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HVAC Drain Not Flowing

Discussion in 'Homeowners Corner' started by Grasor, Jan 12, 2017.

  1. Grasor

    Grasor New Member

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    Hi all,

    The drain in my HVAC closet where the overflow & condensate lines run from the HVAC & Water Heater has reduced water flow causing it to overflow whenever the heating system runs often. The reason it happens when the gas heat is on is because our whole-house humidifier is running at that time which, by design, has excess water flow that usually goes down the drain.

    I shop vac'd some sediment out of the bottom and used a spool of metal fish tape to probe around the drain. I'd say it went in about 15-20 feet before it hit something that I couldn't get beyond. No idea if that's the blockage or a bend in the pipe.

    I also tried off the shelf pipe clearing enzymes/chemicals at Home Depot. No joy.

    Two questions:

    1) Anyone have an idea on how to best clear the pipe for better flow?
    2) Recommendations on a plumber that won't gouge me for a pipe clearing. Would be very interested in hearing from someone else who had a similar issue.

    Thanks,
    G
     
  2. flynnibus

    flynnibus Well-Known Member Forum Staff

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    Would help to know where your drain goes

    Homes without basements... it usually goes out near ground level or just below to the house exterior

    For homes with sump pits... usually routes to there

    Knowing that you should also predict turns in the pipe
     
  3. Grasor

    Grasor New Member

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    The pipe likely connects to the main sewer line leaving the house. However, this is all under the concrete slab on which the townhouse stands and connects to sewage lines at some point underground. I believe this connection is near the street.
     
  4. flynnibus

    flynnibus Well-Known Member Forum Staff

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    Doubtful... They can't tap into the sewer line directly by plumbing code... they can drain into another fixture draining into the sewer (so it can drain into your sink or shower basin.. but no directly tap into the drain). So it would drain into something above the trap on the drain. Usually on townhomes it drains to lines put into the slab. Look for drains out of the rear of your home near the wall the HVAC is closest too or a bathroom nearby.
     
  5. Grasor

    Grasor New Member

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    ...Yes the main drain line leading to the sewer line in the street. If you want to split hair over terminology then yes I'm referring to the larger pipe all of the water leaves the home from. Now, do you have any recommendations for a reputable plumber?

    G
     
  6. KTdid

    KTdid Well-Known Member

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    Our hot water heater overflow line taps into the AC condensation pipe which is buried under the sod, the length of our back yard.
     
  7. flynnibus

    flynnibus Well-Known Member Forum Staff

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    which I just explained... you are assuming incorrectly. (which would have been info you could have used to work the drain from the other end...) but whatever
     
  8. Grasor

    Grasor New Member

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    Steve - Are you saying the pipe in the concrete I previously described ties into the same wastewater pipe as the rest of the fixtures in the home or that it is a separate pipe entirely that exits the home at some other point? From your initial description it sounds like the former but your second description sounds like the latter.

    I do have a pipe near my AC condenser outside that exits the home. In 9 years I've never seen any water come out of it and it was assumed to be a vent of some kind. In measuring the distance off the common wall of the unit next door between the pipe in the slap of the HVAC closet and this pipe outside they are both about 65" off the wall. So they could be one and the same. The exterior one, however, has a 1 1/4" inside diameter while the one in the house has a 2" inside diameter. That may mean nothing as it could have been reduced for any number of reasons. Another detractor is that the one outside of the house measures (using crude references to the nearby window sill) to be a few inches HIGHER than the floor on the other side of the wall. A plus is I can't get my fish tape to fish more than about 8" in on that side. So might be this pipe? See photo.

    20170114_094630.jpg

    Couldn't get my inspection camera past the bend in the 90 degree elbow of the external pipe and I can't see which direction the fish tape goes in the pipe in the HVAC closet because it has standing water in it but there's room to cut off the exterior elbow and run the camera if need be to see what's blocking the tape. I'm just not 100% that this is the correct pipe yet.
     
  9. signifer

    signifer New Member

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    We're in a Miller and Smith townhouse in Southern Walk and had that drain clog. I went to Home Depot and got a 25' (I think, it may have been 50') snake and ran that down the line. It cleared the clog. Now I flush some hot water from the HW tank down that drain every month or so and it hasn't clogged back up.
     
