The problem may arise as a result of dirty air filters, a malfunctioning fan or a refrigerant leak. In order to fix this, you'll need to call the experts. If there are leaky coils, your HVAC technician can replace them.
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.
Your AC unit isn't producing cool air as well as it used to because dirty coils may be hindering its ability to remove heat in your home's air. It could also not work properly due to a clogged filter and refrigerant running low, which are also the most common causes why you feel warmer these days.
One possible reason your AC is not reaching the set temperature is that the thermostat could be dirty. If dirt, dust, or other debris has accumulated within the thermostat box, it can cause the wires to heat up or other issues. Thermostats are cleaned during routine HVAC maintenance to help prevent this from happening.
Another possible reason could be a dirty condenser coil. Located outside, the condenser coil dissipates heat from the refrigerant, not the cooled air. Dirt, leaves, or debris can block the coil, reducing its ability to transfer heat and thus making the AC work harder.
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.
Your AC might not cool properly due to thermostat issues, an undersized unit, or extremely high outdoor temps—so check those first. Keep an eye on airflow—replace clogged filters every 3 months, and make sure vents and ducts aren't blocked for efficient cooling.
Some of the most common thermostat issues include:
The thermostat is broken, not properly level, or dusty. The thermostat needs to be recalibrated. There is loose wiring causing a thermostat issue.
It's recommended that you service your home air conditioning system at least once every year. The same goes for your heating system.
The short answer: You can get away with running your AC without a filter for a short period of time. However, doing so for longer than 6-8 hours can hurt your system and decrease your home's indoor air quality.
Check these issues when the unit won't kick on: Check the thermostat and adjust the settings if it isn't set to Cool and an appropriate temperature setting to call for cooling. Examine the house circuit breakers for the AC unit and reset any tripped breakers. Check the air filter and replace the filter if it's dirty.
In general, wall and window air conditioning units with smaller capacities can typically run for up to eight hours at a time before they need to rest. Larger wall and window units have a longer running time of around 10 to 12 hours, depending on their cooling power.
Start by making sure you have it set to your desired temperature and that it's switched to the “cool” setting. Next, double-check your vents to ensure they're open and free from obstructions. If that doesn't work, remove your A/C filter, and inspect it for any dust or discoloration.
A bad thermostat can be detected when your AC or furnace is not turning on, your HVAC systems are not turning off, the thermostat not responding, your HVAC system is short-cycling, the room temperature not matching the temperature displayed on the thermostat, and the programmed setting resetting themselves.
There are many reasons your AC might not be cooling your home properly. The solution could be as easy as flipping a switch on your thermostat, cleaning a dirty air filter, or clearing debris away from your outdoor unit. There are also more complex problems that may need the help of a professional.
Clean your Air Filters, Vents, and Ducts – A clogged air filter will struggle to meet the thermostat's set temperature since the dirt and debris buildup prevents air from circulating through the vents. And as airflow into living spaces drops, so do comfort levels.
How Often Do I Need to Change Out My Air Filter? Generally, most air filter manufacturers and HVAC companies recommend changing your air filter every 90 days, or 3 months. That can change based on where your home is located (ex. dusty, dry climates), if you have any pets, and the age of your system and equipment.
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.
While you might be tempted to simply turn the AC off, it's actually better to adjust the temperature several degrees higher, by about 7-10 degrees. By installing a programmable thermostat and making this simple adjustment you can potentially save as much as 10% on your energy bill.