Air conditioners need the proper amount of airflow and refrigerant to keep the cold coil from freezing over. While this sounds counterintuitive, running low on refrigerant can cause the indoor coil to produce ice because the system does not have enough pressure to keep the temperature of the coil above freezing.
Low freon can cause your coil to freeze and that would stop your cooling, aside from mechanical reasons low freon can cause.
The lines freeze when the cold air isn't being moved properly. This can be due to a few things, but the most common is low refrigerant. Dirty air filters, dirty coils, blocked or closed registers, blocked or closed returns can all contribute to low air flow, too, as can broken fan motors.
If freon levels are really low the motor gets insufficient oil and wear will increase dramatically. The compressor will overheat and die quickly.
The problem with running a standard AC at such low temps is that once the evaporator is below 32F it'll begin to form ice and there is no mechanism in place to allow a defrost. Refrigerators are all outfitted with defrost timers and they will periodically shut down the compressor and melt any ice that formed.
If you set the thermostat too low, it strains the AC. This leads to air conditioning malfunctions and costly repairs.
1st Step: Turn Your HVAC Unit Off.
Even if it's sweltering outside, you still need to turn OFF your air conditioner! Running a frozen air conditioner will wear out parts much faster, and could overheat your unit. Worn parts are bad news for the most expensive piece of your HVAC unit—the compressor.
While the refrigerant in your vehicle can escape even without a leak, it's often not enough to cause significant issues unless you've failed to top up the refrigerant for years. When the lack of refrigerant becomes significant though, it can cause a number of problems, including an overheating driver in the summer sun.
If you want the quick and easy answer, you should never run your air conditioner when it's low on refrigerant.
In most cases, frozen AC lines result from a malfunctioning evaporator coil. This element plays a key role in the heating and cooling process — and if it's not working, temperatures won't adjust properly. Not only can poor airflow damage the AC, but it's also uncomfortable (especially during summer).
Hissing or Bubbling Noise
If you hear a hissing or bubbling noise from your air conditioner, it could be a sign that your system is low on refrigerant. A hissing noise indicates that the refrigerant is not circulating through the system as it should.
A common rule of thumb is that most models can function properly only above 68 degrees Fahrenheit. Any lower temperature will result in the system freezing up. In addition to a frosty refrigerant, the piping and coils could also become covered with ice.
Strain on the Compressor
When the Freon level is low, the ac compressor works harder to maintain the cooling process. This increased workload can lead to compressor overheating and potential damage, resulting in expensive repairs or even the need to replace the compressor entirely.
Most systems need Freon replacement anywhere from once every two to five years from a professional HVAC Contractor. The most significant exception to this rule is when there is a leak in the air conditioning system, which decreases the amount of refrigerant in an AC unit over time.
An AC leak will lead to warmer air from your vents over time. In most cases this can be fixed with a proven stop leak additive to seal up any leaks. When it's time for an AC recharge, turn to AutoZone.
First, check your filters and coils for dirt and debris that may be impeding airflow. Once you've cleaned the filters and coils, run the air conditioner with just the fan so that the ice accumulation can melt off. If the AC still doesn't blow cold air, it could be that refrigerant levels are too low.
Two primary factors can lead to the formation of ice on your AC pipes: restricted airflow and low refrigerant levels. Restricted airflow prevents warm air from passing over the evaporator coil efficiently, which is crucial for absorbing heat from your home.
Well, the thawing process could take up to 24 hours depending on the size of your unit, the extent of the ice buildup, and the efficiency of your blower fan. If the freezing on your air conditioner was just starting, it could clear up faster in an hour or two.
When you notice that your air conditioner isn't cooling, your first action should be to turn it off. This might seem counterintuitive—after all, you want your home to be cool. However, continuing to run an AC that isn't effectively cooling can cause further damage to the system.