Was here for a package cleaning and to clean the mini split air conditioner. Performed furnace cleaning. Found moderate to heavy rusting in the heat exchanger. Electrical components are original. Performed combustion test. The furnace is 16 years old. Recommend continuing to get cleanings to monitor the heat exchanger. The furnace is running normally at this time. Performed air conditioning cleaning on the mini split unit. Found that a mouse got into the electrical and was causing the air conditioner to not start up. Cleared out the mice. No damage to the electrical. Cleaned and cycled the air conditioner. The air conditioner is running normally at this time. Performed air conditioning cleaning on the Armstrong unit. Checked the indoor coil for leaks. Found indications of a leak in the indoor coil. Found that the air conditioner is low on r-22 refrigerant. This unit is 16 years old. Recommend my supervisor give the customer a call.