There are two broad categories of air conditioners: individual room units (the kind usually mounted in windows), and central systems. Central air conditioners can be further categorized into split systems, in which the compressor/condenser is located outdoors, while the evaporator coil is inside the home;
and packaged systems, in which the entire unit sits outside with ducts carrying air to and from the house. In either type of central system, chilled air is blown through ducts (located either under the floor or in the attic), and into the living space through registers or grates.
An efficiently operating cooling system is critical to decreased energy use and increased comfort, particularly in warm climates. A well-maintained air conditioning system will use 15% to 40%
less energy than a neglected one. There are several Components in cooling systems that need to be properly maintained. Following the tips in this guide will extend the life of your cooling system, and keep it running smoothly and efficiently.
If you have central air conditioning or a heat pump and answer YES to any of these questions, cooling system maintenance is especially important for your home:
• Are you in a hot climate?
• Do you find it difficult to keep your home cool in summer?
• Does your cooling system experience frequent breakdowns?
There are some simple things you can do to make sure your cooling system operates smoothly; other actions require the assistance of a professional. With older and inefficient cooling systems, replacement is often the best option.
Clean or replace the air filter
( FREE or $, low skill)
Air conditioners will have an air filter to prevent dirt from building up on the cooling coils. Examine your unit's filter once a month during the cooling season, and clean or replace it when it appears dirty (which can indicate clogging). This alone can reduce your cooling energy use by 5% to 15%. Many filters are designed to be cleaned, but still may need to be replaced occasionally. This is an easy and inexpensive task that most homeowners can do themselves. Filters in room air conditioners are usually behind the front panel. Most split-system central air conditioners use the furnace's air filter. In packaged systems, the filter is generally found in the main "return-air" register.
Clean the condensing cooling coils
(FREE, medium skill)
Clean the condenser annually by following these simple steps:
1. Turn off the system at the thermostat, if possible, or turn the thermostat up to a setting that will not switch on the air conditioner. Also, turn off the power to the outdoor unit at the main breaker panel or at the disconnect located next to the outdoor unit.
2. Remove any loose debris from around the unit and clean it with gentle household soap and water.
3. Allow the outdoor unit to dry completely before turning on the power at the main breaker panel. After the main power has been restored, turn on the system at the thermostat or set the thermostat for normal operation.
Have a professional perform seasonal maintenance on central air conditioning systems
Air conditioner adjustments and repairs should be done by professionals. A professional service technician should clean evaporator and condenser coils, check refrigerant pressures, and adjust and lubricate moving parts. How often you need professional maintenance depends on how much your cooling system operates. For homes in hotter regions (where the air conditioner operates eight or more months per year), annual service is recommended. Cooling systems in warm regions (where the air conditioner operates five to eight months per year) should be serviced every 2 to 3 years. In colder regions (where the air conditioner operates less than five months per year), every 3 to 5 years is usually enough.
Replace the air conditioning system
In some situations it will make sense to replace an older air conditioner with a new, high-efficiency unit. Air conditioner replacement should be considered if the existing unit is worn out, inefficient, or significantly oversized. Repairing an existing air conditioner may seem to be the least expensive option, but it may cost more in the long run. Paying for repairs on an older, inefficient system may simply prolong the inevitable need for replacement. Installing a new, energy-efficient system may be much more cost-effective.
Sizing your air conditioner. Bigger is not always better when it comes to your air conditioner. For starters, oversized equipment can be less effective at dehumidifying your house. Not only can this lead to moisture problems in a home, but the higher humidity may force you to lower the thermostat to achieve the same comfort level—increasing your energy use. An oversized unit also cycles on and off more frequently, which increases wear and tear, shortens the service life, increases the frequency of repairs, and reduces efficiency. Plus, it costs more to purchase oversized equipment in the first place. If purchasing a new air conditioner, cooling loads should be carefully calculated by your equipment supplier.