Condensation line in attic / AC air handler

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mancich
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Condensation line in attic / AC air handler

Post by mancich »

Hello all,

We have two zone A/C with an attic air handler. The condensation PVC pipe coming off it is impossible to pitch properly because of various obstructions, and we have had a couple of incidents over the last 18 years where water remains in the line in the Fall, freezes, causes a crack, then leaks when the A/C is turned on the following late Spring. I am thinking of getting a condensate pump and running a clear tube from the pump to the existing hole where the pvc exits the house. I would put the pump in a large pan, next to the air handler with a water sensor for redundancy. Any POV on if this is a good solution? We have a Little Giant pump for the basement air handler and so far it has worked well.

Thanks.
Liberty1100
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Re: Condensation line in attic / AC air handler

Post by Liberty1100 »

The condensate pump sounds like the best idea. It’s a good idea to get that water sensor too.
wfrobinette
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Re: Condensation line in attic / AC air handler

Post by wfrobinette »

mancich wrote: Fri May 29, 2020 1:29 pm Hello all,

We have two zone A/C with an attic air handler. The condensation PVC pipe coming off it is impossible to pitch properly because of various obstructions, and we have had a couple of incidents over the last 18 years where water remains in the line in the Fall, freezes, causes a crack, then leaks when the A/C is turned on the following late Spring. I am thinking of getting a condensate pump and running a clear tube from the pump to the existing hole where the pvc exits the house. I would put the pump in a large pan, next to the air handler with a water sensor for redundancy. Any POV on if this is a good solution? We have a Little Giant pump for the basement air handler and so far it has worked well.

Thanks.
Good idea! I had an HVAC in the basement and that was the solution.
crefwatch
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Re: Condensation line in attic / AC air handler

Post by crefwatch »

Naturally, the condensate pump output will also be subject to freezing. I use a vinyl tube for my basement dehumidifier (no freeze issues), and because a vinyl tube can never be as straight at a PVC pipe, it tends to collect some water in low swag points. Besides freezing in your attic, this could potentially produce clogging from mold or lichen in the wet areas.

Condensate pumps can be expensive, but last for a long time. Their check-valves may not last as long as the pump. This may be less important for a mostly downhill run. My condensate pump also has contacts for an over-height water reservoir alarm, but your spill detector alarm is a good idea. Note that you can buy a water heater leak-pan that is punched for a (gravity) drain pipe, if that works out for the location.

I think you already understand that dust, insects, mice, mold, and mildew can all occur in condensate lines. Especially because venting is essential. Because I turn off the dehumidifier each fall, I verify function of the pump, all the way to the sill of the house, every summer. There is no substitute for vigilance. What is the highest temperature in the attic? Check the pump specs.
ponyboy
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Re: Condensation line in attic / AC air handler

Post by ponyboy »

Just remember, the condensation pumps are noisy. You'll hear it each time it runs, which is only for 2 or 3 seconds. We have to use one in our basement. We can hear it when we're on the first floor, lucky for us, all bedrooms are on 2nd floor. I wouldnt want to try to sleep with it turning off/on all the time if it was above me.

If I were you, When it gets cold and you'll no longer be using your ac, go up to the attic once or twice a year, disconnect the line from the handler so you can tilt it and drain it out. Its not difficult, but will require you to do a tiny fraction of work/effort. Much better than a noisy pump running a hundred times each day/night.
illumination
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Re: Condensation line in attic / AC air handler

Post by illumination »

FWIW, I have had problems with this on my AC lines despite there not being any problems with the pitch of the drain pipe. It just gets clogged with some moldish looking debris and it's part of my maintenance regime to clear them out. I take a shop vac with a cone shaped attachment and suck it out from the outside time to time. I also put a threaded PVC detachable coupling to easily get at both side of it.
I also have a Gallo gun that uses CO2 cartridges, but that's usually overkill. I could just see a condensation pump being another point of failure, might be easier to just spend a few minutes a season clearing out what you have now.

