5 Reasons a Ductless Mini-Split May Leak Water

Ductless mini-split systems are an excellent solution for room additions, finished attics, converted garages, and for homes that simply do not have central air.

Due to their zone climate control, quiet operation, and unobtrusive design, it can be easy to forget that yours is operating — until there’s a leak. While a common problem, a mini-split that is leaking water needs to be addressed promptly to prevent water damage, mold growth, and further damage to the unit.

How Ductless Mini-Split Systems Work

Before you try to determine why your mini-split system is leaking, it’s important to understand the major components that make up the unit and how they work.

A ductless AC mini-split system is comprised of two main components: the indoor unit that is operated with a remote control, and the outdoor compressor or condenser.

Much like a traditional central air system, the indoor unit takes in warm air from a room and converts it to cool air by running it over a series of evaporator coils filled with refrigerant. The cooled air is then pushed back out to be circulated throughout the space.

The indoor unit connects to the outdoor condenser through a refrigerant line, a power cable, drain lines, and suction tubing. The refrigerant that has been warmed by the air indoors is transferred to the outdoor condenser to be cooled again.

When a mini-split system cools the air, excess moisture turns into condensation inside the unit where it is removed through a drain line or pump and directed outside.

Why is My Ductless Mini-Split Leaking Water?

Sometimes, a mini-split system can encounter water leakage issues. Let’s review some of the most common causes.

  1. Blocked Drain Line: Mini-split condensation can contain small amounts of dirt, debris, or even mold that can build up over time, resulting in a blockage in the drain line. As the blockage worsens, it becomes difficult for the system to direct the condensed water out of the indoor unit, resulting in the indoor unit dripping water.
  2. Damaged Drain Pan: Excess water collects in the drain pan, where it is directed to the drain line. Over time, wear and tear or corrosion can weaken the drain pan, causing water to leak from the unit.
  3. Dirty Filters: Over time, filters can become clogged with dust, dirt, pet hair, and other debris. As air struggles to pass through the filter, the system’s airflow is impeded, leading to decreased efficiency. The reduced airflow hampers the mini-split’s ability to regulate temperature effectively, causing the coils to become colder than usual. When humid air hits the frigid coils, condensation begins to forma and can eventually overflow, leading to water leaks.
  4. Low Refrigerant: As the refrigerant cycles through the system, it alternates between absorbing and releasing heat, resulting in cooler air. Inadequate refrigerant levels can cause the unit’s coils to not reach the desired temperature during the cooling cycle. As a result, when moisture-laden air comes into contact with the coils, condensation forms, and the unit struggles to handle the excess moisture. This can lead to the mini-split dripping inside, followed by external leaks.
  5. Leaking Refrigerant: The leakage from a mini-split unit might not always be water—it could be refrigerant. The potential health hazards associated with refrigerants underscore the critical importance of promptly involving a trained professional to address the matter.

A small water leak might not always escalate to an immediate emergency unless the AC is spraying water or gushing. However, it’s important not to underestimate the potential consequences. If you notice water leaking from your ductless mini-split, turn the unit off and contact Air Professional Associates right away. A small water leak doesn’t always signify an emergency, but it’s important not to underestimate the potential consequences. Call us today or anytime for all your heating and cooling needs.

Air Professionals Provides Service In These and Other
Nearby Communities