Imagine it's mid-July. You're inside, but it's feeling a bit warm.
You go to the thermostat and lower the temperature, only to discover…
The air coming out of your vents isn't cold. It's hot!
You wonder, "Why is my AC blowing hot air?"
More importantly, you want to know how to fix this problem and cool your house down.
Is the air really… hot?
For most people who have this problem, the air isn't truly hot. It just feels that way because you're expecting it to be cold. In reality, it's more or less the same temperature as the ambient environment.
Regardless, the air definitely seems hot. And that's not what you want.
When your AC is running, the air you feel from the vents definitely should be cold. If it doesn't, there's something wrong.
Let's look at some things that can cause this problem.
Reasons your AC might be blowing hot air
While there are any number of reasons your air conditioner might be blowing less-than-cold air from the vents, these are the most common ones:
1. The fan is on, but the AC isn't.
This is the best case scenario. It means somebody bumped the fan switch on your thermostat to the "on" position.
To correct this, move the switch to the "auto" position and be sure your thermostat is set to "cool."
After that, feel the air that comes out of the vents. It'll probably be nice and cold.
2. You've got a dirty air filter.
Dirty air filters block airflow and prevent your AC from cooling properly.
When the filter is so dirty that air can't move through it, the air conditioning system is starved for air. This over works the fan and the blower motor. Also, it makes it so the AC coil can't do it's job.
You might feel hot or warm-ish air coming out of the vents.
3. The outdoor coil is really dirty.
Just as having a dirty filter prevents the system from cooling properly, a dirty outdoor coil prevents the AC from moving heat away from your home.
When the coil hasn't been cleaned in a long time, your AC won't work properly. It will still blow air, but the air won't be cold.
4. Your system is leaking refrigerant.
Refrigerant is essential for heat transfer within an air conditioning system. If enough of it leaks out, the AC won't be able to remove heat from your home.
And it won't blow cold air until you fix the problem.
Refrigerant leaks are a real pain. Depending on the location of the leak, the age of your AC, and how fast it's leaking out, there may be different solutions available to you.
Speaking of solutions…
Solutions for an AC that blows hot
Let's start with refrigerant leaks. If your AC is blowing hot and an HVAC technician confirms the presence of a leak, here's how to proceed:
- Do you have an older system that uses R-22 or R-410A refrigerant? If your AC uses R-22, it's best to replace the air conditioner. R-22 is an obsolete product, and very few HVAC companies keep it around these days. Even if you find one that does, it will be expensive to keep topping it off. R-410A refrigerant is a different story (and a better one, usually). Depending on the extent of the leak in an R-410A system, an HVAC technician might suggest adding refrigerant to the unit.
- Is your air conditioner still under warranty? If it is and the leak is somewhere on the evaporator coil (the most common place for a leak, in our experience), then the best option is to replace the coil. You'll only have to pay for labor.
- Is it a slow leak on an out-of-warranty system? As long as the system doesn't use obsolete R-22 refrigerant, it's usually possible to top it off with more refrigerant periodically. That said, this isn't a good long term solution because you're not fixing the leak! You're kind of kicking the can down the road. Replacing the system is the only long-term solution.
The other problems we mentioned, dirty air filters and a dirty outdoor coil, are easily preventable!
To prevent a dirty air filter from interfering with your AC's ability to cool, either replace the filter or clean it per the manufacturer's instructions.
Most disposable air filters are 90-day filters, although you may want to change it more frequently during the summer. If you've got an air filter you can clean, it's a good idea to keep two of them on hand so that you're still filtering air while cleaning and drying the other filter.
PV Priority Plan members enjoy regular air filter swaps during our bi-annual preventative maintenance visits! That's in addition to comprehensive service that ensures your AC delivers peak performance all season long.
As for the dirty outdoor coil, it's essential to clean it at least once per season. We do this during AC tune-ups and during our regular preventative maintenance visits for PV Priority Plan members.
Conclusion: Regular maintenance helps prevent your AC from blowing hot
While there are other problems that could inhibit your air conditioner from blowing cold air, the most common ones are refrigerant leaks, a dirty coil, or a dirty air filter.
If you're worried about an air conditioner that isn't cooling your home properly, PV Heating, Cooling & Plumbing can help!
We serve all of Metro Atlanta and can determine exactly what's going on with your AC, so you can pursue the best possible long-term solution.
Give us a call today at (404) 798-9672 or schedule service online!
