Keep your air-conditioner (AC) maintained will not only save you money but also energy, but you’ll also extend its lifespan, saving money on expensive early replacement. Your Heating, Ventilating, and Air-Conditioning system (HVAC) will consist of either a heat pump, a furnace and AC, which cools and heats. Both types will have an interior unit (evaporator and blower) and an exterior unit (condenser coil and compressor). These instructions apply to a whole-home air conditioning or heat pump unit.
SHUT OFF THE POWER
Due to the dangers of working around electricity and the air-conditioner’s moving parts, it’s essential to completely shut down the unit. On the exterior condenser/compressor, look for an exterior shut-off box near the unit. Indoors, also shut the power off at the breaker box.
REMOVE THE DEBRIS
On the exterior condenser/compressor, remove the fan cage. Using a screwdriver or wrench, remove the fasteners and lift the cage or fan grill away from the top of the unit. By hand, or with a wet/dry vacuum, clean leaves and other debris from the interior.
CLEAN THE FINS
With a strong stream from a garden hose, spray through the fins from the inside out to blast any built up dirt or debris from between them. Never use a pressure washer, it may damage the fins. If the fins are particularly dirty, use a commercially available fin cleaning spray (available at home improvement centers; must read and follow manufacturer directions).
STRAIGHTEN THE FINS
Since any reduction in air-flow through the fins can reduce efficiency, carefully straighten bent fins using a butter knife or commercially available fin-straightening tool. Be gentle so that the tubing embedded within the fins will not damaged.
CLEAN AREA AROUND THE UNIT
Once done with the cleaning, replace the fan cage. Rake back leaves and debris outside the condenser and remove back branches and vegetation 2 feet at least in all directions to ensure proper airflow around the unit. During winter months when the condenser is not in use, it’s good to cover the top of the unit with a piece of plywood or plastic to keep debris from falling in. However, do not completely cover the side of the units, causing corrosion and moisture can build up inside.. Also, a completely covered unit encourages vermin to build nests inside. Take the cover away when the unit is operating.
LEVEL THE UNIT
Over time, the pad upon which the condenser unit sits may start to tip as the soil settles beneath it. Out-of-level condenser unit may cause the compressor within to fail early. Always check the condenser for level and use rot-resistant shims to bring it back to level.
CLEAN THE EVAPORATOR COIL
On the inside blower/furnace unit, find the evaporator coil door. You may need to remove some foil duct tape and take out a few screws or bolts. Inside, use a soft brush to dust off the coil, then spray the coil with commercially available no-rinse coil cleaner (available at home improvement stores). The spray will foam up and then drip into the drain pan. Clean out the drain pan with soap, hot water, and a little bleach. Then, pour a cup of 50% bleach/50% water down the drain. To keep the drain clear longer-term, place a commercially available drain pan tablet in the pan. This will inhibit future algae growth.
CLEAN A PLUGGED EVAPORATOR DRAIN
On the interior, warm, humid air from your home’s interior is blown through the evaporator coil. The cold coil absorbs heat from the air, cooling it, before the air is circulated back into your home. The humidity in the air condenses on the cool surface of the evaporator coil as liquid water, dripping into a pan below. From the pan, the water flows into a drain tube which is typically routed into a basement floor drain, utility sink, or outdoors.
CHANGE THE BLOWER FILTER
The filter in your HVAC system should be changed at least every six months – once just before the heating season begins and once before the cooling season begins. If you live in a particularly dusty area, you may want to change it more often. Always replace the filter with a new filter that has the same airflow rating. Again, Moody cautions, Be careful with ‘air purifying’ or HEPA filters, because they can dramatically reduce airflow in your system. That can cause the indoor coil to freeze because of the reduced airflow.
TURN THE POWER BACK ON
While these steps will help to keep your AC system in top shape, be cautious that there are maintenance items that only a trained and skilled HVAC technician will be able to perform. For an instance, a slow refrigerant leak in your AC system may lead to expensive compressor failure, but a homeowner does not have the tools or skills necessary to check refrigerant levels. Also, clean ducts and proper airflow are important factors to a well-functioning system, but homeowners lack the necessary equipment for the job. The bottom line? While some AC maintenance can be perform by a savvy homeowner, it’s still important to have an expert technician check the system from time to time.