My A/C unit is running, but no cool air is coming from the vents!
This is a frequent issue with two general items you can easily check yourself before arranging a service call. The first thing you should do is check the furnace filter. A dirty filter can restrict air flow to the A/C. This can cause the evaporator coil to “freeze,” and possibly block all the air flow. This causes the ice buildup to get worse. If this is the case with your unit, you will need to shut off the A/C at the thermostat, change the filter, and then wait for the evaporator coil to thaw completely before using again. This can sometimes take up to one day. Check for water flowing at the outlet of the ¾” PVC drain line to see if the unit is thawing. Now you’re ready to restart the system and see if the problem persists.
If this does not fix the problem, you may have a leak in the refrigerant system. Low refrigerant pressure can cause the system to freeze over. Some units have a low pressure, or “loss of charge” switch that will shut the system down until the refrigerant is refilled to the proper level. You can try to check for loose valves or visible leaks, but a technician EPA-certified to handle refrigerant may be needed.