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Introduction
Are you struggling to find out what’s wrong with your AC? Has your liquid line started getting cold out of nowhere?
Well, that might make you think relentlessly about why my liquid line is cold?
The most frequent reason behind your liquid line being frozen is restricted airflow. Your liquid line will stop working when pollutants block your filter drier. Other common reasons include a stuck solenoid valve and TXV being partially closed. Moreover, a low level of refrigerant can cause this issue too.
Well, those were the reasons that might disturb your liquid line. But no worries! I’ve mentioned all the tips and tricks on how to fix these issues.
Let’s get going then!
4 Reasons Why Your Liquid Line is Cold and Their Solution!
Often we mistake the liquid line restriction with undercharging of refrigerant. For this when ac works during the day but not at night it might be a liquid line problem. But it’s more of a refrigerant charge problem. Here are the reasons why your liquid line is cold
Reason 1 of 4: Insufficient Airflow
The main function of the evaporator coil is to take in heat from the air. But the condensation on the coils can get frozen when there is no heat (as in air) to take in.
A lot of problems can lead to poor airflow. For example, a dysfunctional blower fan can block air filters or this can happen due to faulty ductwork. Or simply the air filter is clogged with dust.
Source: Home Stratosphere
To maintain the coils functioning properly air conditioners require a good amount of airflow. The temperature drops when air cannot pass flexibly through the evaporator coil. As a result, the liquid line gets cold.
Solution
First, you have to warm up the evaporator coil. You have to turn off the ac and let the coils return to their normal state. The coils can take from 12 up to 24 hours based on their condition.
Alternatively, you can switch to a fan-only mode. This will reduce the time duration of your whole process. Even in the absence of a refrigerant cycle, it will let warm air spread on the coils.
You will require the necessary materials to hold the water if there is a large amount of ice. Or it can harm the other parts of your Air Conditioner.
Reason 2 of 4: Filter Drier is Jammed Up
The average lifespan of a liquid line filter drier is limited. It’ll ultimately clutter up from all the contaminants it screens out of the refrigerant.
Source: qualitycomfortfl.com
The moisture sieve beads, however, will finally achieve concentration. They can only retain this much water. It can also make a noise like the one it makes during a power outage.
A blocked air filter can also be the reason behind insufficient airflow. Lack of airflow stops the evaporator coils from taking in the essential amount of heat. As a result, the functions are interrupted.
The coils can also get obstructed by the dirt spread by clogged air filters.
Solution
Replacement is the only option for a clogged filter drier. They’re cheap, and a skilled air conditioning repair service can do them efficiently. Or you can do them by yourself as well. But before that, you need to get yourself some good filter dries to attach to your AC.
And guess what? I have the best filter drier list here after I’ve talked to my own HVAC mechanic.
Products | Compatible Refrigerants | Price |
PowerWell Refrigerant Filter Drier | HFC , CFC , HCFC | Order Now |
Appli Parts Refrigerant AC filter drier | r1234yf, r134a, r290, r22, r407c, r404a, r507a, r600 | Order Now |
Now you have the best filter drier, you should be able to change your AC’s filter drier. Check out this tutorial and follow it properly to change the filter drier perfectly.
Also, you might want to know what is causing the clogs in the filter drier?
Generally, they can last for a long period of time. To determine how pollutants are entering your refrigerant line, thoroughly inspect your whole refrigerant circuit. Including the evaporator and condenser coils.
To avoid the new filter-drier from becoming blocked, you need to look out for holes in the circuit. They must be filled and weak connectors and must be secured.
Also, remember to clean your air filter regularly. It’s also recommended that you change your air filter every 3 months. If you are planning to replace your AC’s air filters then check out these two filters.
- Simply by MervFilters, has a plethora of options in size so you can choose the one that fits your AC.
- Filtrete AC Furnace Air Filter with 300 MPR rating which is equivalent to Merv 5.
Reason 3 of 4: Low Level of Refrigerant
A sufficient amount of refrigerant is required for conditioners to operate properly. AC units are designed to operate in a loop system. It means that refrigerants will not get lost out of anywhere.
Therefore, low refrigerant means a leak or absence of charge causes the issue. When there is a refrigerant leak, the pressure of the refrigerant suffers a downfall.
You can use a refrigerant leak detector to check this issue. I would recommend using Elitech WJL-6000S Freon Leak Detector. That’s because I have one of these and it never disappointed me.
You can also choose the Aprvtio Refrigerant Leak Detector with LED Light.
But at the same time, the amount of expansion required remains intact. It lowers the coil temperature by creating an overall cooler temperature.
The evaporator coils start freezing which eventually leads to the liquid line getting cold.
Solution
Your air conditioner’s refrigerant is under a lot of pressure. When you have a leak in your refrigerant line, you can usually hear refrigerant escaping as the pressure is released.
Listen for hissing or gurgling near the outdoor unit while the air conditioner is off. There can be no other cause for these sounds. So if you hear them, you should see a specialist.
You can choose any duct tape between ul 723 and ul 181 to fix the leaks.
Reason 4 of 4: When the TXV Gets Stuck
A TXV (thermostatic expansion valve) can become trapped when the valve gets overheated. Oxidation can react with the rust inhibitors in the system’s initial oil charge. And that can also cause TXV to get stuck.
Loss of refrigerant from the powerhead, cap tubing, and bulb assembly is the most typical cause. For that TXV gets stuck and this leads to the liquid line getting cold.
These are all the reasons mentioned above that might cause your liquid line to get cold.
Solution
You can free up the TXV when it becomes stuck. But the question is how to free up TXV when it is stuck?
Start by adding a lubricant additive such as A/C ReNew to free stuck TVX. Even after the additive is inserted, after a few hot and cold water sessions, you’ll see improvement. But it may require up to 48 hours of standard air run time
The TXV must still be engaged by dipping the bulb in hot and cold water numerous times.
Before applying any chemicals to the refrigeration cycle, consult with the manufacturer. Ensure that the guarantee will not be canceled.
FAQs
What causes the liquid line to stop in the first place?
Insufficient Airflow can cause your liquid line to stop working. Even in the summer season, this can result in your liquid line freezing. Coolant will not receive sufficient heating to be discharged indoors due to poor ventilation. And this will lead to a frozen line.
How can I understand if my air conditioning duct is frozen?
Aside from visible frost on any area of your HVAC machine, an absence of chilly air is an indicator of a frozen AC unit. If you place your palm in front of your supply vents and you feel hot air flowing out. You most likely have frost in the system.
How long does an AC coil last?
An evaporator coil if properly maintained will generally last from 8 to 14 years. This is the average shelf life of an evaporator coil. It is quite similar to the life expectancy of an AC. Your coils will have a shorter life if your unit isn’t carefully maintained.
Final Thoughts
That was all our take on why my liquid line of AC is cold. We hope that you have found your answer to why your liquid line is not working.
A special tip for you would be to always check for your filter dryers. Try to keep them clean and maintain them regularly.
Good luck!

HVAC tech with over 30 years of experience. Retired and doing repair work on the side around Madison County, AL.