How to Clean Out Your Air Conditioner's Condensate Line

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air conditioner condensate line clog

Your air conditioner does two jobs: It cools down the air and it dehumidifies the air. If you live in a dry climate, you want the AC to dehumidify as little as possible because it uses extra energy and makes you spend more on lip balm and hand lotion. If you live in a humid climate, you really want it to do that second job as well as it can to keep your indoor air dry and comfortable. But where does all that condensate go?

In most homes, it goes outdoors through a pipe, like the one above. Sometimes there's a little pump that pumps it out, but most often it drains by gravity alone. Occasionally that condensate line gets clogged. This happened at my condo last week. (We live in Atlanta, Georgia, a mixed-humid climate.) Gunk in the pipe built up to the point where it was barely draining. We could run the AC for a little while and then we'd have to turn it off again.

This past weekend I tackled the problem. One of the best ways to do so is with good old air pressure. If you can close off all escape routes except the one in the direction of the clog, you can shoot positive pressure into the pipe near where the indoor unit is located. That should blow the clog out the other end. In our case, that wasn't an option because our condensate line is connected to our upstairs neighbor's air conditioner, too.

So I got out my little wet-dry shop vac and set it up to suck the gunk out at the end of the pipe. The photo below shows the setup.

air conditioner condensate line clean wet dry vacuum

I was hoping to avoid a trip to the hardware store, so I used red duct tape to try to make an airtight connection between the shop vac hose and the condensate line. It didn't work.

air conditioner condensate line clean airtight connection

I took the shop vac hose with me to the store and bought some fittings in the plumbing department. I hooked it all up (photo above) and got a nice, airtight connection this time. With the taped connection, I got maybe half a cup of water out of the pipe. With the airtight connection, I got the bucket full of crud you see below.

air conditioner condensate line sludge

If you really want to see how bad it was, watch the short video below and you can see my wife pouring it out.

Yes, all that gunk was in our condensate line. One problem with condensate lines is that algae can grow in them. In our case, there's also a lot of sediment in that bucket, possibly from a corroded evaporator coil. We replaced our AC in 2009 and the condensate line hasn't been cleaned since then, so some of that crud could have been from our old unit.

If you haven't thought about your condensate line lately (or ever), this would be a good time to do so. You can have your HVAC company make sure it's clean, or you can get a shop vac and do it yourself. To keep it clear, you can use an algaecide that's safe for air conditioners. Your HVAC company can recommend one for you. In hot-humid climates like Florida especially, clogged condensate lines are a frequent problem.

A little preventive maintenance now could save you thousands of dollars in water damage repairs and the loss of your air conditioner when the heat really cranks up.

 

Related Articles

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Comments

Bob Lemley

Try a couple of unions and check the trap you have against the description in the install manual, (they did leave that with you didn't they? it's yours), see if it the proper size and depth. Put service unions on both sides. That way that problem child can easily be removed and cleaned, When maintenance is done have them use an Algaecide CARTRIDGE, nt tablets in your drain pan. Get one for your neighbor too if your going to be tied to the same drain. The slowly feed throughout the season rather than tablets that are gone in a couple days.&nbsp; <br />Vacuuming out is the better way, in my opinion, to clear condensate drains. Then you can get a better look at what is clogging the drain. &nbsp; <br />"Bellies" in condensate drains are a big problem with horizontal runs.

Ray Austin

Allison I think you live in California? I am surprised to see this type of condensate set up there. While I do see some of these type of condensate set ups here in Katy, Texas area it's only in very old sections because codes were passed to not run condensate to the out doors probably due to all the bacteria that typically forms in that water. &nbsp; <br />&nbsp; <br />Building Code: key words for it's going to cost you more. But it's more than that, because codes are there to keep things nice and neat too. Do you really want nasty bacteria laden water spewing out the side of your house? Every time you mow the yard you deposit some of that lovely stuff on the bottom of your shoe. &nbsp; <br />&nbsp; <br />Needless to say if you live in a newer home you likely wouldn't find a condensate set up like this and if you notice ANY dripping from a tube over head from the eave of your house it is a signal you have a condensate problem that could lead to a ceiling cave in, water damage, mold growth, HVAC system damages such as shorting out of motors, circuit boards etc. &nbsp; <br />&nbsp; <br />Many times these drains are quite complex because over the years in my area they have made various changes to how they run these AC condensate lines. While the home owner can use bleach to "TREAT" the drain, you must know where to pour it otherwise you risk damage to your system. Bleach is very corrosive and will damage your system if not used properly and in the proper place. &nbsp; <br />&nbsp; <br />If the drain line is clogged do not pour anything into it, because you will likely only add charges to the job when you find out what you are trying to do doesn't work and decide to seek the help of a professional. &nbsp; <br />&nbsp; <br />Today, if you run AC condensate to the out doors in Katy, Texas area the proper way is to drain this as waste water. You should not drain this water just anywhere. Your health, your pets health and your families health depends on it. &nbsp; <br />&nbsp; <br />Air Conditioning isn't about how much you spend... it's about how much you waste. &nbsp; <br />&nbsp; <br />Unnecessary medical bills, equipment damages, mold growth, pet bills, water damage to your home. (Hire a LICENSED pro.)&nbsp; <br />&nbsp; <br />Proper AC condensate drainage is serious business, much more serious than you might think. &nbsp; <br />

