Do not use this item for any installation or repair of potable water applications. This product does not comply with the "Safe Drinking Water Act," which requires that products meet low-lead standards in order to be used in systems providing water for human consumption (drinking or cooking). This item is for non-potable (non-human consumption) water applications only.


Durable forged brass body construction. Series AS-MB does not require laminar flow for efficient separation and elimination of entrained air in hydronic heating systems. There is no minimum inlet/outlet piping length required for proper operation of AS-MB Microbubble Air Separators.

Rugged, polyphenylsulfone (PPSU) coalescing media withstands petroleum based cleaners, glycol anti-freeze and temperatures up to 240º degrees in closed-loop heating systems, and methanol based anti-freeze solutions in ground source heat pump loops.

DuoVent air vent assembly consists of a brass cover, air vent with silicone rubber seal, shutter, polyethylene float with valve plug, automatic vent with black cap and manual vent with red cap. Air vent assembly has a high capacity and high temperature rating and is ideal for use with glycol systems or for use as an anti-vacuum device.

Fully serviceable - can be disassembled for inspection and cleaning.

½" FPT bottom tapping for use with Series RBFF Residential Boiler Fill Fitting

AS-MB FL flanged model can be used with Series PIPF

Isolation Pump Flanges with Purge Port & Swivel Flange to create a compact system purge/air elimination module.
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Connection Type:
Female Threaded
Max. Working Pressure:
150 psi
Max Temp (F):
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