Frozen air conditioning? Here’s why – and what you should do

  • aircon service and repair

Help, my air conditioner is frozen!

It sounds weird, we know, especially for homeowners in sunny Brisbane – it probably sounds like more of a Melbourne or Hobart problem than something that happens up here.

It may not be the most common issue, especially up here, but it’s still entirely possible for the temperature to get so low that parts of your air conditioning system freeze.

However, that’s not all we mean when we say “freezing”. There are a number of specific air conditioning issues that can cause it to stop working (or, to “freeze”). So while the term pertains to weather, it can also include a number of other factors – which you’ll see below. 

And if your system starts to freeze, you might notice a number of other issues popping up – you’ll need to address it immediately with aircon service and repair if you want to prevent lasting issues with your system.

Is a frozen AC unit dangerous?

Fortunately, this isn’t one of the aforementioned long-term issues that can arise with a frozen air conditioning unit.

That having been said, just because it doesn’t pose a danger to you or your family doesn’t mean that there’s no danger – it’s just that all of these dangers are directed at your system:

  • Compressor failure and burnout
  • Fan damage and damaged coils
  • Complete system failure (if you keep running it)
  • Damage to adjoining components

Remember that water expands when it freezes. This can result in many of your A/C components being moved and pushed around, or pressure being applied to sensitive parts, leading to damaged components.

While this may not pose a danger to you, it will pose a danger to your wallet – in many cases, the repair bill can be as high as the deposit for a new system altogether!

And of course, you can’t forget about the impact that it’ll have on your power bill.

The best way to avoid all of these different issues? By scheduling aircon service in Brisbane.

What causes an AC unit to freeze up?

Like we said above,we’re not always talking about low temperatures when it comes to your air conditioning unit freezing up.

In these instances, “freezing” also refers to specific cooling components of your aircon malfunctioning, causing your unit to literally freeze up.

These are some of the most common problems…

A blocked filter

Clean filters are crucial for your system, protecting you from airborne debris and dust. Of course, if you don’t clean your filters on a regular basis, they might get blocked.

In addition to issues like unwelcome smells and impaired airflow, a blocked filter can also result in a frozen AC unit.

Essentially, a blockage stops all of that cold air from making it out of your system and into your living areas. Instead, all that cold air builds up, which can lead to the moisture in your system freezing up.

And it isn’t just filter blockages, either – any sort of airflow issues such as fan problems are also liable to cause these types of issues.

Low refrigerant levels

Not only will a refrigerant leak impact your system’s ability to keep you cool, but it can also result in a frozen system!

That’s because your system is designed to operate with a full tank. When your refrigerant levels drop, it has a number of effects, one of which is your system essentially “overcooling” itself, leading to frozen components.

The actual reason is a lot more technical than that, but this gives you the general idea!

Unfortunately, this isn’t a fix you can perform on your own. For starters, they don’t exactly sell air conditioning refrigerant down at your local hardware store – the other thing to consider is the fact that refrigerant is dangerous, and liable to cause burns if it comes into contact with skin.

If you’re worried about refrigerant levels, the best thing you can do is arrange ducted air conditioning repairs – we’ll take a look at your refrigerant levels and top your system up.

Can a clogged drain cause AC to freeze?

While this one is rarer, it can on occasion lead to a frozen air conditioner unit.

Your drainage line is essential for preventing moisture build-up inside your system. When this line gets clogged, you’re left with a lot of water and moisture stuck inside your air conditioner, increasing the risk of freezing.

Sometimes, it can build up to the point where it actually backs up inside your condenser, where it is liable to freeze thanks to the extremely low temperatures while your system is operating.

Not only that, but there’s also the risk that your drain lines themselves can freeze over if there;s even a partial blockage!

ducted air conditioning repairs

Cold temperatures

And finally, cold temperatures can result in moisture in your outdoor unit freezing on particularly frosty nights.

Luckily, the vast majority of systems are designed with insulation to prevent this from happening (as well as to prevent overheating during summer).

Not to mention, it almost never gets cold enough for this to happen up here in Brisbane – this is more a concern for people living in alpine areas, or places with regular snow.

How do I unfreeze my AC unit? Will a frozen AC fix itself?

Now that we’ve gone over the causes of a frozen system, it’s time to start talking about what you can do to unfreeze your system and get it working again.

The very first thing you should do if you suspect that your system is frozen is to shut it off – as we’ve said before, trying to force a frozen A/C to run while its components are frozen can actually cause a whole load of other issues.

But what about afterwards?

How long does it take for AC to unfreeze?

In many cases, you might be able to resolve the freezing issue (temporarily, at least) by simply leaving your air conditioner to thaw.

While it means you may have to go without cooling for the time being, it can help prevent permanent and lasting damage. Not to mention, this particular remedy is free and easy to do!

And while you’re at it, there are also certain maintenance tasks you can perform in the meantime to prevent future freezing. While you need a special license to safely handle air conditioning refrigerants, there’s no licensing requirement for cleaning air conditioning filters or unclogging a drain line.

The exact amount of time you’ll need to set aside will depend on the extent of your freezing as well as ambient temperatures. Once that’s done however, the next thing you’ll want to do is dry your system out by running it on the fan setting.

After that, you should be good to go.

Can you pour hot water on a frozen AC unit?

If it’s a cold day out or it’s taking longer than expected to defrost your system, you can take things into your own hands by pouring hot water onto your system.

Don’t worry, this is a completely harmless way of speeding up the defrosting process!

Just remember that your outdoor unit is, well, installed outdoors. As such, it’s designed to be waterproof and resistant to rail – assuming that its waterproofing is still in good condition, there should be nothing wrong with using a little bit of warm water to speed up the thawing.

Of course, this isn’t the only technique you have to help turn your system from a popsicle back into a functioning air conditioner – while it isn’t all systems, many come with a built-in “defrost” mode that’s designed specifically to speed up the thawing process.

If your system is one of them, it can be worth turning this on as well!

Just be warned that all hot water (and defrost mode) does is help thaw your system – unless you address the root cause behind your freezing issues, you can expect them to return further down the line.

I think my AC has frozen – what should I do?

The above steps can help you defrost your system, restoring its function and preventing the lasting damage that comes with running a frozen aircon.

Of course, not all air conditioning problems – freezing or otherwise – are caused by something that’s easy-to-fix like a clogged filter. Other times, it could be a much deeper issue.

In cases like this, the only thing you really can do is get in touch with a professional.

Our heating and cooling specialists are here to do one job: keep you comfortable. With our experience, skills and training, we’re able to look after your comfort, fixing any issues that might be making your home feel unnecessarily hot.

Whether you need Daikin aircon service, Mitsubishi Electric tech support or advice for an upcoming project that involves an upgraded AC unit, we’re ready to help. You’ll be able to rely on more than 30 years of experience working on air conditioners of all shapes, sizes and types throughout Brisbane.

All you need to do is get in touch today on (07) 3394 0222, or click here to receive a quote.

2024-04-26T01:28:05+00:00 6 April 2021|Service, Systems|