M.Johnson

My AC technician told me we should pour a cup or so of Clorox into a fitting in the condensate line, up near the coil. Does your equipment have any such fitting, and what do you think of it?

Richard Parker

Hopefully that was not your emergency overfill line rather than the normal condensate line. Coils have two, sometimes the second is not plumbed but it should be. Often the primary line is connected to the house's drain with the secondary exposed like your's or both pipes are run outside directly.

Bill Hill

That's my kind of problem solving! Thanks, Allison, for the post with the, as always, clear description and photos.

Curt Kinder

NO Bleach!&nbsp; <br />&nbsp; <br />Consider that pool water heat exchangers designed to deal with just a few parts per million chlorine, are generally made of titanium, and bleach has 82500 ppm Chlorine, and air handlers aren't made of Titanium, just the fumes from bleach pose a risk.&nbsp; <br />&nbsp; <br />Many HVAC system replacements arise from unrepairable air handler coil refrigerant leaks.

Tom Frymire

I agree with commentator Roy Austin on several points. Especially his caution on the use of bleach - it is a VOC and should not be poured into the condensate. Not only is it an irritant and a health hazard but it can also corrode the fins on evaporator coils. The HVAC manufacturers do not recommend the use of bleach and other caustic chemicals due to fears of formicary corrosion.

Bob Lemley

Try a couple of unions and check the trap you have against the description in the install manual, (they did leave that with you didn't they? it's yours), see if it the proper size and depth. Put service unions on both sides. That way that problem child can easily be removed and cleaned, When maintenance is done have them use an Algaecide CARTRIDGE, nt tablets in your drain pan. Get one for your neighbor too if your going to be tied to the same drain. The slowly feed throughout the season rather than tablets that are gone in a couple days. 
Vacuuming out is the better way, in my opinion, to clear condensate drains. Then you can get a better look at what is clogging the drain.  
"Bellies" in condensate drains are a big problem with horizontal runs.

Ray Austin

Allison I think you live in California? I am surprised to see this type of condensate set up there. While I do see some of these type of condensate set ups here in Katy, Texas area it's only in very old sections because codes were passed to not run condensate to the out doors probably due to all the bacteria that typically forms in that water.  
 
Building Code: key words for it's going to cost you more. But it's more than that, because codes are there to keep things nice and neat too. Do you really want nasty bacteria laden water spewing out the side of your house? Every time you mow the yard you deposit some of that lovely stuff on the bottom of your shoe.  
 
Needless to say if you live in a newer home you likely wouldn't find a condensate set up like this and if you notice ANY dripping from a tube over head from the eave of your house it is a signal you have a condensate problem that could lead to a ceiling cave in, water damage, mold growth, HVAC system damages such as shorting out of motors, circuit boards etc.  
 
Many times these drains are quite complex because over the years in my area they have made various changes to how they run these AC condensate lines. While the home owner can use bleach to "TREAT" the drain, you must know where to pour it otherwise you risk damage to your system. Bleach is very corrosive and will damage your system if not used properly and in the proper place.  
 
If the drain line is clogged do not pour anything into it, because you will likely only add charges to the job when you find out what you are trying to do doesn't work and decide to seek the help of a professional.  
 
Today, if you run AC condensate to the out doors in Katy, Texas area the proper way is to drain this as waste water. You should not drain this water just anywhere. Your health, your pets health and your families health depends on it.  
 
Air Conditioning isn't about how much you spend... it's about how much you waste.  
 
Unnecessary medical bills, equipment damages, mold growth, pet bills, water damage to your home. (Hire a LICENSED pro.) 
 
Proper AC condensate drainage is serious business, much more serious than you might think.  

