Signs That Your Central AC Unit Requires More Refrigerant

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Up until a few years ago, I would get sick whenever the seasons would change. I couldn't figure it out, until one day when an HVAC contractor pointed out my filthy air filters. I am embarrassed to say it, but I didn't know that air filters had to be changed at all, and all of that filthy air was circulating through my home. After I changed the air filters and started to take care of my HVAC system, my allergies got a lot better and I didn't feel as sick. I want other people to understand the massive benefits of taking care of their HVAC systems, so I put up this website.


Signs That Your Central AC Unit Requires More Refrigerant

22 March 2017
 Categories: , Articles

If your central AC system is not working as well as it should, then you may be worried that it is time to invest in a new system. However, the system is likely to last at least 15 years. If the cooling system is much newer than this, then there is a chance that the unit has a low amount of coolant. This is one of the common reasons why a central AC system may not work as great as it should. If there is not enough coolant, you will see some telltale signs of this. Keep reading to find out what they are. 

The Unit Is Blowing Warm Air

One of the most obvious signs that the central AC system is low on coolant is when it appears to be blowing warm air out of the vents. Simply put, the unit needs a constant amount of coolant to produce cool air. This coolant runs through a compressor unit that forces the fluid into a gas. The gas moves through an evaporation coil in the house-side part of the unit. The coolant pulls out the heat from the air moving past it, and the newly cooled air blows up into your house. 

When there is not enough coolant forced through the compressor and into the evaporator coil, then very little heat can be pulled out of the air. The air then remains lukewarm when it moves into your house. However, the AC unit will continue to run and function as it normally would and cycle on and off. This means that a great deal of electricity is wasted, even though the unit is not cooling much. 

If you notice the unit running constantly and failing to blow cool air into your house, then there is also a chance that the outside vents are clogged with debris. Check for this issue first before contacting an AC repair specialist. 

You Hear A Hissing Sound

If you hear a hissing sound like air is being released from a tire, then this is a sign that the AC unit has likely sprung a leak in one of the coolant lines. To make sure that the noise is not an electrical one or the result of the compression pump gearing up to work, turn off the AC unit and listen closely. You should continue to hear the sound when the unit is off. 

You will hear hissing from the AC unit because the coolant is placed under a great deal of pressure. The amount of pressure will depend on the type of coolant that is held in the appliance. If you have an older one, then the hissing may be more subtle, because the Freon will not be under as much pressure as a newer one with R-134 coolant.

If you have a newer unit that holds R-134 then the device will come with a few different types of pressure gauges. These gauges can be located in the control panel. A low pressure gauge will be seen, and the pressure should sit between about 25 and 55 PSI depending on the ambient temperature of the unit. The high one should be between 135 and 345 PSI. If both of these PSI readings are low, then this means that pressure has been compromised on both the high and low pressure ends of the unit. Refrigerant will need to be added.

While newer AC units contain refrigerants that are not harmful to the environment, the system should be inspected for a leak. Leaks will typically become larger over time, and a patch should be secured as soon as possible before the unit fails completely. This can happen if very little refrigerant runs through the compressor, but the pump still runs. 

For more information, contact an air conditioning repair specialist at a company like Classic Air and Heating.