Prepping Your HVAC for Sacramento Wildfire Smoke Season

July 30, 20265 min readPerma Services HVAC

Sacramento averages 2–4 weeks of unhealthy air quality every summer from Northern California wildfires. Your HVAC system is your best defense — if it's set up right.

Upgrade your filter (but not too much)

  • MERV 13 is the sweet spot: captures wildfire smoke particles without choking most residential systems
  • Do NOT install HEPA filters in a standard return — they can starve the blower and burn out the motor
  • Change filters every 30 days during smoke events, sometimes weekly

Seal the envelope

  • Check that all return-air panels are gasketed and screwed shut
  • Look for holes around the air handler in the attic or closet — smoke gets pulled through them
  • Close outdoor air dampers on ERVs and fresh-air intakes during smoke events

Consider an IAQ upgrade before September

  • Media air cleaners (5" filters) — much better dust and smoke capture, less pressure drop
  • Whole-home HEPA bypass units — the gold standard for smoke
  • UV lamps for microbial control on the coil
  • Portable HEPA units for the bedroom as a backup

During a smoke event

  • Run the fan continuously to keep filtering (Auto → On)
  • Keep windows closed even at night
  • Set the thermostat 2–3° cooler so the system runs more often
  • If the outdoor unit is covered in ash, rinse it (power off first)

Frequently asked questions

Can my HVAC filter smoke on its own?+

With a MERV 13 filter and sealed ductwork, yes — well enough to keep indoor AQI 60–80% lower than outdoor.

Are portable air purifiers enough?+

For one room, yes. For a whole house, upgrade the HVAC filtration too.

Do you install whole-home HEPA systems?+

Yes — we install and service bypass HEPA units and 5" media cabinets across Sacramento.

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