Allison Bailes

<b>Bob L.</b>: Good advice about the cartridge rather than the tablet. Thanks!&nbsp; <br />&nbsp; <br /><b>Ray A.</b>: No, I live in Georgia, not California. We're definitely humid here. And no, I definitely don't live in a new house either. It's a 45 year old condo. Regarding proper drainage, that wasn't the purpose of this article, but since you brought it up, the IRC says this: "Condensate shall not discharge into a street, alley or other areas where it would cause a nuisance." In Georgia, I see plenty of new homes with condensate lines draining onto the ground in the back or on the side of the house. Maybe building inspectors in Katy, Texas are more strict in their interpretation of that statement than they are here in Georgia. I'm not saying that's the best way to do it, but I've never heard of any people or pets getting sick from condensate either.&nbsp; <br />&nbsp; <br /><b>M. Johnson</b>: I've removed my recommendation for pouring bleach into the condensate line because the contractors have spoken up loud and clear on that issue. Algaecides made for air conditioners are the way to go.&nbsp; <br />&nbsp; <br /><b>Richard P.</b>: Nope. That was the primary drain line. The secondary, as you mentioned, is not connected in our home. &nbsp; <br />&nbsp; <br /><b>Bill H.</b>: You're welcome. Please note my change on the bleach issue.&nbsp; <br />&nbsp; <br /><b>Curt K.</b>: Got it. Article revised. When I've done it, I always dilute it and flush it with lots of water, but you're right. Do you have a recommendation for algaecide? And what about the issue of cartridge vs. tablet that Bob Lemley raised?&nbsp; <br />&nbsp; <br /><b>Rom F.</b>: I've revised the article to remove the bleach recommendation. &nbsp; <br />&nbsp; <br />

M.Johnson

My AC technician told me we should pour a cup or so of Clorox into a fitting in the condensate line, up near the coil. Does your equipment have any such fitting, and what do you think of it?

Richard Parker

Hopefully that was not your emergency overfill line rather than the normal condensate line. Coils have two, sometimes the second is not plumbed but it should be. Often the primary line is connected to the house's drain with the secondary exposed like your's or both pipes are run outside directly.

Roy

I am glad that you amended the bleach recommendation. It is not compatible with aluminum fins. I have heard others recommend vinegar, and that is even worse because it can cause formicary corrosion in copper coils.

Regan Murphy

I think putting a shop vac on the drain outlet is the safest way to clear a drain if you have access to the termination point. Negative pressure is much safer than positive pressure especially if you don't know how well all of the PVC connections are put together. In some homes and situations this will not work if you have multiple air handlers tied into one primary drain. If the clog occurs between one of the air handlers and where the drains tee together, then vacuuming from the termination will just pull air from the drain that isn't clogged. In this case you will need to cut the drains between each air handler and the tee and blow them out or vacuum them out from that point. Alternatively you can install PVC ball valves near each air handler so that you can isolate each drain before vacuuming the termination point. 2015 IMC and IRC codes say that you need to be able to clear blockages and perform maintenance on drains without having to cut the pipe.&nbsp; <br /> &nbsp; <br /> <a href="http://allaccessdevice.com/home.html">Here's a device that can make maintenance easier</a>

Bill Hill

That's my kind of problem solving! Thanks, Allison, for the post with the, as always, clear description and photos.

Curt Kinder

NO Bleach! 
 
Consider that pool water heat exchangers designed to deal with just a few parts per million chlorine, are generally made of titanium, and bleach has 82500 ppm Chlorine, and air handlers aren't made of Titanium, just the fumes from bleach pose a risk. 
 
Many HVAC system replacements arise from unrepairable air handler coil refrigerant leaks.

Tom Frymire

I agree with commentator Roy Austin on several points. Especially his caution on the use of bleach - it is a VOC and should not be poured into the condensate. Not only is it an irritant and a health hazard but it can also corrode the fins on evaporator coils. The HVAC manufacturers do not recommend the use of bleach and other caustic chemicals due to fears of formicary corrosion.

Allison Bailes

Bob L.: Good advice about the cartridge rather than the tablet. Thanks! 
 
Ray A.: No, I live in Georgia, not California. We're definitely humid here. And no, I definitely don't live in a new house either. It's a 45 year old condo. Regarding proper drainage, that wasn't the purpose of this article, but since you brought it up, the IRC says this: "Condensate shall not discharge into a street, alley or other areas where it would cause a nuisance." In Georgia, I see plenty of new homes with condensate lines draining onto the ground in the back or on the side of the house. Maybe building inspectors in Katy, Texas are more strict in their interpretation of that statement than they are here in Georgia. I'm not saying that's the best way to do it, but I've never heard of any people or pets getting sick from condensate either. 
 
M. Johnson: I've removed my recommendation for pouring bleach into the condensate line because the contractors have spoken up loud and clear on that issue. Algaecides made for air conditioners are the way to go. 
 