On those water sensors that kill your AC if the water level gets too high, I have had nothing but problems with those. My insurance company mandated them, the first week the AC went on they tripped and had forgotten about them, was chasing my tail trying to figure out why my AC wasn't working. I have some relatives and there's did the same thing. All of them had to be disconnected because of all the times they would shut down the systems. Maybe it was the brand, but they were "professionally" installed.
Designairohio
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Re: Condensation line in attic / AC air handler

Post by Designairohio »

illumination wrote: Fri May 29, 2020 4:02 pm FWIW, I have had problems with this on my AC lines despite there not being any problems with the pitch of the drain pipe. It just gets clogged with some moldish looking debris and it's part of my maintenance regime to clear them out. I take a shop vac with a cone shaped attachment and suck it out from the outside time to time. I also put a threaded PVC detachable coupling to easily get at both side of it.
I also have a Gallo gun that uses CO2 cartridges, but that's usually overkill. I could just see a condensation pump being another point of failure, might be easier to just spend a few minutes a season clearing out what you have now.

On those water sensors that kill your AC if the water level gets too high, I have had nothing but problems with those. My insurance company mandated them, the first week the AC went on they tripped Tn and had forgotten about them, was chasing my tail trying to figure out why my AC wasn't working. I have some relatives and there's did the same thing. All of them had to be disconnected because of all the times they would shut down the systems. Maybe it was the brand, but they were "professionally" installed.
+1 on the Gallo Gun bow the Line out at the end of the season, that along with an occasional shot of bleach to keep on clean
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4nursebee
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Re: Condensation line in attic / AC air handler

Post by 4nursebee »

Change the pvc to pex, it freezes without bursting

Y’all need to use hvac drain tabs
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WildBill
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Re: Condensation line in attic / AC air handler

Post by WildBill »

Howdy

One item of cheap preventive maintenance is to keep a bottle of bleach in the attic and pour some bleach into the lines every time you change the furnace/AC filters in the attic. Since I started doing this my previous problems with the drain lines plugging have gone away.

Good luck

W B
"Through chances various, through all vicissitudes, we make our way." Virgil, The Aeneid
kabob
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Re: Condensation line in attic / AC air handler

Post by kabob »

Had a townhouse condo in Florida that had the air handler in the attic with an emergency condensation overflow drain that emptied thru the top(ceiling) of a nearby bath/shower below it! It's a quite common solution in Fla to prevent ceiling damage from a clogged condensation line that's used nearly yr round. Whenever the tub/shower is wet without being used - it's time get the condensation line cleaned/blown out! (and does no harm/damage)
There's also a little float/control-shutoff/alarm device that can put into the pan/line that can be used also...
But the emergency overflow thru nearby ceiling into tub/shower works Great!
Last edited by kabob on Sat May 30, 2020 5:32 am, edited 1 time in total.
likegarden
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Re: Condensation line in attic / AC air handler

Post by likegarden »

We live in a house with an AC Air Handler in the attic above the second floor. We had overflowing of the pan under the air handler, with the installer afterwards raising the air handler to pitch the drain pipe to the outside properly. No problem since. Now we should have the installer come to do his annual check of the AC and that drain pipe, but with an unknown virus risk entering our home is risky. So we wait and hope the best...
ksJoe
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Re: Condensation line in attic / AC air handler

Post by ksJoe »

The suggestion of Pex is good, but the Pex I'm familiar with is not very rigid. To keep a bit of a slope in it, you may need to staple it to a board, or something.

Do you use the AC for dehumidifying in the winter at all? If not, you could just blow it out each fall.

I also wonder about bumping up the size of the pipe. I assume its 1/2 or 3/4? If you replaced it with 1.5" it would be much more rigid (so less low spots). Being that large and rigid, it shouldn't fill with water anywhere. On a horizontal run with it less than 1/4 full it shouldn't break when it freezes.
Normchad
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Re: Condensation line in attic / AC air handler

Post by Normchad »

My AC units are fitted with thee now: https://www.amazon.com/Rectorseal-83626 ... SNFY3AMHZZ

They are transparent p-traps for the drain line, with an easy clean out and attached brush. What’s even better, they also cause the AC to shut off if the line gets plugged. So, if the AC isn’t working, you can quickly check for a stoppage, and if there is one, flip the cap off, rush it out, and you’re on your way again.

