AC Pipe Freezing

Summer is finally in full swing which means ridiculously scorching weather. If you are feeling the heat, a broken AC is the last thing on your mind. Have you noticed that your AC has stopped blowing cold air and your AC pipe outside is covered with ice? Unfortunately, ice anywhere outside your AC unit is usually not normal.

1. What causes AC pipes to freeze?

If there is ice buildup on your AC refrigerant lines, you can have either of the following problems:

Blocked airflow over evaporator coils

Your AC is a machine where hot air from the outside comes inside it and this is expelled as cool air in your home. For this operation to happen, airflow should have no obstructions. Converting hot air into cool air is the role of evaporator coils. Evaporator coils contain a large web of refrigerant. The cold refrigerant is flowing inside the coils and this makes warm air that is passing through lose its warmth and humidity producing dry and cool air. Because of this process, this will avoid the refrigerant from freezing. When warm air comes in contact with a cold coil a process called condensation occurs which means that small water droplets will be formed in the evaporator coils. Ideally, these small water droplets collect into the drip pan and eventually pass through the drip line. However, when there is not enough warm air passing through the evaporator coil, the evaporator will quickly ice and this ice will travel along the refrigerant line. Ice builds faster when humid air hits the coils and the process of condensing and freezing continues. Problems that can result in obstructed flow are the following:

Clogged or dirty air filter
Dirty evaporator coil
Blocked or closed vents
Bent or collapsed air ducts
Problems in the blower vents

Low refrigerant levels

Refrigerant is the chemical that runs through the evaporator coil and it is responsible for cooling the air. When the refrigerant levels are low, it causes ice formation. The reason why it has low levels is due to a leak in the refrigerant. When it leaks, the pressure inside the evaporator coil also decreases, and as the pressure drops, so as the temperature of the refrigerant drops. Low temperatures will lead to ice formation. Signs when the refrigerant is leaking:

The AC never seems to shut off or is running much longer than usual
AC is blowing warm air
A sudden increase in the electrical bill

2. What if your AC pipes freeze up?

As stated above, a dirty or clogged air filter can cause your pipes to freeze up. Check your filter first for cleanliness, if it is pretty dirty, changing it alone will not solve your problem, you must remove the frozen ice from your indoor coil first. Step 1: turn off your air conditioner completely Step 2: Turn the fan “auto/on” switch to “on” Step 3: wait at least 4 hours – I know this seems cruel when your house is hot but that is the only way to make sure all the ice is melted from your AC. Step 4: replace the air filter and turn your unit back to its normal setting. If the AC ices up again, you will need professional service such as Heatwave. Bear in mind that if a technician arrives and your system is iced up, he will not be able to correctly diagnose the problem such as a clogged evaporator coil or low system charge if the unit is iced up when he gets there. To avoid having the technician making a second trip or worse, waiting for the ice to melt, call us for service, follow steps 1 to 3 above, and schedule the technician to come over 4 hours after you call.

Looking for AC Repair Near Tucson, AZ?

If you’re experiencing trouble with your air conditioner our licensed and insured HVAC team will be more than happy to inspect your cooling unit and perform ac repair, or if needed immediately, emergency air conditioning repair. We’ll take the heat so you can stay cool!

Heatwave Air Conditioning and Heating

(520) 623-1855

3131 E 45th St, Tucson, AZ 85713

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