Richard P.: Nope. That was the primary drain line. The secondary, as you mentioned, is not connected in our home.  
 
Bill H.: You're welcome. Please note my change on the bleach issue. 
 
Curt K.: Got it. Article revised. When I've done it, I always dilute it and flush it with lots of water, but you're right. Do you have a recommendation for algaecide? And what about the issue of cartridge vs. tablet that Bob Lemley raised? 
 
Rom F.: I've revised the article to remove the bleach recommendation.  
 

Lori

Crimeny. I read the ENTIRE comment thread hoping SOMEBODY would finally answer your question of what algaecide tablet to buy and no such luck. Lots of stuff about Legionnaire's disease, though. (good grief).

We rent a condo, are on the 3rd floor,and have a sputtery window A/C unit leading us to want to treat that standing water in the condensate pan.

Can anybody recommend a specific product/ place to purchase?

Thanks!

(the hand licking comment post-bathroom trip cracked me up good!!)

Jeremy

Shouldn't the hole the condensate line comes out of in the house be air sealed, both for air and for bugs? Maybe it is and that's just not clear in the picture or video...

Steve Wacl.

Allison,&nbsp; <br />&nbsp; <br />An excellent suggestion for one of those "out of sight..." issues that seldom gets attention till it presents as an unwanted wet spot... In addition, you mention your condo is 45 years old and I would posit that line has not been flushed since, umm, 1970 (!).&nbsp; <br />&nbsp; <br />At the risk of being a smart a$&amp; (which has never stopped me before :), I believe the source of your problem with establishing a good seal on the condensate discharge was the use of red duct tape. As everyone knows (except you, apparently :), considerable scientific evidence exists demonstrating that <red> tape is vastly inferior to the traditional grey flavor. I'll forward a link...when I discover one.&nbsp; <br />&nbsp; <br />All the best.</red>

Roy

Here are a couple of more condensate drain issues. A well-designed trap is meant to keep air from being sucked into the air handler or blown out of it, depending on the coil location relative to the blower. Preventing air from being sucked in is good for health reasons, especially when you drain to the sanitary sewer. Perhaps the trap also keeps bugs from entering when the drain is plumbed to the outdoors. So what happens in the winter when the furnace or heat pump is operating? Does the trap dry out and quit "working"?&nbsp; <br />&nbsp; <br />What about the overflow drain? Should it be trapped for the same reasons? If so, how can the trap work if water doesn't normally flow through it?

Roy

I am glad that you amended the bleach recommendation. It is not compatible with aluminum fins. I have heard others recommend vinegar, and that is even worse because it can cause formicary corrosion in copper coils.

Regan Murphy

I think putting a shop vac on the drain outlet is the safest way to clear a drain if you have access to the termination point. Negative pressure is much safer than positive pressure especially if you don't know how well all of the PVC connections are put together. In some homes and situations this will not work if you have multiple air handlers tied into one primary drain. If the clog occurs between one of the air handlers and where the drains tee together, then vacuuming from the termination will just pull air from the drain that isn't clogged. In this case you will need to cut the drains between each air handler and the tee and blow them out or vacuum them out from that point. Alternatively you can install PVC ball valves near each air handler so that you can isolate each drain before vacuuming the termination point. 2015 IMC and IRC codes say that you need to be able to clear blockages and perform maintenance on drains without having to cut the pipe. 
 
Here's a device that can make maintenance easier

L Burgess

Thank you so much for mentioning this ingenious device -- I just ordered one!

Regan Murphy

Allison, What is the other drain pipe below? It looks like PVC with a wrought iron elbow. Are you sure that it's not your primary drain and you are vacuuming out the auxiliary drain?&nbsp; <br />&nbsp; <br />Roy, Condensate drains shouldn't be drained directly in to a sewer, if they aren't run outside they should tie in above the plumbing trap of a bathroom sink or other trap that would be presumed to stay wet through out the year. &nbsp; <br />&nbsp; <br />Condensate traps are typically more important for heat pump/electric heat systems because in most of those systems the drain is under negative pressure pulling into the air handler. So yes, in the winter time the trap(s) do dry out and pull air in from wherever the drains terminate. Also negative pressure air handlers can have trouble draining condensate without the trap and the water in the trap to break the air, condensate has trouble draining out against the air vacuum and may end up in the duct system. Condensate drain problems are probably the single biggest reason people get mold in fiberglass duct systems.&nbsp; <br />&nbsp; <br />On just about all systems with gas furnaces the drain is under positive pressure so they don't need the trap to drain properly. It's still a good idea to have a condensate trap on these systems to prevent energy loss from air blowing out the drain and also to prevent bugs or odors from coming through the drain in the off cycle.&nbsp; <br />&nbsp; <br />Both the primary and auxiliary drains should be trapped. &nbsp; <br />&nbsp; <br />On positive pressure systems the air pressure will tend to spit water out of the auxiliary drain due to air pressure. So you end up losing energy from lost air and you may prematurely rust out an auxiliary drain pan. &nbsp; <br />&nbsp; <br />On negative pressure systems you want the auxiliary drain to also be trapped because when the primary drain clogs you REALLY need the auxiliary drain to drain effectively or you will end up with water in your ducts.

