Drain Lines Are Important Parts of an Air Conditioner That Need to Work Correctly

Last Updated on 08/08/2021

The AC drain line or condensate line is one vital part of an HVAC system and needs to be in perfect working order, for the cooling of the units to be effective. These lines are of great importance during periods of heavy cooling when outside temperatures are very high.

How does AC drain lines work?

When the air inside an AC is cooled, it results in the release of humidity that then condenses into water and needs to have an outlet which is what the drain line provides. These drains are made of metal or PVC and connect the cooling unit directly to the outdoors. The drains are meant to funnel the condensation away from the air conditioner. Most of these drains operate by gravity, though some ACs may even have pumps to do the job.

These drains lines must be of a diameter that will be effective in removing all the condensate water that form during the operation of the AC. A 3/4 inch diameter is considered adequate, and the piping must have a horizontal slope that needs to be in the direction of the discharge. A 1% slope is considered adequate. The drained water can be led into drains, sewerage systems, grassy areas or other suitable places. Make sure that this water drains away or evaporates easily so that this does not cause any other humid condition problems like mould and mildew or fungus.

A condensate or drain line helps to keep the humidity from building up inside the space being cooled. Moisture left unattended can cause the formation of mould and mildew and lead to poor health conditions. It can also lead to the corrosion of metal parts.

Most ACs have a drain pan that catches the dripping condensate and from here it evaporates into the air. Some ACs even have built-in systems that use this condensate to cool the unit and thus evaporate, though this technique is more commonly used in refrigeration units that are of the no-frost types. The warm air blowing over the cold evaporator coil makes the drainpipe quite humid and lead to ideal conditions for the building up of algae, that can add further to the clogging.

What happens if the aircon drain is clogged?

This drain line can get clogged by dirt and dust, and in some cases, the condensed water can turn into ice. Water then stops moving through it and leads to the build-up of moisture inside the air conditioner. Most of the newer ACs will shut down the unit if the drain line is blocked. The efficiency of the air conditioning unit will also reduce if drain lines are blocked. Some of the latest models of ACs also have sensors that will indicate that the drain line is clogged, and prompt you to take further action.

The blocking of the drain line can cause ice to form on the AC coils that then further goes into the drain line and adds to the clogging. Ice in an AC unit can cause severe damage to it. The drain pan can then overflow and spill the water into other parts of the air conditioner. It can cause pools of water on the floor that is close to the AC unit, leading to unsafe conditions, and also damage to carpets, and furnishings. Areas of the home can then suffer from water damage.

What can you do if your drain line is blocked?

You can always undertake to clear the drain line of its obstructions, if you equip yourself with some simple tools, and have confidence in your DIY skills. Start with the switching off the power to the unit and for further safety even removing the plug from its socket. Now locate the AC drain line, which will be in most cases locate outside close to the condenser unit. Push a stiff and thin brush into the open end of the drain line and clear it of any clogs or debris that it encounters. In most cases, such clogging occurs closer to the start of the drain line inside the unit. Use a vacuum cleaner to remove any dirt or debris that you have dislodged, by sealing the drain line and your vacuum hose so that when the vacuum is turned on it sucks out the clogged material.

Calling in the professionals will result in them following the same procedure, but with equipment that is ideally suited to and designed for the job, instead of any make-do solutions. These professionals will also clean up the vent tee that connects the drain line to the drainage tray. They may also use bleach or other liquids to completely clear the drain line. The cleaning of the drain line is something that must be carried out during every standard maintenance of AC units. It cannot harm to do this more regularly especially at times when the AC is being used for long periods of time and in hot and humid weather.

AC systems have to work for long hours and often for days at a stretch when homes are occupied and the weather is hot and muggy. The system also has to start and stop at intervals to maintain constant temperatures inside the cooled spaces. This continual and intermittent operation can lead to the breakdown of any equipment and more so if proper maintenance and care are taken of its important parts, of which the condensate or drain line is one. Preventive maintenance performed at regular intervals can go a long way in maintaining the efficiency of an air conditioning unit.

Key Takeaways

Local conditions need to be taken into consideration when deciding on the disposal of condensate water so that this added water to the environment in which your home is situated is not in any way affected by the drainage water. Never permit this water to get into crawl spaces or any other place like a driveway or sidewalk where it can become a nuisance. Constant inspection of the drain pan and operation of the drainpipe is important to ensure that your air conditioner is working to its required efficiency.