Yes, I'm aware that companies sell HEPA cabin air filters for vehicles. But, is it safe to install a HEPA cabin air filter on a vehicle who's HVAC system wasn't designed for HEPA air filters?
https://www.engineersedge.com/filtration/hepa_filter_pressure_drop_considerations.htm
By design, HEPA air filters will create resistance to flow, and a high differential pressure drop will exist across the filter. Most HEPA air filter manufacturers literature suggests replacement of HEPA air filters when the resistance due to dust loading has reached 2 in.wg.
So if your car's HVAC is designed for high airflow and you slap a HEPA filter on it, are you adding more stress and wear on the system? Seems like it's the exact same problem of installing an overly restrictive filter on your home's HVAC return vent.
2 Comments
empireOfLove2@lemmy.dbzer0.com · 7 pts · 4d
It's "safe" aka not likely to wear anything out faster, since most vehicle hvac components run at a steady state no matter the input load, but you will likely see significantly reduced performance. Vehicle HVAC is always fighting a losing battle against a barely-insulated tin can that is about 50% thermally transparent glass. Any slight reduction in airflow is going to make it less comfortable and likely way worse at maintaining any in-cabin set temp.
I guess worst case, reduced airflow over the A/C evaporator could cause the compressor clutch to cycle on and off more frequently when running A/C.
Vehicles specced with HEPA filters from OEM usually have significantly larger filter area, to compensate for how restrictive the media is. If the OE filter isn't a HEPA I would not put one or any other super special "high efficiency" filter in.
genuineparts@infosec.pub · 2 pts · 4d
Shadetree guy here, so you know take with grains of salt.
Is it unsafe? Nah. You might add additional wear on things like the cabin fan and depending on the age of your vehicle you might have a resistor block to control fan speeds, if you reduce airflow it could get hotter and fail faster.
But first off you probably are not adding an additional HEPA filter to the existing cabin filter, so the increase in airflow resistance probably isn't all that much especially since some people let that filter sit there until it is nearly plugged and the systems can survive that too.
Well except the house has way more airflow and it might throw off the air balance for the building. Your car A/C and cabin fan will be fine.