Jeremy

Shouldn't the hole the condensate line comes out of in the house be air sealed, both for air and for bugs? Maybe it is and that's just not clear in the picture or video...

Steve Wacl.

Allison, 
 
An excellent suggestion for one of those "out of sight..." issues that seldom gets attention till it presents as an unwanted wet spot... In addition, you mention your condo is 45 years old and I would posit that line has not been flushed since, umm, 1970 (!). 
 
At the risk of being a smart a$& (which has never stopped me before :), I believe the source of your problem with establishing a good seal on the condensate discharge was the use of red duct tape. As everyone knows (except you, apparently :), considerable scientific evidence exists demonstrating that tape is vastly inferior to the traditional grey flavor. I'll forward a link...when I discover one. 
 
All the best.

Roy

Here are a couple of more condensate drain issues. A well-designed trap is meant to keep air from being sucked into the air handler or blown out of it, depending on the coil location relative to the blower. Preventing air from being sucked in is good for health reasons, especially when you drain to the sanitary sewer. Perhaps the trap also keeps bugs from entering when the drain is plumbed to the outdoors. So what happens in the winter when the furnace or heat pump is operating? Does the trap dry out and quit "working"? 
 
What about the overflow drain? Should it be trapped for the same reasons? If so, how can the trap work if water doesn't normally flow through it?

Regan Murphy

Allison, What is the other drain pipe below? It looks like PVC with a wrought iron elbow. Are you sure that it's not your primary drain and you are vacuuming out the auxiliary drain? 
 
Roy, Condensate drains shouldn't be drained directly in to a sewer, if they aren't run outside they should tie in above the plumbing trap of a bathroom sink or other trap that would be presumed to stay wet through out the year.  
 
Condensate traps are typically more important for heat pump/electric heat systems because in most of those systems the drain is under negative pressure pulling into the air handler. So yes, in the winter time the trap(s) do dry out and pull air in from wherever the drains terminate. Also negative pressure air handlers can have trouble draining condensate without the trap and the water in the trap to break the air, condensate has trouble draining out against the air vacuum and may end up in the duct system. Condensate drain problems are probably the single biggest reason people get mold in fiberglass duct systems. 
 
On just about all systems with gas furnaces the drain is under positive pressure so they don't need the trap to drain properly. It's still a good idea to have a condensate trap on these systems to prevent energy loss from air blowing out the drain and also to prevent bugs or odors from coming through the drain in the off cycle. 
 
Both the primary and auxiliary drains should be trapped.  
 
On positive pressure systems the air pressure will tend to spit water out of the auxiliary drain due to air pressure. So you end up losing energy from lost air and you may prematurely rust out an auxiliary drain pan.  
 
On negative pressure systems you want the auxiliary drain to also be trapped because when the primary drain clogs you REALLY need the auxiliary drain to drain effectively or you will end up with water in your ducts.

Dan Geist

I called an HVAC company out to my home to diagnose a no-cool situation last year. They came out and tested the outside unit (pressure and short-circuit tests) and it spun up fine, the line-set got cold, etc. The service tech opened up the air handler and quickly stated "Oh, you have a bad thermostat. I can install this whizbang-5000 unit for you for only $300." I asked why I needed all those features for an older system...he didn't have an answer and I politely declined. After a trip to the big orange box for the 19.99 thermostat and installing it, the same problem persisted. So, this time I troubleshot the electrical myself (I'm an engineer, BTW). Turns out the condensate line had completely blocked and the pump had burned itself out from running near 24/7. Overnight delivery from Amazon of a little-giant pump and some new poly tubing solved the problem for about $40 and the store took back my unnecessary new thermostat. I never did recoup the costs of that useless service visit from that HVAC company.&nbsp; <br />

Dan Geist

I called an HVAC company out to my home to diagnose a no-cool situation last year. They came out and tested the outside unit (pressure and short-circuit tests) and it spun up fine, the line-set got cold, etc. The service tech opened up the air handler and quickly stated "Oh, you have a bad thermostat. I can install this whizbang-5000 unit for you for only $300." I asked why I needed all those features for an older system...he didn't have an answer and I politely declined. After a trip to the big orange box for the 19.99 thermostat and installing it, the same problem persisted. So, this time I troubleshot the electrical myself (I'm an engineer, BTW). Turns out the condensate line had completely blocked and the pump had burned itself out from running near 24/7. Overnight delivery from Amazon of a little-giant pump and some new poly tubing solved the problem for about $40 and the store took back my unnecessary new thermostat. I never did recoup the costs of that useless service visit from that HVAC company. 

