HVAC Questions & Answers
How Do Air Conditioners Work?
The process of cooling your home starts at the thermostat. When you adjust the thermostat to either heating or cooling mode an electrical pathway is formed and goes to the circuit board in the furnace. From there it is transmitted to your condenser, for cooling, or your gas valve, for heating. The air begins to circulate throughout your home using the ductwork in your attic by using a “blower motor” located inside of your furnace. In cooling mode your condenser, the outside unit, comes on and begins to pump refrigerant through copper lines into your evaporator coil. The warm air passes across the evaporator coil, which has become cold, and gives up its heat and moisture. Once it has passed the coil the “conditioned” air is then distributed throughout your home. With so many different moving parts and processes that include electrical, refrigeration, and even a little plumbing it may seem overwhelming that you could fix anything on your own.
Why is my air conditioner blowing warm air?
Your air conditioning system may have started blowing warm air for the following reasons:
- Your thermostat setting was accidentally adjusted to "Heat"
- Your thermostat is set to "Off" and your fan is set to "On" instead of "Auto"
- Your condensing unit (the a/c unit outside of your house) is not running.
What is High Efficiency?
Energy Star guidelines for air conditioning and heating systems dictate a minimum of 14 SEER to be considered high efficiency. Visit our What is High Efficiency page to learn more about High Efficiency Air Conditioning and Heating Systems.
What is SEER?
S.E.E.R. stands for Season Energy Efficiency Ratio. Visit our What is High Efficiency page to learn more about SEER ratings and what they mean to you.
What is EER?
E.E.R. stands for Energy Efficiency Ratio. Visit our What is High Efficiency page to learn more about how EER ratings are established and how it can affect your electric bill.
What is Indoor Air Quality (IAQ)?
How often should I change my filters?
There are many different types of filters out in the market today. Some of these filters claim that you only need to change them once every three months, others six months, some even say that you never have to change the filter. The truth is that if you have a filter in your home that is located in the return air vent, this is the largest of the vents and usually has tabs for where you can open the grille and replace the filter yourself, then this filter should be replaced once a month. The reason that you should not wait any longer than this is because over time the filter will catch the dirt, bacteria, dust, and other indoor air pollution particles that circulate throughout your home and become an obstruction to airflow. When this occurs your system will begin malfunctioning and may result in costly repairs and lasting damage that requires evaporator coil cleaning. If you would like more information about airflow or believe that you may have waited too long and need a coil cleaning contact us today to schedule your service call.
Why does my a/c unit constantly run and never reach my thermostat setting?
There are several different possible explanations for why your air conditioning system continues to run and never reaches the thermostat setting.
- Your thermostat is set to a temperature that is more than 20 degrees less than the temperature outside. Meaning that if the outside temperature is 95 degrees and you have your thermostat set to 70 degrees the manufacture only guarantees a 20 degree difference. So the manufacture only guarantees that your home reach 75 degrees.
- The filter inside your home has restricted the airflow and is not moving enough air across your evaporator coil to remove as much heat as the house is generating. This can easily be fixed by checking your filter once a month and replacing it.
- Your air conditioner is low on refrigerant. If your air conditioning system is blowing cool air, but not cold air you may be low on refrigerant or your system was never charged correctly to begin with. If you are low on refrigerant you may have a leak in your air conditioning system that requires repairs.
Do It Yourself A/C Repair
Listed below are several of the more common issues that you can resolve on your own with a little bit of training. Save yourself a service call and feel like a pro when you do your own a/c repairs!
Most homeowners have their air conditioning system located in their attic and if you have been in your attic recently you may have noticed that there is an extra light switch. This light switch may be on the wall inside your home near your attic access ladder or it could be located in your attic near the switch that controls the light in your attic. This “light switch” is not actually a light switch. It is a safety switch that controls power to your furnace. If someone accidentally leaves this light switch off your thermostat may lose power and turn off or your air conditioning system will not turn on. The power that goes into your furnace powers your circuit board which operates your air conditioning system and power your thermostat and condenser. It is very common for homeowner, electricians, cable repair companies, and even roofers to sometimes flick this power switch on and off believing it to be the light switch. Without meaning to this switch is then left in the off position and your air conditioner will no longer operate. There are some things that you can do to help prevent this issue:
- Label the light switches “Light” in black marker and “Heater” in red marker to ensure that there is no confusion.
- On your next maintenance appointment ask your HVAC contractor to place electrical tap or some kind of warning on the light switch that operates the furnace
- Make sure to check this light switch before calling your HVAC contractor to save yourself a service call!
A/C Drain Lines
When you are cooling your home your air conditioning system is producing water. This water is made by the warm air that is circulating into your attic and when it passes your evaporator coil, which is cold, condensation occurs. The water that is left on the evaporator coil slides down the aluminum fins and collects into a drain pan. This drain pan is connected to a PVC pipe that is run into a main drain line. From time to time your air conditioning system will produce a large amount of water followed by only a small amount of water. Over time rust, dust, dirt, and algae will build up in your PVC drain line in your attic. Left untreated this Algae will then build up and block the water. The water will then start to back up and will overflow to the lowest point of the drain pan. Most air conditioning systems have an emergency overflow pan underneath of your evaporator coil just in case this happens. This will prevent any water damage to your sheetrock. If this problem is not resolved the emergency drain line will eventually overflow and you will be faced with hundreds of dollars in sheetrock repair. There are a few things that you can do to help prevent clogs.
- Check outside your home and locate where the emergency drain line drips to, if you are having trouble locating this drain line ask your HVAC contractor to point it out for you on your next maintenance check-up.
- Ask your HVAC contractor if they treat your drain line during maintenance.
- Ask your HVAC contractor if there is an area that you can treat the drain line by pouring bleach into the line.