Spring has come early this year, and while the temperature change has been nice (and welcome), it’s a good reminder that the 2012 cooling season is nearly upon us. If you have an air conditioner, you’ll need to do some annual air conditioner maintenance to ensure that your AC unit works well, efficiently and remains trouble-free.
Don’t skip this step, even if it seems complicated. That’s because a central air conditioning unit can lose 5%-10% of its rated efficiency each year that regular maintenance isn’t performed. Within a couple of years, the high-efficiency air conditioner you paid a premium will provide lower performance than a well-maintained moderately efficient air conditioner!
Keeping your system clean is one of the primary ways in which you preserve the unit’s efficiency. Cleaning the unit means cleaning the condenser, which is outside, and the evaporator coils, which are inside your home. Neither of these tasks are difficult, and they’re certainly within reach of the DIY’er, but they do take a little time and effort, and you’ll need to have a good understanding of your heating and cooling equipment.
The outside condenser unit is covered with a metal case, which can be removed easily for cleaning. Before you remove the cover, you’ll want to cut the electricity to the unit at the circuit breaker. Once the unit is safely powered down, you’ll want to make sure that all organic debris (i.e., dead leaves, sticks, old grass clippings, nests, seeds, etc.) that may have found their way into the condenser unit are cleared away. This is also a good time to remove grass, weeds and other growth from the condenser unit to prevent this kind of material from entering the condenser unit later this season.
This is also a good place to point out that you may need to clean your condenser several times during the summer season. If you live near cottonwood trees, for example, they “seed” in June. Their cottony seeds float through the air like snow and will get sucked into your condenser. Any debris – including lawn clippings, petals from flowering trees, seeds and seed coats from landscaping – can clog your condenser and reduce its efficiency. Check the condenser regularly during the cooling season for debris. This will help keep your unit working at peak efficiency and can prevent premature failure for some components.
This unit is built for outdoor use, so you can use a hose and running water to clear out the condenser unit and the coils. Take special care to avoid damaging the “fins” or any delicate metal tubing you see in this unit. Make sure the drip pan (at the very bottom of the unit) is free from debris that can trap moisture and promote rust and other corrosion.
After you have the condenser unit clean, you can oil the unit if your unit requires it. Many units are self-lubricating or are sealed, so no additional lubrication is required. If your fan motor has oil ports, however, you’ll want to ensure that your unit is lubricated at least seasonally. You can do this by adding about 5 drops of oil to the oil port. Don’t use penetrating oil and don’t use an “all-purpose” oil. Instead, use the oil recommended by your manufacturer, or you can find lubricating oil for electric motors at your local hardware store.
Again, if the compressor motor requires lubrication, add a few drops through the oil port. (Check your owner’s manual if you’re not sure where the port is located, or if you need to lubricate your compressor motor.) Do not over-lubricate your unit.
If your compressor is belt-driven, inspect the belt for wear, glazing, cracking and signs of overheating. Also check under the motor for evidence of oil leaks. (Old oil will be dark and may pool under the compressor motor or at a connection point, or you may find evidence of oil spray buildup on the motor case.)
If you find evidence of a leak, chances are good that you’ll need to replace the motor. Unless you find a connection that is obviously loose, don’t attempt to tighten connections where you suspect an oil leak. Over-tightening can cause more damage to your unit and isn’t likely to solve your problem.
Check for coolant problems to the extent you are able. To do this, you’ll need to power on the unit. Adjust the inside thermostat so that the unit runs for about 5-10 minutes. Carefully move the insulation on the copper pipe that leads to the inside unit to expose the metal. The metal pipe should be cool (but not super-cold) to the touch. If the temperature of this pipe isn’t cool, call a professional to check the coolant level in your unit. Your unit may need to be recharged.
One more note on compressors: they’re not designed to work in cold temperatures, so reserve your unit maintenance until the outside temperature is in the 60°F-65°F degree range.
After you’ve checked for evidence of proper cooling, shut the unit back down and return the cover to its operating position.
In my next post, I’ll cover the inside work you’ll need to complete to make sure your air conditioning unit is ready for the cooling season.
If you have questions about air conditioner maintenance, or would like the pros at Boston Standard Plumbing & Heating to perform your air conditioning maintenance for you, please give us a call at (617) 288-2911 anytime and we’ll schedule a visit. Don’t forget to like us Boston Standard Plumbing on Facebook!