Ray Austin

Allison, It's called Legionnaire's Disease&nbsp; <br />&nbsp; <br />The bacterium Legionella pneumophila is responsible&nbsp; <br />for most cases of Legionnaires' disease. &nbsp; <br />Outdoors, legionella bacteria survive in soil and &nbsp; <br />water, but rarely cause infections. Indoors, though,&nbsp; <br />legionella bacteria can multiply in&nbsp; <br />all kinds of water systems &mdash; hot tubs, air conditioners &nbsp; <br />and mist sprayers in grocery store produce departments.&nbsp; <br />&nbsp; <br />The code in this area more or less states the same&nbsp; <br />reasoning... "so the water will not cause a nuisance"&nbsp; <br />&nbsp; <br />I'm sure a lawyer wrote that statement. &nbsp; <br />&nbsp; <br />Additionally, the tablets that are used to kill the bacteria&nbsp; <br />if put in separately can swell, float down and &nbsp; <br />clog the drain. &nbsp; <br />&nbsp; <br />The best way to fix the problem is design...&nbsp; <br />&nbsp; <br />Bacteria can't grow without water. Water does not&nbsp; <br />pool if gravity doesn't allow it to do so. &nbsp; <br />&nbsp; <br />

Ray Austin

Allison, It's called Legionnaire's Disease 
 
The bacterium Legionella pneumophila is responsible 
for most cases of Legionnaires' disease.  
Outdoors, legionella bacteria survive in soil and  
water, but rarely cause infections. Indoors, though, 
legionella bacteria can multiply in 
all kinds of water systems — hot tubs, air conditioners  
and mist sprayers in grocery store produce departments. 
 
The code in this area more or less states the same 
reasoning... "so the water will not cause a nuisance" 
 
I'm sure a lawyer wrote that statement.  
 
Additionally, the tablets that are used to kill the bacteria 
if put in separately can swell, float down and  
clog the drain.  
 
The best way to fix the problem is design... 
 
Bacteria can't grow without water. Water does not 
pool if gravity doesn't allow it to do so.  
 

Debbie

I never pictured you &amp; your family in a condo.&nbsp; <br />an energy efficient ongoing building science experiment house...but not a condo!

Debbie

I never pictured you & your family in a condo. 
an energy efficient ongoing building science experiment house...but not a condo!

Ray Austin (Austin Air Co)

Debbie, The internet is the wild west and anyone with a little amount of money can set up shop write a blog and appear like they are a renowned expert. When their true life is much different than anyone would ever think.&nbsp; <br />&nbsp; <br />But you and everyone else, must realize you nor anyone else starts their career at the top to work down, they start at the bottom to work their way up. &nbsp; <br />&nbsp; <br />With that said, this venue should be set with the aspect of learning something... regardless of where someone lives. Focus on the prospect of learning something new that you did not know. &nbsp; <br />&nbsp; <br />The hope is that Allison and his family escapes this science experiment gone bad without getting sick. &nbsp; <br />

Ray Austin (Austin Air Co)

Debbie, The internet is the wild west and anyone with a little amount of money can set up shop write a blog and appear like they are a renowned expert. When their true life is much different than anyone would ever think. 
 
But you and everyone else, must realize you nor anyone else starts their career at the top to work down, they start at the bottom to work their way up.  
 
With that said, this venue should be set with the aspect of learning something... regardless of where someone lives. Focus on the prospect of learning something new that you did not know.  
 
The hope is that Allison and his family escapes this science experiment gone bad without getting sick.  

