Most commonly asked air conditioning questions

There’s nothing like walking into a cool home or business on a hot summer’s day! Cooling systems, such as air conditioners, make that comfort possible. Many homeowners aren’t particularly familiar with these systems, so the pros at HVAC.com are here to answer your most common AC & air conditioning questions!

Air conditioning questions: how does my AC work?

Air conditioners work to cool a home using refrigerant that absorbs and discharges heat. Here are the steps an AC takes to cool your home.

• Warm air from your home moves across the air conditioner’s evaporator coils. The refrigerant within the coils absorbs the air’s heat. Refrigerant converts from cool liquid to hot vapor, cooling the air.
• The vapor travels to the compressor located in the outdoor air conditioner unit. The refrigerant vapor is compressed here, raising temperature and pressure.
• Refrigerant travels to the condenser where it is condensed into a liquid form again. This causes heat to release, and heat dissipates to the outdoors through the exterior unit’s fins.
• The refrigerant is now cooled and in a liquid state. It cycles back to the indoor unit, regulated by the expansion device, so the cooling process can continue.

AC questions: what are the different types of air conditioners?

When most people think of air conditioners, systems with a condenser outdoors and an air handler indoors are what they visualize. In reality, there are many different types of air conditioners that can be used to cool a home.

• Central air conditioners utilize an outdoor condenser and an indoor air hander (that also works with the furnace or heat pump) to deliver cool air indoors.
• Heat pumps can operate for both heating and cooling, and are an option for central air conditioning.
• Ductless mini-split air conditioners utilize individual air handlers installed throughout the home, connected to an outdoor heat pump, to provide zoned cooling in the specific areas that need it.
• Portable and window air conditioners are additional options for space cooling – they are not a whole-home cooling solution.

Air conditioning questions: common AC repairs

Air conditioners are complicated mechanical systems with many working parts. Good maintenance will help prevent AC problems, but a system may still malfunction over the course of a cooling season. Below are some common AC repair issues and their fixes:

• Refrigerant leaks. The lines transporting refrigerant through the system can leak, causing refrigerant to spill out and less pressure to complete the cooling process. To solve the issue, your air conditioner repair technician will diagnose the source of the leak and fix it to prevent further issues. Your AC system will be recharged so the appropriate amount of refrigerant is added to the system.
• Drainage problems. The cooling process produces condensation that needs to exit the system. Your air conditioner is equipped with a condensate drain line and drip plan to handle the flow of moisture. If these components become clogged with algae or obstructions, or are damaged, moisture can back up into the system, causing humidity problems within your home and damage to your air conditioner. Your technician will clear the clog or repair components so moisture properly exits your air conditioning system.
• Frozen condenser coils. The air conditioner’s condenser coils can freeze up, preventing your system from cooling. This typically happens when there is poor airflow through the unit, caused by obstructions such as dirty filters or debris surrounding the outdoor unit. Low refrigerant levels may also be the cause. Your technician will diagnose the cause and correct it, deicing your coils so the cooling process can flow smoothly again.

AC questions: measuring air conditioner efficiency

An air conditioner’s efficiency is measured in SEER. SEER stands for Seasonal Energy Efficiency Ratio. A unit’s SEER is calculated by dividing the unit’s cooling output over an average cooling season by the amount of electric energy input over the same period.

The higher the SEER rating, the more efficient the air conditioner. The minimum SEER allowed by law for newly manufactured air conditioner is 13 or 14, depending on where in the country you live. The most efficient air conditioners on the market have SEER ratings of around 22.

Find local help for AC repair

HVAC.com is home to a comprehensive Contractor Directory that connects you to local HVAC contractors who can answer all the AC questions specific to your home. Enter your ZIP code to find professionals in your area who can come take a look at your cooling system and give answers to the air conditioning questions that are standing in the way of your home comfort.