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Trying to find a way to pass an AC condensation pipe outside

Author: sum (FL)

I have an AC air handler in one of the closets, and it has a Diversitech condensate pump that looks like a shoe box, has a float switch inside it and pumps the water into a copper line that goes up to the attic and out.

Once in a while the pump fails and floods the closet. It is supposed to have a kill switch that shuts off the AC when it fails but that fails too, or it kills the AC after it flooded 2" of water into the closet.

Here is a floor plan of the closet, it is adjoining a bathroom, then the exterior wall.

The north wall of the closet is the common wall to the bathroom. The other side of that is an old 1950s cast iron tub.

I am wondering, these cast iron tubs, the inside edge of it where the bottom is narrower than the top, is that space clear all the way across? Is there any "web" in between?

I am thinking of drilling a hole on the closet/bathroom wall right above the baseboard. Then drill a hole in the same spot may be 1/2" lower on the exterior block wall, and see if a 3/4" PVC pipe can be passed from the outside to the closet through those two holes by weaving through the void space at the bottom right of the tub. In the first picture I showed the path I am thinking in orange color.

Is that void space all the way clear?

Edited 2 times.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: Fixitangel (NC) Hard to tell from this end. Drill a peep hole and have a look. Or use your glasses: There sould be a void space there, fishing a 3/4 pvc pipe in there may be tricky. They put studs inside walls, that can mess up the best of plans. Good luck. Edited 2 times.

Re: Trying to find a way to pass an AC condensation pipe outside

Author: WC (VA)

My daughter had the same problem you have except her equipment was located in the attic. Where the condensate water was pumped out thru the roof, rain water was able to leak past - run down the side of the discharge piping (tubing) - and fill the condensate pan and overflow.

To guard against any unexpected overflows, install a battery operated water alarm costing about $10 in your condensate pan. There are many types available. Get one with wire sensors attached. Mount the sensors on inside of pan at a higher than the "normal" high level. If the condensate pump fails etc. the higher water level will trigger the sensors and you will be warned to take action. You can mount the actual alarm several feet away (other side of wall etc) with the wire running to the pan.

These cheap alarms can be very useful for hot water heaters, wash machines, sump pumps etc.

Edited 1 times.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: steve (CA) I've always seen that space open from end to end.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: packy 99.99% it is wide open under there.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: sum (FL) Fixitangel, the interior wall is shown in brown color to the right of the intended pathways, so studs should be there. I could open the plaster wall and drill holes on each stud and I am trying to avoid that by stealing the space under the skirt of the tub on the inside.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: sum (FL) Thanks, that could be another option. I will check into it as a backup if my plan of eliminating that pump fails.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: johnjh2o (FL) I had the same setup in a rental house we own. Did the same thing. Worked out great. John

Re: Trying to find a way to pass an AC condensation pipe outside
Author: sum (FL) Looks like time to drill some holes to investigate!

Re: Trying to find a way to pass an AC condensation pipe outside
Author: Lee (NJ) Hey Sum: Keep us posted. This seems interesting. I would like to know how it turned out! I always read your posts they are interesting. I admire that you are not afraid to give things a try. Thanks

Re: Trying to find a way to pass an AC condensation pipe outside
Author: HelpMePlumb (FL) I've taken out many tubs and discovered AC condensate lines tucked behind there, among other things. Like old newspapers, steel beer cans, old toys that weren't made in China...

Re: Trying to find a way to pass an AC condensation pipe outside
Author: hj It is done quite frequently. Just stay far enough away from the corners to avoid the studs, and/or backing plates. Edited 1 times.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: joe plumber (NE) I just finished doing one like this .I cut large enough holes in the walls to pass a tapered 5 foot 2 x 4 through the openings with the pipe fastened to the tapered part to give the pipe some grade so it doesn't plug.If the pipe plugs ,you are still going to have a flood in the room where the unit is located .I realize every job is different ,but it worked for me .

Re: Trying to find a way to pass an AC condensation pipe outside
Author: mr leak (CA) You should have room to install a 3/4 inch line at the base of the tub. These tubs have room because there is a taper and do not drop perfectly vertically. Let me know

Re: Trying to find a way to pass an AC condensation pipe outside
Author: Fixitangel (NC) Sum, come to think of it, my tub has a tapered bottom, and I could pass a 1" pvc pipe thru that void, close to the floor, if I needed to. Should be do-able. May I ask what kind of program you use to make your illustrations? That's a cool tool. Thanks.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: Lee (NJ) Sum: That is a real cool application you use for your illustrations. I too want to know what software application or tool you use for doing the drawings posted here? Thank you.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: sum (FL) Fixitangel & Lee I used a CAD program like AutoCAD. Thanks! I think Google Sketchup is free and it can do most of these simple 2D sketches. Edited 2 times.

Re: Trying to find a way to pass an AC condensation pipe outside

Author: sum (FL)

OK some progress.

I drilled a 3" hole on the bottom of the closet wall, right above the baseboard to the far right.

I then stick a 3/4" PVC pipe in. I was able to go pretty far.

See where I marked on the pipe a blue mark?

I then pulled the pipe out and lay it on the east side of that interior wall (the one to the right of the tub), and the blue mark is about 8" shy. Since the door jamb there in the closet is 4", I am missing 4-6 inches somewhere at the end.

But it seems I do have a straight shot. Next thing is to drill from the other end. I need a bit big enough to drill pass a 3/4" pipe.

Edited 2 times.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: hj quote; my tub has a tapered bottom, and I could pass a 1" pvc pipe thru that void, close to the floor, if I needed to. Should be do-able. 1. You have a 2x4 plate at either end you would have to pass over 2. The tub, at the drain end, is NOT 1 1/2" above the floor and even if it were, it would not give enough room for the drain to slope towards the other end

Re: Trying to find a way to pass an AC condensation pipe outside

Author: sum (FL)

That's why I drilled the hole above the baseboard.

But hj you mentoned bottom plate I wonder if that's what I am hitting on the far end. That would account for the missing 4" I am "short" on the reach. I assumed the far end would be just blocks and furring strips but could they have framed in a 2x4 wall below the tub or some reason to have a bottom plate there and my pipe is hitting that.

If so I can bounce the pipe up and down and see if it will get further.

Re: Trying to find a way to pass an AC condensation pipe outside
Author: hj You would have to measure the actual wall thickness to figure out how they framed it. But in any case, you should still be able to shove the pipe 5' plus the thickness of the wall with the hole int it. You could be hitting a "leg" the installer put under the tub to support it.