Air Conditioner Drain Line [How to, Issues & Solutions]

An air conditioner drain line is a vital part of the smooth operation of the unit. If there are issues with the drain, it is crucial to find out why and fix it.

Air Conditioner Drain Line Outside House Dripping – What to Do

If you find water dripping outside the house from the drain line of the air conditioner, it may not be a reason to worry. Some air conditioners are designed with drain pipes that channel water directly out of the house. Whenever you use the unit, the condensate will flow out. Hot weather can drip, but not too much.

However, you should worry if the unit has a drain pan and the water leaks out from the drainpipe outside. Also, if the puddle is big, it means something is causing excessive dripping. Check your air filters. When they are significantly dirty, wash or replace them. Otherwise, they will cause the evaporator coil to accumulate ice and freeze. Consequently, there will be excess water from the melting ice.

Next, check the drain line as it may be damaged. If it is broken, that will explain the dripping. You may experience this problem if your air conditioning unit is old. Check the line or hire a professional to do the job. 

While checking the drain line, you may want to check the drain pan. A broken drain pan, which can happen if the air conditioner is old, can cause dripping which you may see outside the house. Contact a professional HVAC technician to check it and recommend a permanent solution.

Other Causes

If the air conditioner is new, it may have been incorrectly installed. One sign of this issue is poor cooling from the air conditioner. So, consider contacting the installers or the manufacturer to check the installation and remedy it if necessary.

Consider resealing the air conditioning unit if you suspect the seal is compromised. Sometimes, poor fittings or loose seals can allow warm air to enter the unit and build condensation. As a result, there is a lot of water, which will leak from any opening, including the line.

Low refrigerant levels can also cause a leak from the drain pipe and other places. If the air conditioner is not cooling properly or has stopped cooling with the dripping water, it may be a sign that the refrigerant is low. And when it is low, the pressure drops and leads to a frozen evaporator coil. When the ice melts, the unit begins to leak.

It is always best to use the services of a professional to check the air conditioning unit. They are trained to find faults and detect possible errors. Then, they can recommend a permanent solution.

How to Clear a Clogged Air Conditioner Drain Line

Use a wet/dry vacuum to clear a clogged drain line in your air conditioner or use vinegar. There is another option of using peroxide if you do not have vinegar or you do not like the smell. This article discusses the detail of cleaning the drain line but you can also opt to employ the services of a professional.

Air Conditioner Drain Line Clogged in Car – Quick Fix

Here is a simple way to clean a clogged drain line in your car without using a drain cleaner:

Get your car and park it on an even surface. Use the emergency brake but ensure you park where there is good lighting so that you can see what you are doing. Find a metal wire and cut about a foot of it. Shape one end into a hook to help you clear the drain.

Find the drain line for the air conditioner under the engine; it is usually a small plastic hose. Pull it away from the engine so that you can inspect it to find the clog. Put the metal wire into the hose but do it carefully so that the metal does not damage the plastic material. Pull and push the wire until you dislodge the clog.

Next, pour water into the drain to ensure it is completely free of the clog. Make sure the water runs free before replacing the line under the engine. Start the car and run the air conditioner to check the drain’s functionality. If there is still a problem, take the car to a technician for servicing.

How to Plumb an Air Conditioner Drain Line

Do the following to plumb or install the drain line in your air conditioner:

Turn the air conditioner off and take some measurements. Measure the length from the drain area to the pan. The condensate must not drain out onto a hardwood floor or cemented floor. It must be on the grass or dirt floor.

Next, drill holes you may need into walls where the lines will fit. If your house is made of bricks, you can create holes by drilling tiny a few holes where the drain exit will be then finish up by hammering the rest with a chisel. But if your house is wood, a drill and a jigsaw will do the job.

Now, measure the size of the space where the drain tube will connect to the pan. That way, you will know the pipe size to purchase. In most cases, you will need a half-inch pipe. You can now measure the length of the pipes to run from the two connections to the drainage points outside your house. Fit the pieces together without using solder or glue so that you can correctly route them. After extending the pipes three feet, drop them at leach an inch for proper connection.

Next, go to the drain pan and fix the two inlet flanges. Using a pipe thread compound, seal their threads before screwing them together, one flange inside the pan and the other outside. Then, fix the pipe and secure it in place with glue or solder. Do it until the pipes get to the outlet holes. Finally, reconnect the air conditioner to electric power.

These steps are quite technical and may not be suitable for an untrained HVAC technician. It is ideal to employ the services of one to plumb or install an air conditioner drain line.

