AC Maintenance: Taking Care of Your Outdoor AC Unit in Richmond, Texas

AC maintenance is one of the easiest ways to keep your air conditioner in tip-top shape and running as efficiently as possible in Richmond, Texas.

We often get questions about the best way to maintain outdoor AC units. If you have a central air conditioning system, the outdoor unit is also called a condenser or an AC condenser. The condenser can also be your heat pump.

Why is it important to clean your outdoor AC unit?

An outdoor AC unit has metal fins as part of the outdoor coil which transfers heat into the surrounding air. As part of the refrigeration process, the outdoor unit needs to be able to breathe to work properly. The coils have to be able to exchange heat.

If your outdoor unit is clogged with overgrown vines, pollen, leaves, dust, feathers, grass clippings, or dirt, it will reduce the air flow across the coil and make it much less efficient.

When it’s really hot during the summer, the coil will run a lot hotter than usual and it will lose its maximum cooling capacity. Increased airflow is a must to properly remove the heat and ensure the refrigerant condenses back into a liquid.

If clogged, the outdoor AC unit can overheat and shut down. It can cause parts to wear out more quickly.

When left unaddressed, it is one of the top five killers of a compressor. Clogged condensers shorten the life of your AC unit and cause your AC to work less efficiently, leading to higher utility bills.

How often should someone clean the outdoor AC unit?

We recommend cleaning the outdoor unit once a year with water. Cleaning it a lot more often can risk mineral scaling on the condenser’s coil from your water. Mineral scale is an insulator, which means the coil will lose its capacity to transfer heat.

In most cases, we don’t recommend using chemical cleaners for your outdoor AC unit very often unless it’s exceptionally dirty. Once or twice is fine, but I don’t recommend making a habit of it each year.

The reason is that these chemical cleaners etch the aluminum and/or copper, making coils thinner over time. The more often chemical cleaners are used, the higher the risk the coil is for a refrigerant leak or coil failure.

Another reason you might need to clean your outdoor AC unit is if you have Cottonwood tree blooming nearby in the spring. Their fluffy seed pods look like cotton floating on the air. These can clog up an outdoor ac unit quickly, so be aware if you have a tree or bush with similar attributes.

When is the best time of year to clean an outdoor AC unit?

Making sure landscaping is not encroaching on your outdoor AC unit can be done during our long growing season here on the Texas Gulf Coast. Vines and weeds can grow quickly, especially after a good rain.

Otherwise, we recommend spraying water from a hose to loosen up and remove dirt on those delicate aluminum fins in the spring, around the time that you’d schedule routine AC maintenance.

How can I clean an outdoor AC unit step by step?

1. Flip the power off – Turn off the power to your AC for a short time and pick a day that is mild if you can.
2. Cut back landscaping – Trim landscaping away from the outdoor unit. The aluminum fins on the outdoor AC unit are delicate, so take care if you are using a string trimmer. Make sure there is two feet of clearance around your outdoor AC unit.
3. Use a garden hose – Use a regular garden hose and shower head nozzle spray attachment or your thumb to create a gentle spray. Spray the outside of the AC unit with water starting at the top, moving left to right, then working toward the bottom.
4. Restore the power – Once the job is complete, you can restore the power.

What not to do when cleaning an outdoor AC unit

Occasionally, we see damaged outdoor AC units because a DIY cleaning went wrong. When in doubt, we recommend asking a licensed HVAC technician for advice.

Here’s some tactics to avoid:

1. Don’t use power washers – Do not use a power washer to clean your coil because it can damage the aluminum fins.
2. Skip fin straighteners – We do not recommend anyone using a DIY fin comb or fin straighteners to fix any sections of the fins on the coil that have been flattened. Every manufacturer has different spacing, so one comb does not fits all. Avoid any fin straightener power tools. Trust me on this one.
3. Avoid chemical cleaners –  Extra outdoor ac unit chemical cleaners are generally not necessary *unless* there are special circumstances. We certainly don’t recommend using them each year because it will shorten the life of your system. Each time they are used, a little more metal gets etched away.
4. Watch for water not penetrating the coil – Ask a licensed AC technician for advice if you’re spraying the condenser and the water isn’t going all the way through. Older and larger condensers may use a double-row coil that is stacked making it difficult to see water penetrating the coil.
5. Don’t restrict the air flow above the fan – We have seen people use shade cloth or other similar materials placed over the top of the outdoor ac unit to keep the leaves out. This can restrict air flow, which is why we don’t recommend it.
6. Avoid adding umbrellas – Adding an umbrella to shade an AC unit in a long-term way seems like it would help on a very hot day. The reality is that an umbrella held over the top of an outdoor AC unit can concentrate and recirculate the very warm air around your outdoor AC unit, making it harder for your AC unit to disburse the heat it’s collecting indoors. Over time, it can make your AC unit work harder.

If you see these warning signs, your outdoor AC unit may need to be cleaned

The easiest way to tell if an AC unit should be cleaned is to go to the outdoor unit and put your hand and arm 6-12” above the fan. If the air coming out it is about to burn you within 30 seconds to a minute, chances are your coil is running too hot. It’s either a dirty coil or needs another necessary repair.

If your outdoor AC unit has never been cleaned or maintained as part of regular service, consider scheduling an AC tune-up. Our premium AC tune-up includes cleaning the outdoor AC unit as a task on our checklist. Regular maintenance visits often prevent AC breakdowns and give you time to ask maintenance questions.

Another warning sign is if you can see the overgrowth of vegetation across your outdoor AC unit. This is a good indicator to trim it back.

When to call a licensed professional about your outdoor AC unit

We recommend preventative ac tune-ups twice a year, in the spring and the fall. We include outdoor AC unit cleaning as part of our premium AC tune-up checklist. If you’re not sure if it’s included, feel free to ask.

More reasons to call a professional:

1. Ice – If your outdoor ac unit is frozen up and you can see ice, it can be an indicator of poor airflow or low refrigerant levels. A licensed AC professional will be able to help.
2. Rust and bent fins – If you see a lot of rust or can see a lot of bent fins on your outdoor AC unit, this is a sign that a professional should be called.
3. Exposed wires – If you see a lot of exposed wiring near the fan motor or anywhere on the outdoor unit, call an AC technician for advice.
4. Burning or bad smell – If you see anything that smells burnt, an AC professional can determine if there is an electrical problem or a problem caused by a rodent or other critter.
5. Oily stain – If you see an oily stain on the side of your outdoor condenser, it could indicate a refrigerant leak. For safety, those are best addressed by licensed AC professionals.
6. AC Not running – If your AC is not running at all and/or the outdoor AC unit is not running or blowing out warm air, this is important information to share with your favorite air conditioning and heating company.

Knowledgeable Care for Your AC in Richmond, TX

In Richmond, Texas, our family has been keeping fellow homeowners and business owners cool since 1982. Call or text Rob and Summer at Terry’s A/C & Heating at (281) 495-7830 to set up an appointment for an AC tune-up or a repair. We also offer an AC preventative maintenance program we call our Peace of Mind Protection Plan.

We are based in Richmond, Texas and serve most of Fort Bend County, Katy, Sugar Land, Fulshear, Rosenberg, Southwest Houston and points nearby. We were named one of the best HVAC companies in Richmond, Texas, according to the Fort Bend Herald’s Reader’s Choice Awards. See our story and read more tips on our blog.