  10. KTdid

    KTdid Well-Known Member

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    That looks like the condensation drip line for your AC. If not, it could be an emergency drip line for your hot water heater, in which case you would NOT want to see water.
     
  11. Grasor

    Grasor New Member

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    Is that tool this doo-dad available from HD? http://www6.homedepot.com/tool-truc...n_Cleaner_25_x_5_16/SK-R-5-16EIC25/index.html

    KTdid - I think this is the same drain I'm referring to in the HVAC closet. The drip line from the water heater ties in here as well as the AC system drip line and the bypass drain for the whole house humidifier. Not all this stuff runs at the same time obviously so it should handle it. I think I'm going to try snaking it with that power tool and see what turns up.
     
  12. flynnibus

    flynnibus Well-Known Member Forum Staff

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    Your initial effort you assumed the drain line tied into your sewer line where it's not accessible. The drain line will not tie into the main sewage line directly - it will either tie to a fixture that is vented with a trap (like draining into a sink's drain **above** the trap), drain to your sump pit, or drain outside the house. So it will be a seperate line, that terminates into a fixture with a trap... or not into your sewer line at all.

    I'm not familiar with your particular house.. so that's why I have to be a bit 'theory' vs specifics. Since you are a townhome, I assume you have no sump pit.. and you should be able to check any bathrooms or sinks you have on the ground floor which is the only other place it could go.. besides outside the house.

    The line in your photo is the type you'd be after. In our M&S townhome.. the line was ran in nearly a straightline to the rear of the house.. but in our case, the line exited the concrete below the grade level. On others in the row, it was above grade. In my case, the exit below grade caused problems and we ultimately had to dig it and extend out to further in the yard to stop making a swamp at the back of the house.

    Looks like you have a patio there, which hinders any snooping along the wall to check for other drains. You might want to look at some of your neighbor's houses to compare. But it's most likely that drain is the one you seek. Never seeing water is the only question mark.. as during the summer, the A/C drains can produce quite a bit.
     
  13. signifer

    signifer New Member

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    The one I got looked like this one but it wasn't this exact one.; in any event, it was a simple, hand operated thing like this one. I also don't remember how long it was and at the moment it is hiding in the garage. (I put it somewhere that would be easy to find but I can't find it...sigh)
    http://www.homedepot.com/p/RIDGID-Kwik-Spin-41348/203203829
     
    jwf likes this.
  14. Grasor

    Grasor New Member

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    Eureka?

    1.jpg
    2.jpg

    The broken pieces were inside the pipe. So it was either busted through when property was built or at some point it maybe froze and the piece fell in? Big clump of dirt in the way. Concerned that the down flow pipe seems to flow water backwards a bit giving credence to the freezing theory.
     
  15. KTdid

    KTdid Well-Known Member

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    Hmm, do you think is was damaged during the patio install? When you replace the pipe make sure it has a good slope to move the water (unless you already have a pump to move it) . I made a small dry well at the exit point and check it every so often to make sure the condensation is draining properly.
     
  16. flynnibus

    flynnibus Well-Known Member Forum Staff

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    Told ya... exit near foundation :)
     
  17. Grasor

    Grasor New Member

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    Yup!

    KTdid, where abouts is the exit? I repaired the pipe and verified correct slope but pipe filled with water again actually worse then before because now the hole in the middle is gone. I'm more convinced now that the damage was water freezing in the middle possibly from the exit being blocked.

    I installed the patio, but we didn't dig as much as we added base material. The pipe is busted clean through so it was either spiked or something in the middle expanded are my guesses.
     
  18. KTdid

    KTdid Well-Known Member

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    The pipe probably extends 10-15 feet or more - I'd replace the entire pipe since you think there may be another blockage somewhere. Good Spring project.
     
  19. Grasor

    Grasor New Member

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    10-15 feet from wall or another 10-15 from where the broken pipe is pictured?

    Straight out or does it curve?

    Does it go beyond a townhome's rear property line?
     
  20. flynnibus

    flynnibus Well-Known Member Forum Staff

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    Should just be a straight shot out into the yard. Look for where slope might make the exit break the ground level. The ground has probably filled in around the pipe exit
     

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