envelopelearning@mainstreamcorporation.com phone303-912-4833
The filter replacements are for the Zehnder ComforAir ERV Devices. Two filters are needed to replace all filters in the units at the same time.
G4 Filter, MERV 8 - winter filter for supply or exhaust, or bypass filter for summer operation - $16 for ComfoAir Q unit.
F7 Filter, MERV 13 - summer pollen filter for supply only - $19 for ComfoAir Q unit.