Arrived onsite for no AC service call. Also discussed the basement furnace ductwork. Performed diagnostic on the AC system, found the system low in 410a refrigerant with the indoor coil freezing up. Estimate about 75 percent low on refrigerant. 3.5 ton system with 10 pounds of refrigerant. Used electronic leak detector inside and outside but it did not detect the leak. Inside coil is rusted and likely to be source of leak but could not determine. Attic crawl space will require floor boards for repair or air handler replacement. System could possibly be under warranty. Will contact Lennox during business hours. Then provide next steps to the homeowner.
