While a trained HVAC technician will always be the best inspector of your air conditioning system, there are many ways to self-check your home's system and its performance. Self checks can help you save money, potentially avoid an expensive service call or identify problems early while still within your warranty time limits. Many steps are common sense and once you have read our website you will be able to identify problems that can then be rectified through the air conditioning contractor who installed your system or your builder. These guidelines may be used in any sequence you choose.
1. Check your energy bills against your neighbors' bills. Comparisons with other homes in your neighborhood of similar size, floor plans and thermostat settings can be useful in identifying a home with problems. Large discrepancies on energy costs could point to air leaks, blocked ducts or other issues.
2. Measure and compare temperatures in the different rooms of your home after the air conditioning system has been cycling for some time. Your room temperatures should not vary more than three degrees Fahrenheit. A properly designed, installed and balanced air conditioning system should maintain even comfort throughout your home.
3. Your air returns should be clear and free of obstructions. Doors should be undercut or an air return in each space. When the system fan is running you should be able to feel some air movement when the door is held almost shut (just a two finger wide space between the jamb and the door). If you have doors that slam shut or are difficult to close (with system fan on) you may have pressure imbalance problems in your home.
4. Check your ducts; as described in the HVAC Basics. All ducts should have no kinks or restrictions, be fully extended with no excess lengths, have smooth turns, and be properly spliced with rigid metal internal couplings. You can see most splices by the use of tape in what seems to be the middle of long lengths of flexible duct. If you can compress this taped area easily with little resistance there is a possibility the duct was improperly spliced leading to system air flow losses that eat energy dollars. Your duct's external silver wrapper should be damage free with no tears that might allow cooling energy to escape.
5. ALL duct splices and connections should be properly sealed with NO leaks or gaps. This includes the connections to your air handling unit and coil located in your attic. You can often feel the air leakage with your fingers (assuming the air conditioning unit's fan is running) or a small piece of tissue paper held near the suspected leak with deflect with the air movement.
6. All drain pans should empty quickly through the primary drain pipe without any leakage over the sides. Make sure drains are not clogged and check the surrounding area for staining or signs of water damage. Your air conditioning system can produce a significant amount of water so drainage problems can lead to damaged ceilings or possible mold and health hazards. Make sure your drain pans are suspended at the proper angle to ensure its proper operation.
7. Your ducts and plenums (the square or rectangular metal boxes directly connected to the ductwork or air handler/coil equipment in your attic) should be properly insulated. Most areas in Arizona use the International Code Council statutes which require a minimum of R-8. Check the manufacturer's tag placed on the ductwork for the R value rating as illustrated in the HVAC Basics section of this website. Check with your builder or municipal building department to verify applicable building codes.
8. Check the coils on your external condensing unit for excessive dirt or obstructions caused by plants or debris. These delicate aluminum fins (looks like the radiator in your car) should not be damaged in any way and should only be cleaned per the manufacturer's recommendations.
9. Check the copper refrigeration lines coming from your outside condensing unit. The larger diameter "suction" line should be completely covered by the standard black rubberized "Armaflex®" or equivalent insulation and the seams closed or sealed. This suction line carries the cooling refrigerant into your home so cooling energy lost here never even makes it into your home.
These simple steps can save you $$$$! If you discover discrepancies using this checklist you should contact your builder to investigate your concerns. See also our "Consumer Rights" section. If you are currently building a home, you may take advantage of our "Free Rough-In Inspection" to prevent problems before they become trapped behind the sheet rock in your home.