How to Spot & Prevent a Leaking HVAC System

Your Heating, Ventilation and Air Conditioning (HVAC) unit is probably one of the hardest working systems in your property. It is often used for months at a time, so it’s not surprising that faults sometimes occur. While regular maintenance can go a long way to preventing common problems and HVAC water damage, it’s not guaranteed to keep HVAC systems running smoothly.

We’ll explore the most common issues causing air conditioners to leak, how to fix them, and how to prevent them in future.

How do air conditioners work?

Air conditioning units have outdoor and indoor systems and use an evaporator coil to cool warm air. The combination of warm air and your evaporator coil results in condensation. In most cases, the air conditioning unit will ensure the moisture drips into a drain pan, which then goes through a main drain line to the outside of your property.

What is causing your AC leak problems?

Leaks are the most common sign that something is wrong with your air con unit.

There could be many reasons why your air conditioner is leaking water, the most common being:

  • Dirty air filters

  • Clogged drain line

  • Low refrigerant

  • The AC unit is old

  • Water in the outdoor unit

HVAC units can leak for many reasons, and knowing what might be causing yours is the first step to fixing the problem. We have a handy list of tips to prevent HVAC water damage in the future, once you’ve identified and fixed your current issue.

Is an AC Leaking Water Dangerous?

It can be. Water from an AC unit can leak into ductwork, pipes, brickwork, flooring, electrical circuits and power outlets. Routine maintenance is the best way to prevent this type of damage, but as soon as you spot any sort of water leak from your AC unit, turn off the system and your electricity until you can inspect the extent of the damage.

Too much condensation can also cause corrode various components of the system, increasing the potential for fires or explosions.

Top Causes of Air Conditioning Water Leaks & How to Fix Them

The Problem: Dirty Air Filter

Ideally, you should change your air filter every month because it has a lot of work to do, and when the filter gets dirty, it fails to perform. An air filter that isn’t functioning will put pressure on the rest of the air conditioning unit, which could cause parts to break.

Another issue with dirty air filters is the dust and grime will stop air flowing through, which could cause the coil to freeze. When it melts, water can flood the drain pan, which will affect your entire system and potentially cause water damage if it overflows.

The Fix

Changing your filter every month guarantees you’ll keep the whole air conditioning system working efficiently, but if you can’t manage once a month, then try to change it every two months.

The Problem: Clogged Drain Line

A clogged drain line is the most common issue we encounter with the average air conditioning system. As water flows through it regularly, the drain line can often accumulate dirt, dust, and debris – which means the water won’t be able to move through it, and the backup results in water coming through your home. This often causes water damage to walls and flooring, especially if not addressed quickly.

The Fix

Use a wet vac to see if you can remove the debris. In some cases, this will work, but if it is still not draining properly, it’s best to ask for professional support.

The Problem: Low Refrigerant

Your refrigerant is central to ensuring the air conditioning unit functions properly, and it needs to be at a healthy volume to maintain the correct pressure levels. When the pressure gets too low, the evaporator coil might freeze, which results in excess water.

Checking the refrigerant levels is the best way to see if there’s a problem, but you might also hear strange hissing noises coming from your AC system or notice that it’s unable to cool your room.

Air Conditioning Leaking Water vs. Refrigerant

When your air conditioner leaks, it’s common for people to view it as a mere inconvenience, and in most cases, it is. But there’s a distinct difference between an air conditioner leaking water and refrigerant leaks.

If your refrigerant leaks water, it can evaporate and turn into a gas which can be dangerous for your property. Luckily, there are ways to tell if normal water or refrigerant is leaking from your AC system.

Are Your Bills Increasing?

The best way to tell if your AC system is leaking refrigerant is to look at your energy bills. When the air conditioner is leaking water, the bills won’t change, but refrigerant leaks affect the system’s performance. Take a look at your electricity bill, and if there’s a distinct change in how much energy you’re using, it’s time to call in a HVAC professional.

Is There Water or Ice?

Another way to tell whether your air conditioning is leaking water or refrigerant is to look at the drain pan and coils. A full pan indicates a water leak, but ice on the copper lines and coils means it’s probably a refrigerant leak.

What’s Your Environment Like?

When your refrigerant leaks, your home will be warmer because the HVAC unit won’t function properly, and it can blow hot air into the house. Water leaks might be harder to spot, but many people notice a faint moldy smell due to the excess moisture.

The Fix

Some people attempt to repair the leak themselves, but you should only try this if you know how to do HVAC repairs. In most cases, it’s advisable to ask a professional for advice because you might need to change the entire AC unit.

The Problem: Damaged Condensate Pump

Some households have their air conditioning system in the basement, and it needs a condensate pump to filter the water outside. If the pump becomes damaged, it will fail to remove the water to the outdoor unit, which leads to your air conditioner leaking.

The Fix

Broken condensate pumps can be challenging to repair, but a professional engineer knows how to diagnose and fix the problems. In some cases, you’ll need to replace the condensate pump, but doing this will prolong the life of your AC system.

The Problem: Old AC Unit

Sometimes, there’s water leaking from air conditioning units because the system is old. Your AC system has a big job to do – and as it gets older, the parts will inevitably become less efficient.

The first problem you’ll probably notice is the drain pan, and if your HVAC system is 12 years old, you should replace the pan to see if it resolves the issue.

Pumps and pipes are also susceptible to damage, but in some cases, it might just be that the whole system needs replacing.

The Problem: Water in the Outdoor Unit

If your indoor unit is looking fine and your drain line isn’t clogged, check your outdoor unit for standing water, loose pipe connections and cover damage.

How to prevent HVAC water damage

Simple regular maintenance is the best way to preventing HVAC water damage and prolonging the life of your system, keeping it performing at its best and reducing costs for you.

Make time each month to check your filters, pipes and drains. It will only take a few minutes and could save you time, effort and cost in the long run. 

To give yourself a better chance of preventing AC leak problems, consider:

  • Installing a condensation pump to remove condensation from the unit and dispense it into the proper disposal drain. This also reduces the amount of standing water in the drain pan, helping it last longer.

  • Clean or replace your drain pan. A damaged drain pan can cause water leaks from your unit. Be sure to check and clean yours regularly to remove dirt, prevent mold growth and stop leaks.

  • Install a safety float switch. This will automatically shut off the HVAC system if too much condensation builds up, preventing water damage.

  • Fit a shut off switch to your drain line so that if it gets clogged, the unit will turn off and prevent further water buildup.

Why You Should Always Fix a Leaking HVAC System

If your HVAC leaks water, then it can still lead to severe consequences for your property. What might start with a few tiny drops of water can very quickly turn into a flood. Your attic or basement could suffer from severe water damage, and you’ll need to call specialists in.

Water damage can create a host of issues, especially if you don’t deal with it immediately. In most cases, your homeowners insurance will cover the cost of flood water removal and property repairs. The chances are, we work with your insurance company!

At iFlooded Restoration, we encounter this problem all the time and have a team of specialists skilled in water damage repair and restoration across New York. After fixing the problem and drying the room, we’ll do our best to restore your property to its original condition.