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    condensate drain ? (19 Posts)

  • hot rod hot rod @ 2:49 PM
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    condensate drain ?

    This pan lies with about 1/2" of water. The drain connection is about 1/2" from the bottom so the water never drains completely.

    Twice now the drain line has plugged with the rust sludge, which trips the high level switch.

    It doesn't seem like a very good design, and the A coil bracket is rusting away.
  • icesailor icesailor @ 4:20 PM
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    Fine Design:

    What does that do to the ability of the coil to remove moisture from the conditioned air?

    Have you ever seen anything like that before with that manufacturer? Did someone perhaps not read the installation instructions for draining the pan?
    Dis it need an evaporative heater to get rid of that like walk in coolers?
  • don don @ 5:44 PM
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    Media filter

    A good media filter at the equipment would solve the clogged drain and pan issue. That half inch of water is a given with most case coils and air-handler.
    As for humidity the air coming off the coil is close to being 100 % saturated its not to it move out into the room in mixes with room air when the humidity drops. So that little bit of water in that pan does not hurt that much. I can only think of two manufacturers that have the drain line tap in the bottom of the pan.
  • Spence Spence @ 8:54 PM
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    Drain Pan

    Fortunately, we have learned to get away from pan materials that not only do not rust, but also contain antimicrobial agents to keep the nasties out of the drain line, and out of your lungs. You can clean and line the pan, yet by the time you're finished, you have a huge investment that could have gone toward a new system.
  • hot rod hot rod @ 10:13 PM
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    thanks all

    this system was installed two years ago.

    The pan is plastic. I question why the metal case around the A coil sits in the water. If it were elevated I would not have the rust and corrosion.

    It plugged the drain the first year, I contacted the installer, rep and manufacturer. I will try the rep and manufacturer again, this doesn't look like a long lasting product, not to mention the potential mold issue.
  • Techman Techman @ 2:11 AM
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    drain pan

    Does this system have a P trap in the condensate line?
  • Spence Spence @ 6:19 AM
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    If the blower is upstream from the coil you should have an air relief. If the blower is downstream there should be a trap. The 3/4" minimum condensate line should have a 1/4"/ft. drop toward the drain.

    You're holding water. It's not the equipment design, unless the factory missed something we can't see. Something in the installation; coil position perhaps. You're also making lots of water, so I would calculate your air flow to make sure you don't have restrictions that make more water than the drain can handle. The photo makes your could look 20 years old, so the issue was most likely there from the first day.
  • Techman Techman @ 8:50 AM
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    Drain water

    That's a lot of build up in the drain pan. And a lot of stuff to backup ,causing a trip. Where is it coming from? How much stuff is in the actual condensate drain line leaving the unit? Can you check the level of the evap coil/drain pan? How are the evap coils themselves? The air filters? On P traps , I think having a trap both ways is better. When air is blowing out , the water is pushed away from the drain pan hole ,building up in the rest of the pan, the other way air is getting sucked in causing a water backup, pulling water away from the drain hole.The return air airflow also helps to keep the water in the pan. A dirty filter adds to the problem, sucking more air thru the hole.
    This post was edited by an admin on August 21, 2014 8:52 AM.
  • hot rod hot rod @ 12:33 PM
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    floor drain

    directly below the unit. i had the sheetmetal guy make a heavy gauge pan the size of the closet floor, I sealed the pan to the floor drain, like a shower pan. Glad I did there is hardwood floor around this closet. The old system leaked and destroyed the flooring.

    The 3/4 condensate line drops straight down and over 2 feet to the drain, plenty of slope as I had them install the AH up on plastic feet.

    The tech removed the condensate trap yesterday, as that is where it plugs. He put in a tee and a stand piece where the trap was.

    Plenty of humidity here in Missouri, so much water.

    I'm fine with the water in the pan, just concerned with the galv steel A coil frame rusting away sitting in that 1/2' of water.
  • icesailor icesailor @ 3:26 PM
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    Additionally, if the end of the condensate drain goes in to a floor drain or any type of receptor where there is standing water in it, and the condensate drain is inserted into the water seal, it will act like it is double trapped. It needs a air break or air gap to drain properly. I've seen where someone put a piece of rubber drain hose into a icemaker drain pump and the hose was inserted too far in and was in water. They overflowed. You need the free flow of air.
    Don't futz with Mother Nature. She has big teeth to bite you with.
  • Techman Techman @ 1:39 PM
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    The trap was down by the floor ? I'm not sure about that. The I&O manual should show a diagram of the recommended trap setup. All traps collect debris and should be cleaned/flushed out once a year. I make my own trap w/ a 3/4 pipe plug for the cleanout. With a piece of plexi-glass you can see the water backup while the system is running. What do the evap coils look like?
    This post was edited by an admin on August 21, 2014 1:42 PM.
  • icesailor icesailor @ 3:20 PM
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    Vented Drains:

