Same-day AC repair
By Arman Hakobyan, lead technician1 min read
Close windows, set the system to recirculate, and run the fan continuously with a MERV 13 or higher filter if your system can handle it, as the EPA recommends. Seal leaky return ducts that pull in attic air, and use a portable HEPA cleaner in bedrooms. Avoid ozone-producing air cleaners.
On a smoke day
- Close windows and doors; switch any fresh-air intake or whole-house fan off.
- Set the thermostat fan to On so air passes through the filter continuously.
- Use a MERV 13 filter if the system can move enough air through it; replace it after heavy smoke.
- Run a portable HEPA air cleaner sized for the room where you sleep.
- Avoid burning candles, frying or vacuuming without a HEPA vacuum, which add particles indoors.
Before fire season
- Have a technician measure static pressure to see what filter your system can handle.
- Consider a 4 to 5 inch media filter cabinet, which filters better with less airflow loss than a 1-inch MERV 13.
- Seal the filter frame and return ducts so air cannot bypass the filter.
- Stock spare filters; they sell out during big fires.
Questions
Will a MERV 13 filter hurt my system?
It can if the system was not designed for the extra resistance. A static pressure test answers it; a deeper media filter usually solves it.
Do ionizers or ozone generators help?
Ozone generators should not be used in occupied homes. We recommend filtration and sealing, which have the strongest evidence.
Need it fixed today?
Open Mon-Sun 7 AM-9 PM. 24/7 emergency line.
Arman leads diagnostics at Airwork. He has spent nine years on residential systems across the San Fernando Valley and the foothills, from 1950s ranch houses with attic ducts to new heat pump installs, and writes our guides from what he sees on calls.
Airwork Heating & Cooling, Burbank, CA (CSLB #1148919). Published .More guides
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