How Can I Tell if my AC is Leaking Freon?

Taken advantage of asks,

What is the better way to check a freon leak – a dye test, or an electronic device? I have had about five pounds of freon leak over the past nine months. My home warranty plan refuses to send out another company to check for the leak using the dye test. They say “wait 60 days & see if the leak can be found.” What do you suggest?

Our Answer

First off, you’re not the best person to be searching for a refrigerant leak – which, by the way, may or may not be freon depending on the age of your AC compressor. 
Rather than check for actual leakage, check for performance. Here’s how:
Measure the temperature of the air inside the house at a return duct, then measure it at a supply duct nearest to the air handler. If the system is performing normally, you should read a 12 – 20 degree differential. If the differential is less than twelve, you’re well within your right to demand repair. 
As far as your <a href="https://www.moneypit.com/home-improvement-contracts-guarantees-and-warranties/" target="_blank" rel="noopener noreferrer">home warranty company</a>’s refusal to address this problem, this is unfortunately somewhat typical, and I can only suggest you be very persistent with them, and always ask to discuss the matter with a supervisor. Good luck!