When it comes to air con fault finding, trying to figure out why your air conditioner is leaking water is one of the most frustrating. Air conditioners are complex machines with a lot of components, creating multiple possible sources for a leak.
Getting to the bottom of the problem takes a detailed investigation, and because air conditioners are electrical appliances, this should ideally be carried out by experts. However, this doesn’t mean you can’t carry out some superficial investigations of your own. There are some simple fixes that you can work through, and possibly save yourself the cost of hiring a specialist.
Let’s kick things off with a few things to look for if you’re worried about a leak.
Signs your air conditioner is leaking water
So, how do you know you have a leak? Unfortunately, not all leaks will announce themselves loudly and proudly, and while you might catch one early and be able to trace it back to its source with ease, keeping an eye out for more subtle clues will serve you better in the long run.
A waterfall gushing from your air conditioner is probably a pretty clear indicator that it’s time to get a replacement sorted, but before it gets to that, be sure to look out for:
- A mouldy smell in the home
- Water spots and water damage, especially around units, ducts, and piping, and up on the ceilings
- Stagnant water around the unit
- Reduced performance
- Dripping sounds
Now you know what to look for, let’s explore some of the most common reasons why an air conditioner leaks water, and what you can do to manage them.
1. Outdoor condensation
Some leaks are unavoidable and – happily – a non-issue. In a humid state like Queensland, it’s perfectly normal for a small amount of condensation to drip from your unit, especially for older box air conditioners which drain from the outdoor unit one drop at a time.
So, if you see drips from the outside unit of your box air conditioner, don’t panic. Inspect your air conditioner carefully and ensure that there’s only a small amount dripping from the correct drainage hole. Check carefully for any signs of rust, internal leaking, or water coming from areas it’s not supposed to – if you do find any of these, stop using your air conditioner immediately and hire a professional to take a look.
2. Rusty drain pan
Rusty drain pans are a common cause of air conditioner leaks in Queensland, as the high humidity creates the perfect condition for rust. It’s also common in seaside or estuarine suburbs, where salt carries on oceanic breezes before being ingested by air conditioners.
When the air conditioner’s drain pan rusts, its base weakens and holes will eventually form. The pan will then fail to collect water, and any internal condensation will simply leak out of the unit. In those cases, a replacement drain pan is in order.
In general, it’s very important to ensure that rust isn’t affecting any parts of your air conditioner. It can be fatal to air conditioner units, and any sign of rust (including in the drain pan) could well be an indicator that your current air conditioner is on the way out.
3. Clogged drain pan
Rust isn’t the only enemy of your drain pan – clogs and blockages can degrade them too. When the drain pan clogs, it can cause a large build-up of water and eventually overflow, often resulting in more sudden and serious leaks.
Clogs are usually a simple fix, but it depends on the circumstances. In some cases, you’ll need professional help to clear out and identify the cause of the blockage. Knowing the cause of the obstruction is important, in case it turns out to be a symptom of a more sinister wear and tear.
Occasionally, drain pans are blocked by small air conditioner components that perish within the system and fall into the drain pan. When that happens, it’s a good sign that your air conditioner needs serious professional maintenance.
4. Disconnected drain line
The air conditioner’s drain line is the first and last line of defence against serious leaks. It ensures that all moisture and condensation is drained out of your air conditioning system in an appropriate and manageable way. Needless to say, if it’s disconnected, your air conditioner will leak like a sieve.
If you can safely access your drain line without dismantling or disassembling the unit, then you should check to ensure that it is still attached to the drainage outlet. You should also check to see that it’s in reasonable condition. It’s uncommon for the lines to loosen, but it can occur and often does when inexperienced or unqualified individuals perform air conditioner services or installations.
5. Poor insulation
For anyone with a ducted system, keeping an eye on the insulation around your air con is an absolute must. The insulation works as a barrier between your home and any leaks that might occur. Check regularly for any breaks or any spots that might have worn away and get them fixed up as soon as possible.
6. Clogged condensation line
When your air conditioner removes water vapour from the air, that vapour condenses in the condensate line. If all is working well in your system, then it should transport that condensate through the drain line and out of the system. However, if there is debris present within the condensate, then that can accumulate over time into a major obstruction. In serious cases, it can cause the condenser line to rupture, which then causes serious leaks.
Any issues involving your condenser line will require fast and professional attention. If you are noticing leaks in your system, stop using it and get an expert to take a look.
7. Damaged or dirty coils
Air conditioners in Brisbane need an annual service, plus regular maintenance to remain at their best. Part of that maintenance should include coil cleaning, as mounting dust and debris disturbs the thermodynamics of the coils and can cause condensation in the wrong areas. When that condensation creates ice, you’ve got a problem.
Damaged or dirty coils can cause leaks in air conditioners and might also be a sign of much worse to come. In a lot of cases, ice develops on coils that are not properly cleaned or maintained, and, as you’ll see, this can be incredibly damaging to your air conditioner.
8. Icy evaporator coils
Icy evaporator coils are one of the most common causes of air conditioner leaks, and they’re usually a result of overuse and humidity. When you run an air conditioner non-stop for a long period, humidity can condense within the unit and build on the evaporator coils, before freezing. That only compounds the problem, as more moisture condenses over the coils before freezing and builds into a block of ice. When enough ice amasses, the outer layers will melt and refreeze. This creates an ongoing cycle, causing icy water to leak out of the unit.
A lot of the time, you can fix that by simply turning off your air conditioner for a while and letting it defrost. However, there’s a chance that a leak somewhere else in your unit has caused the icy build-up, in which case it will continue to recur until you find and fix the underlying leak or replace the entire unit. When you see ice, it’s important to stop running your air conditioner, because doing so can seize your compressor pump and potentially destroy the entire unit.
There are two main reasons why you might start to see ice on your condenser coils.
1. Blocked air filters
Air conditioner maintenance 101: keep your filters clean! If an air filter becomes blocked, air flow through the air conditioner is restricted. This means that the only places that are going to stay cool are the condenser coils – and we’ve just seen what can happen if they’re left to chill for too long.
Checking, cleaning, and, if needed, replacing your filters every couple of months can help stop this from happening. If it’s been a while between check-ups, or you’re dealing with a particularly large and complex system, consider bringing in a professional to make sure you’re set up for success.
2. Low refrigerant levels
Another issue that can lead to iced over coils is low refrigerant levels. This can often be exacerbated by high humidity, clogged filters, or overuse. Less refrigerant means faster evaporation. This leads to the unit cooling faster overall, making ice more likely to form.
Given that refrigerants can be dangerous if handled incorrectly, it’s important to have this issue dealt with by a licensed professional. They can check the levels, top up if needed, and also see if there’s a particular reason the levels have dropped so low.
So how can you stop leaks from happening?
The best answer is probably the most obvious – take good care of your air conditioner!
- Build a solid maintenance routine – you can start right here, with our handy guide to cleaning your air conditioner – and get to know what’s normal for your machine.
- Keep an eye on the space around the unit in case any of the smaller signs of water damage begin to show.
- Schedule in regular yearly inspections with a licensed professional and nip any issues in the bud.
- Don’t overwork your machine. Though it might be tempting to run your air conditioner morning, noon, and night during those humid summer days, overworking your unit is a sure-fire way to push your air con (and your bills) into dangerous territory.
And, of course, if in doubt, call in a professional to take a look!