1. Clean or replace furnace and/or AC filter. 

2. Check and clean mechanical ventilation system (HRV/ERV). Check your manual and follow manufacturer's recommendations.

3.  Clear air intakes, exhaust and meters of debris, nests, etc.

4.  Check gutters and downspouts and clean if needed.

5.  Be sure to check settling after spring thaw.

6.  Open outside hose connection.

7.  Check and clean central air conditioning system.  Check your manual and follow recommendations.

8.  Check landscaping springlers to ensure proper alignment.  DO NOT let them soak your siding or foundation.

9. Clean A/C condenser.

10. Inspect pressure & temperature valve on water heater.

11. Maintain proper grades for drainage throughout the property.

12. Inspect roof for damage and make repairs when necessary.