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Watts cast iron air separator, transparent finish, in-line configuration with NPT connections

Watts

Watts AS-M1 T Air Separator Cast Iron 80 psi 275F

SKU CH-TZFT-6366T

In-line air separator for water systems with cast iron body, 1 in NPT inlet, 1 in NPT female vent and 1/2 in NPT female expansion tank port, rated 80 psi at 275F

  • ColorTransparent
  • Removes trapped air for efficient water systems
  • Cast iron body handles 275 °F and 80 psi pressure
  • In-line NPT connections simplify installation in existing pipework
  • Female 1 in inlet and vent ports fit standard fittings
  • Integrated ½ in expansion-tank port adds system flexibility

Watts Air Separator for Hydronic Systems

The Watts AS-M1 T is a cast-iron air separator rated for 80 psi and 275F water service. It removes entrained air from closed-loop hydronic piping through an in-line configuration. The body includes a 1-inch NPT female air vent connection and a 1/2-inch NPT female expansion tank port. This new component is built for commercial and residential heating installations.

In-line integration with standard NPT piping

The separator installs directly into 1-inch NPT female inlet and outlet connections without special tools or adapters. Its integrated expansion tank port frees up a separate tank fitting on the boiler or piping header. The 1-inch NPT female air vent connection accepts standard automatic or manual vents. Cast-iron construction handles the pressure and temperature ratings without additional reinforcement.

Suited for hydronic installers needing integrated

This unit suits contractors who want a single component that separates air and provides an expansion tank connection in one casting. It is not for systems operating above 80 psi or 275F. Installers requiring copper or stainless steel bodies, larger connection sizes, or horizontal-only mounting should look at other designs.

Highlights

  • Removes trapped air for efficient water systems
  • Cast iron body handles 275 °F and 80 psi pressure
  • In-line NPT connections simplify installation in existing pipework
  • Female 1 in inlet and vent ports fit standard fittings
  • Integrated ½ in expansion-tank port adds system flexibility

Specifications

ColorTransparent
BrandWATTS

Questions about this item

What is the maximum working pressure before the cast iron body reaches its limit?

The cast iron body is rated for 80 psi maximum working pressure.

How hot can the water get during continuous operation without exceeding the temperature limit?

The unit handles water temperatures up to 275 °F during sustained use.

Which NPT threaded connections must already be present on the piping for this in-line separator to install?

It requires 1 in female NPT inlet and outlet plus 1 in female NPT air vent and 1/2 in female NPT expansion tank ports.

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