How Much Water Should Be In AC Drip Pan?

An air conditioning unit has a drip pan and condensate drain. Water vapor from warm air that passes through the evaporator coil collects in the drip pan. The excess water then flows to the outside through the drain line. A clogged drain pipe may cause excess water to accumulate in the drip pan. Therefore, knowing the amount of water in the AC drain pan is important.

How much water should be in an AC drip pan?

The water in the AC drip pan should be between 5 to 20 gallons each day on average. However, the exact amount of water depends on the weather conditions. During a completely normal day, the amount may be about 10 gallons. However, during exceptionally hot days, the amount in your ac drain line increases dramatically.

Should there be Water in the AC Drip Pan? 

It is completely normal to have water in the AC drip pan. The water comes from the humidity that is in warm air. As long as your air conditioners are working, water shall be present in the drip pans. The water usually accumulates in the pans before traveling through the condensate drain line.

If you realize that there is no water in the pan, your air conditioning system is not working. Similarly, if you realize the unit is draining water excessively, your air conditioner is not working properly. For example, you may have a clogged drainpipe, a frozen evaporator coil, or a refrigerant leak.

How does an AC Produce Water?

When things are perfectly normal, warm air from the outside passes through the evaporator coils. The evaporator coils contain a refrigerant that cools the air. Heat exchange causes the warm air to lose its humidity and temperature. The lost humidity then condenses into water.

The drain pan collects the water from the evaporator coils. It then channels the water through the condensate drain line. The condensate drain line leads to the outside near the air handler and outdoor unit.

How Much Condensation from AC is Normal?

An air conditioning system should release between 5 and 20 gallons of condensate every day. During very hot summer days of high humidity, your AC system will produce a lot of condensates. This is because a lot of hot air passes over the evaporator coils. As a result, a large amount of water vapor collects in the drip pan.

During cold days, your air conditioning system will not have to cool large volumes of air to keep the indoor temperature low. Thus, the central air conditioners will produce far less condensate during such days.

Causes of Overflow in the AC Drip Pan

A Clogged Drain Line

A clogged condensate drain line causes water to overflow in the drain pan. The condensate line blocks because of the accumulation of debris and mold growth. It is easy to fix a clogged drain line.

You can physically open and clean it with a cup of vinegar. This will dissolve all the solid waste and open up the line.

A Tilted Drain Pan

The drain pan collects condensate drain from the evaporator coils. If the pan is tilted, the water will overflow. The pan should be straight up to collect water normally and pass it to the drain line.

However, tilted drain pans can occur during the installation process. If this is the case, you can get a certified HVAC technician to correct the fault. Inspecting the drain pan will show if this is a problem.

Low Refrigerant Level

Low refrigerant levels may dramatically increase the rates of water dripping from your evaporator coil. This occurs when you have a refrigerant leak deep inside your indoor unit.

A frozen evaporator coil increases the dripping water rate in your AC system. You can have an HVAC technician check and fix this problem for you.

A Broken Condensate Pump

A condensate pump carries the condensate from the pan to the drain line. Excess water will not flow from the air conditioner’s drip pan to the AC drain line if the pump breaks.

This will cause the excess water to overflow inside your air conditioning system. You can call a technician to examine your AC unit and fix a broken condensate pump.

How to Tell if an AC Condensate Drain Line is clogged? 

It is easy to tell if you have a clogged condensate drain line. Here are the clear lines that your drain line is blocked.

Standing Water Lear the Indoor Unit

Your condensate lines are clogged when you have standing water near the indoor unit or air handler. This happens because the water cannot move from the condensate pan to the drain and then outside. You will have to unclog the drain line for the water to move smoothly.

AC System Shuts Down

The drip line is likely clogged when the AC system suddenly shuts down or refuses to get back on. Clogging the line interferes with how the internal components of your unit function. You will need the services of an HVAC technician to troubleshoot.

A Musty Smell

When you have a musty smell near the indoor unit of your air conditioner or from the air vents, the drain line is likely clogged. Clogging may be a result of the accumulation of mold.

The smell of the mold that may be blocking the line then spreads around the vent system. Therefore, the smell may also be pronounced near your indoor unit.

Water Damage

When water accumulates near the indoor unit of your air conditioner because of poor drainage, it may cause damage. Thus, water damage is a clear sign of a clogged AC drain line or drip pans.