Allison Bailes

<b>Roy</b>: All good questions regarding condensate lines and traps. But you forgot one: What about those air conditioners that don't have a trap? I've seen plenty. &nbsp; <br /> &nbsp; <br /><b>Regan M.</b>: The other pipe, which is all galvanized steel, is the T&P; relief line for the water heater. I do know the difference between primary and secondary condensate lines. &nbsp; <br /> &nbsp; <br /><b>Jeremy</b>: The hole at the end of the pipe can't be sealed to prevent bugs from entering without also preventing water from exiting. But the trap, if properly designed and installed, should do that. &nbsp; <br /> &nbsp; <br /><b>Steve W.</b>: It's quite possible that this was the first time it was flushed. I used the red tape because that's what we had. &nbsp; <br /> &nbsp; <br /><b>Dan G.</b>: Interesting story. I had to replace the condensate pump at my in-laws' house a few years ago, too, but quickly figured out that was the source of the problem without having to call in their HVAC company. &nbsp; <br /> &nbsp; <br /><b>Debbie</b>: Well, I used to live in the super green house I built in 2001, but then I got a divorce and the economy crashed. &nbsp; <br /> &nbsp; <br /><b>Ray A.</b>: "The hope is that Allison and his family escapes this science experiment gone bad without getting sick." Really? You know enough about my condo to make that pronouncement?

Richard P

Who would have thought condensate drains would stir such emotion? To bad there is not a payback period. If would could that going on a national scale, we would have something.

Debbie

well, well, well...&nbsp; <br />&nbsp; <br />no offense intended Allison.&nbsp; <br />&nbsp; <br />my comment wasn't to insult&nbsp; <br />condo dwellers. at times I wish&nbsp; <br />I lived in a place where problems&nbsp; <br />were solved by picking up a phone&nbsp; <br />rather than a tool.&nbsp; <br />&nbsp; <br />to get back on sort of on topic...&nbsp; <br />I drain my condensate into&nbsp; <br />a flower bed...home to the&nbsp; <br />best watered plants in the yard.&nbsp; <br />no problems with clogged drain&nbsp; <br />as yet.&nbsp; <br />

Ray Austin

Allison, look at what you just removed &nbsp; <br />from your air conditioner. &nbsp; <br />&nbsp; <br />Can you honestly say that this is "Perfectly Fine"? If you can&nbsp; <br />say that with a straight face, I will say no more. I issued my&nbsp; <br />warning, you can choose to ignore it if you wish. &nbsp; <br />&nbsp; <br />All this "stuff" that you removed starts some where.&nbsp; <br />Where do you suppose it started?&nbsp; <br />&nbsp; <br />With 20 years of physically being in homes and &nbsp; <br />seeing these things first hand, I may be the &nbsp; <br />wrong one to ask the question you asked of me (Really? You know enough about my condo to make that pronouncement?)&nbsp; <br />&nbsp; <br />Allison, I tend to stand on the side of caution, because&nbsp; <br />at some point your air conditioner will be &nbsp; <br />shut off and things will begin to dry out.&nbsp; <br />&nbsp; <br />Realize Legionnaires Disease is an air borne virus. &nbsp; <br />&nbsp; <br />My HVAC license terminates with an "E" at the&nbsp; <br />end of it. Guess what that "E" stands for?&nbsp; <br />&nbsp; <br />"Environmental"&nbsp; <br />&nbsp; <br />Don't play a high risk game with your health, it's not worth &nbsp; <br />it on any level. &nbsp; <br />

Dan Geist

<b>Debbie:</b> Funny you should mention plants. My previous home had the condensate from the air handler run to an external (properly installed) drip tube near the front porch. It was a very high efficiency unit and it pulled a LOT of moisture out of the air. The azalea located about 2 feet away was the healthiest I've ever seen and it bloomed for about 6 months every year (acidic, warm water, just like they use at Augusta National :)

Allison Bailes

<b>Richard P.</b>: Yeah, I had no idea AC condensate was such a controversial topic!&nbsp; <br />&nbsp; <br /><b>Debbie</b>: And no offense taken. I've written about both my former house and my condo here plenty of times. I'm finally at the point where we can start really improving the condo now, so you'll read more about that in the future.&nbsp; <br />&nbsp; <br /><b>Ray A.</b>: Yes, the condensate line was clogged and I removed a bucket of nasty stuff from it. Where's your evidence that this has ever caused a health problem, especially Legionnaires' disease, in anyone's home? I'd be a lot more worried about the <a href="http://www.energyvanguard.com/blog-building-science-HERS-BPI/bid/59612/A... possum lying next to the disconnected return duct in the crawl space</a>. (And no, that wasn't a "science experiment" at my condo.)&nbsp; <br />&nbsp; <br />And going back to your first comment, where's your evidence that depositing AC condensate on the ground has ever caused health problems in people or pets? I'm all for erring on the side of caution, but let's not be ridiculous.&nbsp; <br />&nbsp; <br />Perhaps you should learn more about Legionnaires' disease and Legionella pneumophila. Here's what OSHA says about it:&nbsp; <br />&nbsp; <br /><i>"Legionnaires' disease bacteria (LDB) cannot survive without water, and a properly operated, well-maintained HVAC system is unlikely to be a source of problems unless water contaminated with the bacteria enters the system. Air conditioning units without humidifiers have not been identified as sources of LDB. For a Legionnaires' disease outbreak to be linked directly with the HVAC system, LDB-contaminated water must enter the system, be aerosolized, and be delivered to building occupants."</i>&nbsp; <br />&nbsp; <br />Legionella.org says:&nbsp; <br />&nbsp; <br /><i>"We are not aware of any cases of Legionnaires' disease acquired from a condensate pan or drain. There would be little opportunity for significant exposure."</i>&nbsp; <br />&nbsp; <br />Legionella pneumophila can be a problem in large commercial air conditioners found in large buildings like hotels, hospitals, and office buildings, not the air conditioners in people's homes.&nbsp; <br />&nbsp; <br />I know you're a smart guy, Ray, and you know a heck of a lot about HVAC, but you might want to reconsider your tone when you comment here. You're coming off as condescending and pompous.

