 1 to 13 of 16
  1. #1
    Join Date
    May 2018
    Posts
    67
    Post Likes

    AC Condensate Trap on Positive Preassure side?

    I posted previously about my year old Trane S9V2 not going into 2nd stage correctly in the new heating season (no problems last winter). The problem ended up being that the AC and Furnace condensate line were tied together and was causing back pressure not allowing 2nd stage to operate correctly.

    Tech was out this week and separated the lines. I asked him about the need for a trap on the AC condensate side (per the info I got on this site) and he said it wasn’t needed as it is under positive pressure.

    Here are my questions:

    (1) Besides efficiency loss, is there any good reason to put a trap on AC condensate line that is under positive pressure?

    (2) wouldn’t a trap on AC side under positive pressure dry up anyway over the summer? So what’s the point

    (3) can I just keep the PVC service cap off and allow the little bit or air that escapes to go up into the furnace room instead of down into the the drain? Will this have any effect on proper drainage? Or does this basically act as a vent to allow water to drain even better?

    (4) I noticed the tech didn’t put a service cap on furnace drain. Is this acting as a vent? Or did he forget?

    Thanks.

    Here are the pics (with service cap and without)
    Attached Images Attached Images   

  2. #2
    Join Date
    Dec 2005
    Location
    Cincinnati, Oh
    Posts
    7,131
    Post Likes
    The cap on the coil is for cleaning out.

    The lack of a cap on the furnace is acting as a vent.
    "Better tell the sandman to stay away, because we're gonna be workin on this one all night."

    "Dude, you need more than 2 wires to a condenser to run a 2 stage heatpump."

    "Just get it done son."

    Dad adjusted

  3. #3
    Join Date
    May 2018
    Posts
    67
    Post Likes
    Thread Starter
    Thanks—so is it ok to just leave the AC cap off? Wouldn’t that also act like a vent?

  4. #4
    Join Date
    Jul 2011
    Location
    DFW, TX.
    Posts
    1,345
    Post Likes
    Maybe its just me, but it looks like standing water in the water heater drip pan.???

    Sent from my LG-G710 using Tapatalk

  5. #5
    Join Date
    Mar 2018
    Location
    Chico, Ca #StateofJefferson
    Posts
    1,351
    Post Likes
    A trap on the positive pressure coil is "not necessary" for drainage but is recommended if it drains outside of the conditioned space as that will increase the infiltration rate as it depressurizes the building. As long as the ac is running its constantly filling up the trap, the trap can dry out during winter if you have those crappy preformed traps, I prefer to build my own for ease of cleaning

  6. #6
    Join Date
    Dec 2007
    Posts
    9,118
    Post Likes
    https://www.trane.com/content/dam/Tr...N_11112016.pdf


    Still not to mfr's instructions.

    I thought I remembered some funky requirements for the condensate.
    The Food Stamp Program, administered by the U.S. Department of Agriculture, is proud to be distributing the greatest amount of free meals and stamps EVER.
    Meanwhile, the National Park Service, administered by the U.S. Department of the Interior, asks us to "Please Do Not Feed the Animals". Their stated reason for this policy "... the animals become dependent on handouts and will not learn to take care of themselves."
    from an excerpt by Paul Jacob in Sun City, AZ

  7. #7
    Join Date
    Mar 2018
    Location
    Chico, Ca #StateofJefferson
    Posts
    1,351
    Post Likes
    Is that a carbon monoxide monitor laying on the condensate pipes? You've got no auxiliary drain line or overflow switch to shut down the ac when the drain line clogs, that will be a costly repair. Ask your hvac contractor to wire in a float switch, very cheap protection

  8. #8
    Join Date
    May 2018
    Posts
    67
    Post Likes
    Thread Starter
    Quote Originally Posted by pacnw View Post
    https://www.trane.com/content/dam/Tr...N_11112016.pdf


    Still not to mfr's instructions.

    I thought I remembered some funky requirements for the condensate.
    I read the manual—I don’t see any mention of a trap...what part do you think is wrong?

  9. #9
    Join Date
    May 2018
    Posts
    67
    Post Likes
    Thread Starter
    Quote Originally Posted by CEAS-AC-TECH View Post
    Maybe its just me, but it looks like standing water in the water heater drip pan.???

    Sent from my LG-G710 using Tapatalk
    No standing water—I actually have a water alarm in that pan that would go off it it was leaking.

  10. Likes CEAS-AC-TECH liked this post
  11. #10
    Join Date
    May 2018
    Posts
    67
    Post Likes
    Thread Starter
    Quote Originally Posted by Makeitcold View Post
    Is that a carbon monoxide monitor laying on the condensate pipes? You've got no auxiliary drain line or overflow switch to shut down the ac when the drain line clogs, that will be a costly repair. Ask your hvac contractor to wire in a float switch, very cheap protection
    Yes, it’s a CO detector.

    Do you have an image of this auxiliary drain line? So like a pan under the line in case it leaks?

  12. #11
    Join Date
    Feb 2010
    Location
    Metro Atlanta, GA
    Posts
    554
    Post Likes
    Quote Originally Posted by DVA79 View Post
    Yes, it’s a CO detector.

    Do you have an image of this auxiliary drain line? So like a pan under the line in case it leaks?
    The auxiliary drain is the one that's plugged on the evaporator coil. Since you don't have a secondary drain pan it would be wise to either pipe that secondary drain to the floor drain or add a safety switch so the unit shuts down in case of a clogged primary drain. If the mechanical room is in a finished basement I would suggest adding a wet switch to the system to shut it down when that floor drain backs up.

  13. #12
    Join Date
    Mar 2018
    Location
    Chico, Ca #StateofJefferson
    Posts
    1,351
    Post Likes
    Look on our wall of fame forum to get a good idea of what we mean, its conveniently next to the wall of shame forum. Flyersfan makes a great point I forgot about the main drain backing up. Had this happen to a customer 2 years ago in the finished basement while they were on vacation in Europe for 3 weeks, that was a powerful smell in the middle of July

  14. #13
    Join Date
    May 2018
    Posts
    67
    Post Likes
    Thread Starter
    Quote Originally Posted by Makeitcold View Post
    Look on our wall of fame forum to get a good idea of what we mean, its conveniently next to the wall of shame forum. Flyersfan makes a great point I forgot about the main drain backing up. Had this happen to a customer 2 years ago in the finished basement while they were on vacation in Europe for 3 weeks, that was a powerful smell in the middle of July
    Is this what we are talking about?
    https://rectorseal.com/product/safe-t-switch-ss1/

    Looks like a genius idea. So I would just screw that into the secondary drain and then connect the wires to the AC terminal?

    Or would I be better served just running another line to the floor drain?

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
  •