Here is a video showing what it may take to install the drain line in your air conditioner…

Check out these other articles…

How to Clean an Air Conditioner Drain [Detailed Guide]

How to Reset an LG Air Conditioner [Quick Guide]

How to Open an LG Air Conditioner [Detailed Guide]

How to Install an LG Air Conditioner [Detailed Guide]

How to Clean an LG Air Conditioner [Detailed Guide]

How to Set Up an LG Air Conditioner [Quick Guide]

How to Connect an LG Air Conditioner [Plus Issues & Solutions]

Air Conditioner Drain Line Frozen – What to Do

Get some warm water and pour it over the drain line to thaw it. You can also opt to use heat wraps, those types used in hospitals, or a hot water bottle to melt the ice in the drain line. Give it some time to work and ensure you disconnect electric power to the air conditioner while at it.

Consider making the drain line shorter than normal if that will not affect the air conditioner and drainage process. If the condensate has little space, it may not have enough of it to freeze. It may help reduce the chances of freezing in the line. Also, weather-proof sleeves work to prevent freezing if shortening the line is not an option. Simply place it around the drain to work.

You may want to hire a professional to check the drain line and determine whether or not it is frozen and what is causing it. Then, they can thaw it and recommend further fixes to prevent future occurrences.

Air Conditioner Drain Line Gurgling – Solved

Gurgling noise from your drain line may be a sign of a malfunctioning drain pump or a blocked drain line. You may need to check whether it is blocked by debris or ice. If it is debris, use a wet/dry vacuum to suck it out and flush it with vinegar or peroxide to clean it completely.

But if it is ice, use a heat source such as warm water or a hot water bottle to melt the ice. Do this carefully so that you do not damage the drain line or other parts of the unit. Then, find out why there is ice in the line and find a permanent solution. Call a technician to check the durian line if none of the solutions works.

Sewer gases may find their way into the air conditioning system and float into your home if the drain line is clogged. That is why it is best to use the services of a professional to fix the clogging and drainage issues.

Typically, the drain line is a channel that releases condensate from the air conditioner. You should not hear the water draining from the unit, but you may hear a little sound if you stand close to the drain line outside the house. However, if the noise is loud enough for you to hear without much effort, something is blocking the line and the water cannot flow out.

How to Prevent AC Drain Line from Clogging

A clogged air conditioner drain line causes several issues in the unit, including irreparable damage. Therefore, it is crucial to clean the drain line and the unit as often as possible. And make it a monthly ritual if the air conditioner is to work optimally. This article is an in-depth explanation of how to prevent an air conditioner drain line from clogging all the time.

How to Unclog an Air Conditioner Drain Line with Bleach

It is pretty easy to unclog a drain line in your air conditioner with bleach. It is the same as cleaning it with vinegar. Open the drain line; there is usually a cover on it. Mix warm water and bleach in equal parts and pour it into the drain pan. The mixture will flow down the line and wash off bacteria and fungi. Do this a couple of times every year for lasting results.

Newer models have instructions not to use bleach and water solutions to clean the drain line. The same applies to water and vinegar solutions. This is because the solutions may degrade or corrode the manufacturing materials. Only boiling water is needed to clean such drain lines.

air conditioner blowing hot air

How to Clean AC Condensation Line with Shop-Vac

Begin by turning the thermostat off. Next, turn off the circuit breaker that controls the air conditioner. Doing this removes electric current from the air conditioner so that you do not get electrical shocks when cleaning the drain line.

Find the drain line’s endpoint, where water flows out of the air conditioner. If there is no visible exit point, then the condensate may be draining from another point inside the house. But if there is a point outside the house, check to see if there is something obstructing it. You can put on gloves and manually remove the obstruction or use a tool such as a pair of pliers.

Now, get a wet/dry vac and remove the filter to avoid ruining it. If you leave it in, it will get wet and may lead to mildew and mold. Fix the hose of the vacuum to the drain end and secure it tightly with a cloth or duct tape. Then, turn the vacuum on for about five seconds to suck the clog out. Run it at five-second intervals until you have run the vacuum for a minute.

If the clog remains, it may be a job for an HVAC professional. You will know the clog is gone if you pour water into the drain and it runs free and clear. If it does not drain, you know the clog remains.

What Causes an Air Conditioner Drain Pipe to Clog?

Dirty air filters are the typical cause of clogged air conditioner drain pipes. When the filter gets dirty, the dirt can get on the evaporator coil. And when water drips off the coil into the drain pan, it will begin to clog the drain pipe. Over time, it will form a complete obstruction.

A leaking condensate pipe is dangerous to your flooring and wall, as well as the air conditioning unit. It is crucial to find a solution as quickly as possible if you suspect you have a leaking condensate pipe.


An air conditioner drain line can cause irreparable damage to the unit if it is leaking or clogged. Pay close attention to the drain pan if you suspect there is a problem. Hire a qualified HVAC technician to check the air conditioner and other working parts when there is an issue.

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