Dogs are notorious for destroying your lawn and digging holes. But they can also do this to your air conditioner. For example:
Air conditioner damaged by dog urinating on it. Source: cspi2002 on YouTube
A dog (or multiple) decided to mark this air conditioner. And, as you can see, dog urine is quite corrosive.
If you have a newer AC, it likely has a heavy-duty protective grates. But even that won’t protect your AC from dog urine. It just hides it. Check out the AC below that was found by a home inspector.
Dog urine destroyed the coil under this AC’s grate. Photo source: Inspectopia
Damage like this can be expensive. Depending on the amount of deterioration, you have 3 possible outcomes:
Below, we’ll explain each of these outcomes in more detail and give some advice on when to choose each option. But first, you need to understand what it is that your outside unit even does.
The outside air conditioning unit’s primary job is to get rid of the heat your AC collected from inside your home. Here’s how it works:
Related: How an Air Conditioner Works
Diagram of an outside AC unit from Inspectapedia.
Now, attached to the condensing coil are aluminum fins (that’s the grey part you see in the photo below). These fins help improve the AC’s energy efficiency by increasing the surface area of the coil. Increased surface area helps the coil dump the heat faster.
Damaged outdoor AC unit showing fins. Original image source: cspi2002 on YouTube
Now, let’s look at the different possible outcomes from dog urine damage on this outdoor unit.
If only a small area of aluminum fins (less than 25%) are damaged and the coil is not leaking, you may choose to just leave your AC alone for now.
While the fins are important (they increase energy efficiency), missing some of them doesn't make the air conditioner inoperable.
So long as you do something to keep your dog from making the damage worse, your AC should continue to work fine. Of course, you will have higher AC bills. But they will likely be less than the cost of a new coil or unit.
Cost of damage: 2-10% decrease in energy efficiency
But if there’s damage to the coil itself, you may need to...
The condensing coil is the metal tube you’re seeing when the fins have disintegrated.
Damaged AC showing condensing coil. Original image source: cspi2002 on YouTube
As we mentioned before, the condensing coil’s job is to get rid of the heat your air conditioner absorbed from inside your home.
You should replace the coil when dog urine has caused extensive damage to the coil or more than 25% of the fins are missing AND:
Cost of damage: $600 to $2,000+ to replace coil
But sometimes you have to...
Replacing the whole outside unit is usually the best option when the coil needs to be replaced and at least one of the following is also true:
Cost of damage: $1,500 to $3,000 to replace outdoor unit
As you can see, dog urine can cost you hundreds—or even thousands—of dollars. Luckily, the solution is easy: keep your dog away from your air conditioner by installing a fence around it.
Caution: Most air conditioner fences are installed incorrectly. If the fence blocks airflow to the air conditioner, your air conditioner will work less efficiently. For that reason, we recommend that your fence be:
Here’s a good example we found at Lowe’s:
No Dig Powder-Coated Steel Decorative Metal Fence Panel from Lowe’s
Coolray is a home comfort expert with specialists in heating, air conditioning, air quality and plumbing. We serve communities throughout metro Atlanta, Birmingham, AL and Nashville. Have more questions? We’d be happy to help – just contact us online.
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