- Be sure air conditioner condensation drip tubes are flowing freely. If they're clogged, clear with wet/dry vacuum. To prevent mold in pipes, add a little chlorine bleach. - Trim shrubs away from heat pump compressor, and trim those blocking crawl space ventilation. - Cut back tree limbs that are touching roof. Be careful around power lines! - Flush water heater as needed. Be sure to turn off power to water heater before draining, and refill before restoring power. - Open and close cutoff valves to sinks and toilets. You don't want to discover during a plumbing emergency that valves are stuck.