Why is my AC copper line not cold?

Author: Dr. Cindy Tromp  |  Last update: Saturday, May 3, 2025

The Copper Pipe (Suction Line) should be sweating and cold to the touch during a hot day. If it is not cold, your compressor could be off (bad capacitor/ hard start kit) or low on Refrigerant. Your Breaker is Tripped. Be Careful because this usually indicates a problem with the compressor or wiring.

Should my AC copper line be cold?

The large copper tubing with the insulation should be cold, while the smaller diameter copper tubing should be warm. When the thermostat calls for cooling, is the outside unit running? The condenser fan on top of the unit should be blowing warm air out the top, and the compressor should be running.

Why is my AC line not getting cold?

If your AC is running but not cooling, it could be due to a dirty air filter, incorrect thermostat settings, a malfunctioning thermostat, a refrigerant leak, dirty condenser coils, blocked vents or ducts, a faulty compressor, frozen evaporator coils, or electrical issues.

Why are my AC copper lines hot?

The liquid line going to the house being hot is a sign of either a dirty outdoor unit coil or the outdoor fan not turning. Turn off the breaker to the unit and wash the coil with a garden hose. You may see black water running from the bottom of the coil when you first do it, a sign of a plugged coil.

Why is my AC suction line not cooling?

Problems with Suction Lines

If AC suction lines are clogged, improperly sized, bent, or kinked, the flow of vapor will be affected. If the line is compromised, the compressor will not receive an adequate amount of refrigerant, which can affect the entire system.

Don't Check Refrigerant in Mini Splits. Here's Why!

Should the suction line be cold?

Overall, you'll want your temperature to be below 65 degrees at the compressor inlet. If you see a lower temperature, then you'll want to start looking at airflow.

Why is my AC running but not getting cooler?

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.

Why is my AC pipe not getting cold?

The Copper Pipe (Suction Line) should be sweating and cold to the touch during a hot day. If it is not cold, your compressor could be off (bad capacitor/ hard start kit) or low on Refrigerant. Your Breaker is Tripped. Be Careful because this usually indicates a problem with the compressor or wiring.

How long do copper AC lines last?

Refrigerant lines typically last 20-25 years. Any damage or contamination can shorten the lifespan of your lines, but typically that's how long they should last. To ensure that you get the full life expectancy out of your lines, make sure you get a high-quality install from a trusted technician.

Should AC copper line be insulated?

Refrigerant lines and pipes should have insulation around them to protect them from damage and inefficiency. Winter erosion, UV damage and condensation may require insulation replacement to avoid temperature fluctuations or malfunctioning.

Should I turn off my AC if it is not cooling?

Turning off your AC when it's not cooling is more than a precaution; it's a necessary first step in troubleshooting and protecting your system from further damage. By understanding when to perform simple checks and when to call in the experts, you ensure your air conditioner remains a reliable refuge from the heat.

How do I know if my AC line is bad?

AC is Producing Warm Air

One of the surefire signs of a clogged refrigerant line is if you notice the AC producing warm air when you expect cold air. The warm air is caused by a problem with the proper circulation of the refrigerant fluid, which is instrumental in cooling the air.

Why is my AC not blowing as cold as it should?

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.

Does length of AC copper pipe affect cooling?

The air-conditioning copper pipe is mainly connected to the indoor unit and the outdoor unit. The refrigerant flowing inside is the refrigerant (Freon). If the copper pipe line is too long, the refrigerant will flow at a slower speed, resulting in no refrigerant in the air-conditioning compressor.

How cold should my AC line be?

For efficient cooling and to prevent overworking your AC, the temperature of the air coming from your AC vents should ideally be 14-20°F cooler than the air entering the system.

Why is my car AC full of freon but not cooling?

The compressor plays a vital role in the A/C system, as it pressurizes and circulates the refrigerant. A compressor that is not functioning correctly can cause warm air to blow from the vents. Common issues that can affect the compressor include a faulty clutch, electrical problems, or mechanical failure.

Why is the copper line on my AC hot?

The pipe running to the interior AC unit should be cool to the touch, not hot. A hot pipe indicates that there is a problem with the compressor, which sends cooling refrigerant through the system, or that there is a blockage in the line.

When should I replace my AC copper pipe?

You may additionally need to replace your copper cooling agent line in case of leaking. A sign of a refrigerant line leakage is an oil discolor as it moves in the cooling system along with the refrigerant. It continues to be noticeable after the refrigerant has steamed off.

Why is my AC running but not cooling?

This can occur when there are blockages or restrictions in the air ducts, preventing the cool air from reaching your home. Common causes of airflow problems include dirty air filters, blocked vents, and debris in the air ducts.

How do you tell if your AC pipe is clogged?

A clogged AC drain line symptoms include:
  1. Musty, moldy smell near your indoor unit or in air from the registers/vents.
  2. Standing water near the indoor unit.
  3. Water damage in areas near the indoor unit.
  4. AC system is not cooling your home.
  5. AC system shuts down or doesn't turn on.

How do I get my AC cold again?

Why Is My AC Not Blowing Cold Air? Easy Fix
  1. Introduction. ...
  2. Check the AC unit to make sure it's not running on low refrigerant. ...
  3. Look for debris in the condenser, which is part of the system that pushes air through the vents. ...
  4. If you have a coil unit, check your airflow. ...
  5. Check your filters and replace them if necessary.

How do I reset my central AC not blowing cold air?

Use these tips to reset an air conditioner using the reset button:
  1. Turn your thermostat to the “off” setting.
  2. Turn off the circuit breaker that powers your AC.
  3. Press and hold the reset button for three to five seconds.
  4. Restore power to your AC by flicking the circuit breaker back on.

Why is my AC not cooling below 75?

Your AC might be stuck at 75 due to various reasons like clogged filters, refrigerant leaks, or the wrong unit size. It's best to have a professional diagnose and fix the issue.

How to unclog an AC drain line?

How to Unclog Your AC Drain Lines in 9 Steps
  1. Turn Off Your Air Conditioner. ...
  2. Locate the Drain Line Pipe. ...
  3. Remove the Cap From the Pipe. ...
  4. Inspect the Drain Line Pipe. ...
  5. Unclog the Drain Line Pipe. ...
  6. Pour in Vinegar. ...
  7. Use a Wet/Dry Vacuum Cleaner. ...
  8. Reconnect the Cap to the Drain Line Pipe.

Previous article
Why did they stop making purple glass?
Next article
Can you add floetrol to cabinet paint?