Allison Bailes

<b>Ray A.</b>: One more thing. You wrote: "I issued my warning, you can choose to ignore it if you wish." The only warning I saw was that I shouldn't drain condensate into the backyard (which also runs, by the way, behind the hedges, onto the downspout diverter, where it gets washed away and diluted with every rainstorm) and that air conditioner condensate can cause Legionnaires' disease. Did you have any recommendations?

Regan Murphy

I like to run the outdoor condensate drains to a dry well or french drain. It helps to disperse the water without it pooling too much. I actually prefer to run them outside as opposed to a plumbing drain. When they run to the sink, the sink will eventually clog and when it does the plumber blames the AC guy and the AC guy blames the plumber. Here in San Antonio, commercial new construction code actually requires all of the condensate to be run to a rainwater collection system.

Cameron Taylor

To Ray Austin:&nbsp; <br />&nbsp; <br /><i>Realize Legionnaires Disease is an air borne virus. &nbsp; <br /> &nbsp; <br />My HVAC license terminates with an "E" at the &nbsp; <br />end of it. Guess what that "E" stands for? &nbsp; <br /> &nbsp; <br />"Environmental"</i><i>&nbsp; <br />&nbsp; <br />It is true Legionnaire's disease can be spread via inhalation. It is also true said virus prefers an environment between 77 and 113&deg;F to thrive. Favorable climates for this would be improperly treated HVAC cooling towers and hot tubs, along with hot water tanks.&nbsp; <br />&nbsp; <br />I have not heard of this disease being transmitted via a/c coil condensate, but that's not to say it's not possible for such to be a source.&nbsp; <br />&nbsp; <br />Regarding Allison and his condo, I know him beyond his blog presence, and can vouch for his sound knowledge and reasoning in building science. Even so, he's still learning all along, as am I, as are all of us interested in this discipline. I think that serves the conversation better than waving our letters, degrees, etc. around like that by default confers final authority.</i>

Allison Bailes

Roy: All good questions regarding condensate lines and traps. But you forgot one: What about those air conditioners that don't have a trap? I've seen plenty.  
 
Regan M.: The other pipe, which is all galvanized steel, is the T&P; relief line for the water heater. I do know the difference between primary and secondary condensate lines.  
 
Jeremy: The hole at the end of the pipe can't be sealed to prevent bugs from entering without also preventing water from exiting. But the trap, if properly designed and installed, should do that.  
 
Steve W.: It's quite possible that this was the first time it was flushed. I used the red tape because that's what we had.  
 
Dan G.: Interesting story. I had to replace the condensate pump at my in-laws' house a few years ago, too, but quickly figured out that was the source of the problem without having to call in their HVAC company.  
 
Debbie: Well, I used to live in the super green house I built in 2001, but then I got a divorce and the economy crashed.  
 
Ray A.: "The hope is that Allison and his family escapes this science experiment gone bad without getting sick." Really? You know enough about my condo to make that pronouncement?

Michael B

We have 2 HVAC Units in our finished basement (where we reside several hours per day) that drain into a sump pit. One is inches away from the pit; the other is approx. 50 feet away. Other than condensate from the HVAC units, this pit never has any other water in it. So the condensate that runs into the pit is never expelled. The, sump pit would seem to be a prefect mold breeding ground. Hence, my search for a way to keep both the (under the floor) 50’ drain pipe and pit as mold free as possible. Is there some sort of product/solution – e.g. bleach, peroxide etc. that could be safely run through the drain pipe and poured into the sump pit to prevent mold growth? Safe as in non-harmful to the sump pump, the PVC drain pipe and human health?