GUNDER 1RAF Series RETURN AIR FILTER GRILLE & 1RA Series FLAT RETUN AIR GRILLE

1RAF Series RETUN AIR FILTER GRILLE
HVAC intake filtered return air grille is a hinged, wall- or ceiling-mounted vent cover that draws indoor air back into the HVAC system while housing an air filter.
 It protects the system from dust, improves air quality, and allows for easy filter changes in living spaces rather than at the furnace. 

Key Aspects of Filtered Return Air Grilles:
Purpose: These grilles hold a filter, acting as the primary point to capture dust and particles before air enters the ductwork, which prevents the blower motor from becoming clogged or damaged.

Location: They are typically installed on walls or ceilings in high-traffic areas.

Design: They feature a hinged faceplate, allowing for easy access to change the filter without tools.

Filter Type: They usually accept standard 1-inch filters, though some are designed for deeper, higher-efficiency filters to increase surface area and airflow.

Efficiency & Maintenance: Properly sized grilles (often 
 per ton of AC) are essential for proper airflow. Using a filtered grille at the intake rather than only at the air handler helps keep ductwork cleaner. 

Using a filtered return grille instead of a standard, non-filtered grille prevents contaminants from entering the HVAC system, thereby increasing the system's longevity and efficiency. 

Filters & Filter Accessories sold separately.

1RA Series FLAT RETURN AIR GRILLE
HVAC intake flat non-filtered return air grille is a, usually white, metal vent cover with fixed slats used to pull, not push, air from a room back into the HVAC system. 
Unlike filter grilles, these do not hold air filters, meaning the filter must be located at the air handler. 

Key details:
Function: Covers the return duct opening on walls or ceilings, allowing air to flow freely back to the HVAC unit.

Design: Typically has "fixed" or stationary angled fins (louvers) to maximize airflow and minimize noise.

"Non-Filtered": Does not feature a hinge or housing to hold a replaceable air filter, allowing for a flush, low-profile look against the wall.

Purpose: Ensures proper, unobstructed air circulation back to the unit, balancing pressure and aiding in heating/cooling efficiency.

Installation: Usually, these are screwed directly onto the drywall over the duct opening, often in hallways or high ceiling areas. 

These grilles are designed for high-flow, unrestricted air movement, relying on a central filter located at the furnace or air handler

Filters & Filter Accessories sold separately.