Air conditioning repair. No AC call. Found the Nest thermostat showing no power to the RH plug. Went down to the furnace. After the diagnosis, found that the transformer had failed. Replaced the transformer to regain power to all the equipment. **Customer renewed the VIP maintenance program. Used one visit today and performed an air conditioning tune-up and safety inspection. Tested all mechanical components. Found the contactor very corroded. Replaced unintended 1+shunt. The capacitor was in the accurate range. R22 refrigerant levels were in the accurate efficiency range. Tested the compressor amperage and the fan motor amperage, and they both were in the accurate efficiency range. The AC system is clean, cooling, and operating properly at this time.