Removed old package unit and installed new carrier 4 ton gas package unit. Installed curb adapter to properly fit new unit. Installed new thermostat. Reconnected high voltag, low voltag, drain line, and gas line. Tested system operations in heating and cooling. System has 2- 16x25x2 filters.
Call for no heat, system was calling on arrival, checked system on the roof and found that it was giving a 3 blink code, open roll out or safety switch, did a safety inspection on the heat exchangers and found that Cells 1, 2 and 3 are compromised, system is beyond life expectancy and repairs will exceed the value of existing system, it is recommended to replace and upgrade system.