Does Your A/C System Need Coolant?

screws and a screw driver

Central air conditioning units are essential for regulating the temperature of the air in homes and offices, and their main job is to keep a constant flow of cool air circulating throughout. The coolant in these air conditioners is supposed to last the lifetime of the air conditioner. However there are several reasons why a unit might need coolant replacement, including accidental damage, wear and tear, or contaminants. Below are a few of the most common reasons why the air conditioning unit may need to be checked out by a professional because it has no coolant.

Check The Thermostat

When a central air conditioning unit doesn’t seem to be cooling, the first step in diagnosing whether the unit needs coolant or not is by checking the thermostat. Sometimes the thermostat simply needs to be reset. It’s a good idea to rule this out before jumping to the conclusion that the coolant needs to be replaced. To do this, you simply need to reset the unit by flipping the breaker on and off in order to reset it. If the unit comes back on and begins to cool, then there is no need for coolant because it was the thermostat hanging. By triggering the electrical components to reset, the air conditioner can begin cooling again.


Sometimes the air being released from an air conditioning unit is still blowing normally but the temperature of the building doesn’t seem to be cooling. This is a good time to check the vents. If you have recently cleaned and reset your thermostat and waited at least thirty minutes with no sign of cool air, stick your hand up to the vents to determine whether or not the unit is blowing air out at room temperature. If the unit has already been reset and is still blowing out warm air then coolant could be the culprit.


The coolant used in air conditioning units is gaseous in form and turns into frost when it escapes through holes or worn spots in hoses. When there is a coolant leak in your air conditioning unit, frost will sometimes collect and build up on various parts of the internal structure, such as hoses, fans, belts, and other components. Frost buildup can be a sign that there is coolant leaking from the machine and that it probably needs to be replaced, along with the damaged components allowing the leakage.

Check For Debris

Sometimes dirt and debris will get inside an air conditioning unit and cause the internal components to stop working. Dirt and debris can clog the fan and other components and keep them from working properly. Before assuming that the coolant needs to be replaced, it is a good idea to open the unit and give everything a thorough inspection and cleaning. Sometimes getting the dirt and debris out of the unit is enough to repair it.

As you can see, there are many possible reasons air conditioners fail to cool properly. In order to determine whether a unit needs coolant, you must rule out other common problems. Hanging thermostats and debris could also be causing the unit to fail. The appearance of frost on hoses and other components indicates a coolant leak. If you’re having any problems with your A/C in San Marcos, Buda, Kyle, New Braunfels, Wimberley, Canyon Lake, or anywhere in Central Texas, be sure to give AirOne Heating and Air Conditioning Repair a call to discuss your HVAC problems and get a no-hassle quote!