This will prevent the overflowed drain pans in most cases I believe.
tigerdoc93
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Re: Condensation line in attic / AC air handler

Post by tigerdoc93 »

The bleach works well to keep lines free of mold. Just remember bleach is bleach and the bricks around the drain will definitely fade.
buhlaxtus
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Re: Condensation line in attic / AC air handler

Post by buhlaxtus »

Pan tablets are made for this and work great in condensate pans or pumps. They are quaternary ammonium compounds so they don't bleach things, and they last longer. No need to reinvent the wheel.

... for the op, please install two proper drain lines, or one drain line in the low hole and a water activated switch in the high hole or in the pan under the unit. Fix or navigate the "various obstructions" so your main drain line can be properly pitched. Do not rely on the emergency backup pan or pump for primary drainage - those will freeze, too.
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mancich
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Re: Condensation line in attic / AC air handler

Post by mancich »

Thanks all, some good suggestions. I am leaning toward using the condensate pump, putting it in a pan next to the handler as I mentioned, then taking the clear tube off in the Fall when I shut off the A/C. The water sensor would be placed in the bottom of the pan that the pump is in, and emits a very loud beeping when it detects water... so if the pump fails and water start to overflow into the pan, the alarm goes off (it also sends me an e-mail). The air handler itself is also already in a pan and has a kill switch that shuts itself off if water starts collecting in that pan.

I have my heating/cooling company coming this week to do my annual check-up on the A/C system, and called them and told them they will also be repairing this situation. Option 1 will be to see if we can raise up the air handler a lot more so I can get a definitive pitch, and then just replace the PVC. Option 2 will be the pump as described above.

Thanks again, I knew I'd get some good feedback from this forum. :beer
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Sandtrap
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Re: Condensation line in attic / AC air handler

Post by Sandtrap »

Normchad wrote: Fri May 29, 2020 7:56 pm My AC units are fitted with thee now: https://www.amazon.com/Rectorseal-83626 ... SNFY3AMHZZ

They are transparent p-traps for the drain line, with an easy clean out and attached brush. What’s even better, they also cause the AC to shut off if the line gets plugged. So, if the AC isn’t working, you can quickly check for a stoppage, and if there is one, flip the cap off, rush it out, and you’re on your way again.

This will prevent the overflowed drain pans in most cases I believe.
+1
Also installed these gizmos.
Works great.
Easy to clean.
j :happy
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Sandtrap
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Re: Condensation line in attic / AC air handler

Post by Sandtrap »

mancich wrote: Fri May 29, 2020 1:29 pm Hello all,

We have two zone A/C with an attic air handler. The condensation PVC pipe coming off it is impossible to pitch properly because of various obstructions, and we have had a couple of incidents over the last 18 years where water remains in the line in the Fall, freezes, causes a crack, then leaks when the A/C is turned on the following late Spring. I am thinking of getting a condensate pump and running a clear tube from the pump to the existing hole where the pvc exits the house. I would put the pump in a large pan, next to the air handler with a water sensor for redundancy. Any POV on if this is a good solution? We have a Little Giant pump for the basement air handler and so far it has worked well.

Thanks.
I have had a number of these situations and was able to get creative with the drain system to enable proper drainage.

Can you post pictures or diagrams?
Maybe there is a solution that creative minds here can gnaw on. . . .

j :happy
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Tubes
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Re: Condensation line in attic / AC air handler

Post by Tubes »

Normchad wrote: Fri May 29, 2020 7:56 pm My AC units are fitted with thee now: https://www.amazon.com/Rectorseal-83626 ... SNFY3AMHZZ

They are transparent p-traps for the drain line, with an easy clean out and attached brush. What’s even better, they also cause the AC to shut off if the line gets plugged. So, if the AC isn’t working, you can quickly check for a stoppage, and if there is one, flip the cap off, rush it out, and you’re on your way again.

This will prevent the overflowed drain pans in most cases I believe.
I'm assuming the freezing is only in the trap, in which case this device is a good solution.

Another idea is the "waterless trap". Not sure if this is code approved most areas though. http://www.deschampstechnologies.com/pr ... -trap.html

Keep it simple. Avoid pumps and gizmos when possible.

My problem is the opposite. In summer, the cold condensate in the trap causes sweating from the humidity in the air (southeast USA). So I actually get dripping from the sweat. I solved it by putting an evaporation pan under the trap, which is enough to handle the sweat drips.
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