Armstrong International D41790 Air Vent

The Armstrong International D41790, also identified as the AV-13 brass air vent, is a specialized automatic air vent designed for hydronic heating systems and hot water service. Featuring a dual-connection design with 1/2" female NPT and 3/4" male NPT ports, this float-actuated valve effectively manages air binding by purging accumulated air during system operation. Constructed from high-grade brass, the unit is rated for operating pressures up to 150 PSI and temperatures reaching 240°F. The D41790 float vent utilizes a high-leverage mechanism to ensure positive closure against the viton seat, preventing water leakage while allowing non-condensable gases to escape. This is a critical component for maintaining hydraulic balance and preventing pump cavitation in commercial piping loops. Contractors should note that the AV-13 is suitable for water and other non-corrosive liquids where a compact air eliminator is required for continuous venting.

• Dual-threaded connection (1/2" FNPT x 3/4" MNPT) provides versatile installation options for manifold or riser mounting.
• Robust brass body construction ensures durability in high-cycle hydronic applications.
• Internal stainless steel float and lever mechanism resist fouling and corrosion.
• Rated for 150 PSI maximum operating pressure, making it compatible with high-head commercial pump systems.
• Optimized for HVAC air elimination, reducing noise and improving heat transfer efficiency.

What is the maximum operating temperature for the Armstrong AV-13?
The D41790/AV-13 is designed for hot water service with a maximum temperature rating of 240°F (115°C).

Can this vent be used in steam systems?
No, the AV-13 is specifically engineered for liquid service only. Do not use this model on steam lines.

Is the D41790 air vent field-serviceable?
Yes, the cap can be removed to inspect the float and seat for debris, though regular system straining is recommended to prevent clogging.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.