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Consequences of No Air Intake Filter

No Air Intake Filter
No Air Intake Filter = Wasp Nests and Debris
No Air Intake Filter
No Filter = Mud Dauber Nests
No Filter
Common No-Filter installation

HomeMade Air Intake Filters

Homemade air intake filter
Needs to be removed, washed and replaced every 60-90 days
Freshly washed homemade air intake filter
Freshly serviced homemade filter
HomeMade Polyester Filter
Scissors-Cut homemade polyester filter before installation

Unserviced HomeMade Air Intake Filters

HomeMade Air Intake Filter in Repurposed Clothes Dryer Hood.
This HomeMade Air Intake Filter of Hog's Hair has been operating about two days.
Unserviced HomeMade Air Intake Filter
HomeMade Air Intake Filter That Needs Service
HomeMade Air Intake Filter Needing Service
HomeMade Air Intake Filter after 60-90 Days

Unless homemade filters are well supported by rabbit cage wire behind them, powerful 120 volt fans sometimes suck heavily loaded homemade filters right out of the filter  holder and into the fan itself to cause fan issues. I have seen a case where four filters had been sucked into the Fan causing balance and vibration/noise issues. Maintenance folks just thought that someone had forgotten to install the filter and installed a new one each time.

SmartVentilation's Custom Designed, Factory Made Type II and Type III Filter Comparison with a HomeMade, Scissors-Cut, Polyester Filter

Filter Comparison
Although manufactured, first class air intake filters are readily available from at least three manufacturers, most ventilation/radon systems have no filter or a homemade filter that must be serviced every 60-90 days.. Most installers do not advise the customer of the filter that will be installed likely for reason that the customer would not be satisfied with the offering.

A SmartVentilation Type III Retrofit Kit Can Easily Replace HIgh Maintainence HomeMade Filter Installations.

MERV 14-15 fir filter, 18-24 month service life
MERV 14-15 filter quality assures removal of nearly all toxins and particles including PM2.5, viruses, bacteria, wildfire smoke, valley fever spores, pollen, red tide and blue-green algae irritant and neurotoxin particles

The filter below has been operating in a Daisy Ductless for two years. Note the Soot (PM2.5 ) that has been blocked from entry into the home to darken walls and enter into the lungs of the occupants. NOTE: There is emerging evidence that PM2.5 carries radioactive hitchhikers that make it into the brain through contact with the hypothalamus where they permanently remain, emitting radiation into brain tissue. Some researchers have concluded that onset of Alzheimer’s may be delayed by a decade or more by MERV 15 filter-blocking PM2.5 from entering the indoors where most of us spend 90% of our time. (Filter Partially Extracted) This filter has become radioactive and must be disposed of properly

SmartVentilation Type III Filter Loaded with dirt and PM2.5 after being in service for two years