CLEAN AND CHECK HEATING UNIT. WTY BY BACK 3 TON 3 P PIG 5 YR P 1 YR L. INSTALLED 3 TON HEATING UNIT. MADE SURE UNIT WAS INSTALLED PROPERLY AND WORK AREA WAS CLEAN WHEN FINISH. CLEAN AND CHECK BURNERS AND BURNER OPERATION. CHECK HEAT EXCHANGER. CHECK MANIFOLD GAS PRESSURE AND FOR PROPER VENTING. CHECK THERMOSTAT, AIR FILTER, AIRFLOW, AND ALL ELECTRICAL CONNECTIONS. EVERYTHING IS RUNNING GOOD.