Unit blowing air, but not cooling down house. Thermostat set at 70 degrees, but will not go below 74 degrees. Check air filter - clean. Check evaporator coil - clean. Perform leak check on evaporator coil - no leaks. Leak check on Schrader valves - high side Schrader valve is leaking. Replace Schrader valve on high side and hook up gauges to see pressures - low on R22. Add 2 lbs of R22 - house cooling. Suction line is cold/sweating - 19 degree split