HVAC Frequently Asked Questions
Our answers to frequently asked questions are broad generalizations, and are provided for entertainment purposes only. Watkins Mechanical, Inc. cannot be held liable for damages resulting from use of this information.
Air Conditioner FAQ
- Why is my indoor A/C coil/pipes/compressor covered with ice?
- A frozen indoor coil indicates that the refrigerant level is low, or the air filter is clogged. In either case, the coil will get colder & colder until the condensation on the coil turns to ice. This condition can be very harmful to the air conditioner, and is a common cause of bad compressors.
In the event of a freeze-up, turn the system off. Check the air filter. If the filter is not clogged, the air conditioner probably needs service.
- Does my air conditioner use freon? Is freon "illegal?"
- The current law prevents the use of R-22 in NEW systems after 2010. The law also caps production of R-22, and will result in higher prices as supply tightens. R-22 should be available to service your air conditioner for a long time to come.
- What can be done to fix "hot spots" in my house?
- Temperature variations from room to room result when duct work in incorrectly sized. In some cases, our technicians are able to rework the duct system to improve airflow. Another solution may be to replace the windows in a hot room with Low-E glass or have the existing windows tinted. The reduced sun load will cool the room and save energy.
- My air conditioner has just been diagnosed with a bad compressor. Should I repair the system or just get a new air conditioner?
- Compressors fail for a number of reasons. One of the most common is the "burnout." In this situation, acid and burnt varnish are distributed throughout the system contaminating the indoor and outdoor coils and the refrigerant piping. This acidic oil is very difficult and costly to clean-up and will contaminate and shorten the life of the new compressor. In a burnout situation, we recommend replacing the entire air conditioner (indoor, outdoor, and piping) to insure long life and reliability of the new system. If the compressor failure is due to broken valves, lightning strike, etc., compressor replacement a feasible option. A homeowner should then consider the current age of the system, the energy saved by a new high-efficiency A/C, and benefits of a new system warranty.
- What is a SEER rating?
- To understand SEER ratings, we find it helpful to compare air conditioners to cars. The efficiency of a car is measured in MPG or output (miles driven) divided by input (gallons of gas used). The Energy Efficiency Ratio (EER) of an air conditioner is essentially the same measure but with different inputs and outputs.
EER is output (amount of cooling delivered) divided by input (electricity consumed) and is measured in Btu per watt-hour in lab conditions. The Seasonal Energy Efficiency Ratio (SEER) has the same units, but instead of being evaluated at a single operating condition, it represents the expected overall performance for a typical year's weather in a given location. SEER ratings are more useful because they represent real-world conditions.
Just as in miles per gallon, a higher SEER number is better. An 11 SEER air conditioner uses about 10% less electricity than a 10 SEER a/c to do the same job. Today the mandated minimum efficiency of a new air conditioner is 13 SEER. High efficiency models can reach 16-20 SEER, while geothermal heat pumps and ductless mini-splits can reach as high as 20-28 SEER.