    There's a problem with that drain. I don't have the I/O manual but from a plumbing standpoint, it could be better.
    There is a tee on the bottom horizontal drain with a cap on it. The cap needs to be off to let air in.
    In plumbing, we consider that an indirect waste and it needs a free flow of air from the upper part where it comes through the cabinet and drain pan until it goes in to the trap. Which must be below because I don't see it. If there is some sort of trap arrangement inside the cabinet, and another that is below and I can't see, then it is double trapped and will never drain properly. With ice machines, you need a vertical rising vent that is at least one pipe size larger than the size of the drain through the cabinet to vent the line.
    My old AC Air Handler had a tee with a short open riser on the vertical at the top. The new one has the same set up but it is plugged with a safety switch to stop the unit if the drain plugs and backs up. The problem is that there is at least 30' of I" PVC under the slab and who knows how well it pitches. But that doesn't matter because instead of turning the outside ell down, it is turned up with two more ells to get the drain higher from ground level. Which makes the whole 30+ feet part of a trap. They constantly plug up. You can suck 2+ gallons of water out of the drain. That would be normal. I would say that it is either double trapped or not pitched enough. You need to find a way to blow air through the waste line and give it venting. Its not my trade but I've never seen a full pan like that that didn't have a drain issue. And it had nothing to do with the pan. Usually, they only have enough water in the pan to come up to the bottom of the drain hole. If it gets higher, the drain is plugged. Take that cap off on the bottom. See if it is full of water. There shouldn't be any water in any of those drains.
  • hot rod hot rod @ 5:05 PM
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    the only trap

    is below the concrete slab, a basic floor drain. The horizontal 3/4 PVC condensate line stops at that floor drain, it is not into the water seal at all.

    There was a 3/4 PVC running trap where you see that tee and stand pipe. The tech said it did not need to have two traps.

    It is an upflow so that coil is in positive pressure.

    If the manufacturer states it is alright for the coil case to rust away, I'm tempted to build another drain into that pan that allows all the water out, not allowing 1/2" of standing water.

    It just seems like that coil should be elevated above the standing water, or have a plastic bracketing that would not rust away?

    I have two other AC coils and neither of them are rusting like this.
  • icesailor icesailor @ 12:15 AM
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    standing water:

    That's why I think you have another issue. I've never seen a pan with that amount of water in it. If you haven't seen any other HX'ers of that brand full of water, then I doubt it is the problem. Where the drain runs under the unit, are you sure that it is pitching properly where you can't see it? If the water level in the pan ia completely covering the outlet drain hole, and it isn't pouring out of the end of the drain, something is obstructing it. Whatever is in there, you're going to be surprised when you get it out and what it is. I'll bet there's some interesting science projects inside that drain.
    Those manufactured PVC running traps can be a problem.
    Blow the line out from the pan with air. See what comes out. It should drain easily. If it doesn't, there's a problem.
    Does the coil just sit on the plastic waste pan? I can't imagine putting bolts through the pan to hold it worm. It might leak. Maybe it isn't seated on rails. If you have another one like it in your customer base, go look at it.
    This post was edited by an admin on August 22, 2014 12:22 AM.
  • don don @ 6:17 AM
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    That is dirt running down the coil and in to the pan.It also look like alittle rust along with it.The filter set up is letting alot of bypass air around the filter.i would take a look at the blower wheel and see how dirty it is.that will give you a hint as to what kind of air that is going thru that coil.speaking of air i know you are aware of burning candles,the chemical that people spray in the air to make the house smell good. All add to the demise of a copper with steel end sheets coil.i find that aluminum coils seen to hold up alot better with peoples poor iaq.
  • hot rod hot rod @ 9:19 AM
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    good points

    It's at my mother in laws, age 84, very clean household, no pets, all hardwood and tile flooring :) I do replace the filter twice a year 1" pleated type. I'll look for leaks and check the blower wheel condition , thanks.

    I don't mess with air side stuff much, so I don't have a reference, my other two run clean pans is all I know.
  • icesailor icesailor @ 10:22 AM
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    Return Duct leakage:

    There can also be an issue of duct leakage on the return (negative pressure) in unconfined spaces. Like attics or damp crawl spaces. The one piece of return I see doesn't have any tape seal on it. You can also have a serious infiltration problem into unconditioned spaces which has a high heat and humidity ratio. Like Florida attics with attic ventilation.
    That's an impressive amount of water. The only time I have ever seen pans like that were from long pan drains that had pitch issues. Once because an insulator knocked pitch blocks down and the drain had a sag. It doesn't appear that this is your case.
    I plumbed a house for a well known person. They had two AC systems. One for the second floor and one for the first. They had a very large open stairway to the first floor. The second floor had massive cathedral ceilings. The second floor was VERY hot, no matter what. The first floor was around 60 degrees even though the thermostat was set at 75 or below. The cold air from the second floor was coming down the stairway. They had French doors across the entire Southwest side of the house. The prevailing winds in the Summer are from the Southwest. Hot and humid. Because it was cooler outside than it was on the second floor, they opened all the French doors to the outside to keep the second floor cooler. You needed a sweater to stay downstairs. I noticed that the second floor drains were draining constantly and had puddles on the ground. The first floor AH's didn't run at all.

    The Cooler man said it was normal and always done that way.
  • Spence Spence @ 10:33 AM
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    Drain Line

    I wonder why they did not install the secondary.
  • don don @ 12:56 PM
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    More then likely he has unbalance airflow across that coil. it is possible an air baffle on the coil may have needed to be added or removed depending on application. Never seen a one piece air-handler with the coil upstream of the blower. So I am assuming that is a modular air-handler in the picture.
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