Check the Refrigerant Level If the level is low, it may indicate a leak in the system that needs to be repaired. The technician can also check for any blockages in the lines that can restrict the flow. If any blockages are found, they will need to flush the system or make adjustments.
Make sure it has power (check outlet if a window unit, check circuit breaker if hardwired). Check thermostat battery if accessible (some wall units use a battery). Check if filters are clogged. Check outside duct for obstructions.
If you are having issues with your AC not working, checking your thermostat is the first place to start. Begin by ensuring that your thermostat is set to either the “cool”, “automatic”, or “air conditioning mode” setting (instead of “heat”). Set the temperature to a low degree to initiate the air conditioner.
The first step you should take when troubleshooting your air conditioning unit is ensuring that your thermostat setting is on cool rather than heat. Yes, this may sound like a no-brainer, but people forget to change this setting after the winter months more often than you would think.
Frozen Coil
This is one of the most common air conditioner problems. There are many reasons that could cause a frozen coil. The reasons could range from low refrigerant levels to mechanical failures.
The first thing you should do to test your HVAC system is to test the thermostat. This is the easiest way to tell if your system is working properly. All you need to do is compare the readout on your thermostat with the readout on a thermometer that is not connected to your HVAC system.
One of the biggest reasons people experience air conditioner problems is due to a dirty furnace filter. This is very common and easily prevented. A dirty filter restricts the amount of air that flows through the evaporator coil. When this occurs the coil gets too cold and the system will freeze up.
There are a number of reasons why your air conditioner might be running but not cooling. It could be an issue with the thermostat, the compressor, or the evaporator coils. Or, it could simply be clogged with dust and debris, which is preventing it from working properly.
Check for the simplest remedies first, such as whether the power cable is still connected and the switches are all in the right position. You may also need to check and replace fuses, reset breakers, check the pressure switch, and activate a reset switch to get the machine back into power mode.
Thermostat Issue
If you notice your air conditioner is not turning on when you need it to, take a moment to check your thermostat. Your thermostat not only sets your indoor temperature, but it also tells the AC units when to turn on and blow cold air. Make sure that the thermostat is on and that the screen is lit.
Check the Airflow
First, make sure all your vents are open and nothing's blocking them. Sometimes, people will close off vents to rooms that are getting too much air or to rooms that don't get much use, but that too is hard on your HVAC system.
Making a diagnosis involves multiple steps including taking a medical history, performing a physical exam, obtaining diagnostic tests, and then examining the data to come to the best explanation for the illness. Taking a medical history is the first step in making a diagnosis.
The first thing you should check for when troubleshooting a pneumatic system is the airflow or pressure issues within the system. Expect the air in a pneumatic system to flow in a steady and controlled manner, usually referred to as laminar flow.
The first thing you'll want to do is check the thermostat. If you have air that's controlled by a thermostat, make sure a faulty thermostat isn't what's causing the problem. In some cases, the batteries may have died or the unit is malfunctioning. Reset the thermostat to see if that turns the AC unit back on.
How To Check an AC Unit. To test your central air conditioning system, turn the AC unit on, place a thermometer on the supply register for five minutes, then check the temperature and compare it to the temperature from the return vent.
#1 Most Common Air Conditioning Repair – Bad Capacitor
The fan of course makes a whirring noise, the compressor is like a deep buzz like a refrigerator running. Holding your hand above the fan should feel warmer than the outside air.
For AC capacitor replacement, anticipate spending between $150 and $400, depending on the capacitor's type and accessibility. A bad AC capacitor is a fairly minor repair, and most HVAC technicians will recommend a repair rather than replacing the unit when the capacitor is the problem.