Water damage may take the form of corrosion of the metal parts of your unit. If your air conditioning system is working perfectly normal, no water damage occurs near the indoor unit.

How to Unclog AC Condensate Line

The drain line of your air conditioner may get clogged because of solid debris. Dust from the air accumulates on the evaporator coils.

When the dirt drips off into the water, it may form a clog. Also, the debris may come from algae or mold growth.

Here is a simple step-by-step process of unclogging the drainpipe of your air conditioner.

  • Turn off the entire system to prevent harm from the electric current.
  • Empty the drain pan of all its contents.
  • Check the opening of the drain and surrounding areas for any solid debris. If there is debris, remove as much as you can. You can use a simple wire brush to remove all the solid debris from the drain line.
  • Pour a full cup of vinegar into the drain pipe and the drain line. The vinegar will effectively dissolve all the mold and algae that may have grown inside your drain line. Uncontrolled mold and algae growth are one of the main causes of clogging in air conditioners.
  • Replace the cap on the top of the condensate drain line of your air conditioner. Test the system for any further drainage problems.

How to Prevent the AC Line from Leaking Water Inside 

It is possible to prevent an AC line from leaking water inside. This is necessary because leakages in an AC unit can cause severe water damage.

Here are a few things that you can do to keep your air conditioning system free from internal leakages.

Replace the AC Filters

Air filters trap all the contaminants before letting the clean air through. Air filters accumulate dust and other particles over time. You need to check the air filters of your AC unit regularly.

If they are old and full of dirt, you may have to replace them. Regularly replace the AC filters of your air conditioner to prevent standing water from inside your system.

Cleaning the Air Vents

Cleaning air vents regularly can go a long way in preventing excess water from forming in your air conditioner’s interiors. Air vents allow the cool and clean air to move around the home freely.

However, they do get full of contaminants after some time. Therefore, it is advisable to clean the air vents and keep them free of dirt.

Also, having clean air vents can encourage the smooth passage of air around the home.

Inspect the Drain Pan

Inspecting the drain pan of your air conditioner is an effective method of preventing excessive water drips. However, your air conditioner’s drain pan may be wrongly configured.

This usually occurs during the installation process. You can determine whether this is a problem by inspecting the drip pans of your AC units.

Correctly Completing the Installation Process

If you complete the installation process in a perfectly normal way, every component of the central air conditioning unit will function perfectly. The AC unit will lower your home’s air temperature and humidity levels.

Furthermore, the air conditioner’s drip pan will not be full of standing water. This is because it will be moving the condensate from the indoor unit to the outside.

How to Drain Water from the Air Conditioner

Here is how you can drain water from your window air conditioner.

  1. After unplugging your window AC unit, position it properly using a spirit level. Ensure that one of the ends of the level points towards the exterior of the wall. Let the other end of the level point towards the chassis.
  2. If your window air conditioner does not have a permanent drain pipe, insert one. You will have to locate the drain hole at the back of the chassis of your window air conditioner unit.
  3. Using a screw band hose clamp, connect a piece of hose to the drain pipe. The hose length depends on the position of your window AC unit and how far you want the hose to deposit the condensate.
  4. Collect the drain water from your window AC in 5-gallon buckets. This process may take a day or two, depending on the condensate available in your AC unit.

Here is how you can drain water from a portable air conditioner. It is necessary to drain your portable air conditioner when its drain pan and condensate line cannot clear the water fast enough.

Draining the water in a pan

After turning off the power, place a drain pan under the drain port. The drain port is at the back of the air conditioning unit.

Remove the drain plug and let the water flow freely for a while. Then, close the plug and power up your air conditioner again.

Draining in a sink or bathtub

  • Unplug your unit from the power supply.
  • Carefully carry it to a sink or a bathtub. This is necessary to avoid spillage.
  • Unplug your unit and let it drain freely into the bathtub or sink.
  • Carry it back to the power supply and switch it on.

Draining the water using a hose

  • Confirm from the manual that you can use a hose to drain your portable AC unit.
  • If this is the case, ensure the hose is secure on the drain port of the air conditioner.
  • Place the air conditioner on basement level so that the water moves down the hose by gravitational pull.


Your air conditioner produces water from the warm air that passes over its evaporator coils. The water drips to the condensate pan and then the drain line. If there is no water in your pan or line, the air conditioner is not working well. Similarly, a clogged drain line, damaged condensate pump, and low refrigerant levels can cause water to overflow.