MST21 Balanced Pressure Thermostatic Steam Trap

Spirax Sarco MST21 Steam Trap Features:
Available in 1/4″ or 1/2″ NPT
Available with 40°F, 18°F or 7.5°F subcool discharge elements
Full Stainless Steel Construction (Body, Capsule, and Seal)
Offered in standard and high-capacity
Serviceable Unit
Withstands water-hammer
Can be installed horizontally or vertically
Max Operating Pressure (PMO): 304 psi (21 bar)
Max Operating Temperature (TMO): 518°F @ 300 psi (270°C @ 21 barg)

The Spirax Sarco MST21 Steam Traps are a balanced pressure thermostatic steam trap featuring entirely stainless steel construction,
including the body seal. The welded stainless steel element is self-adjusting over the entire operating pressure range and will
discharge condensate at approximately 18°F (10°C) below saturated steam temperature on the standard Fill trap. Options are available
for a 40°F (22.2°C) or 7.3°F (-4°C) below steam discharge. The 7.5°F version is also referred to as the “near to steam” (NTS) option.
The MST21 Stainless Steel Steam Traps are rated for service up to 518°F @ 300 psi (270°C @ 21 barg) and will tolerate water.
The MST21 can be easily disassembled for servicing by unscrewing the body.

The MST21 steam trap is ideally installed vertically in line with the inlet at the top and the outlet at the bottom.
This will ensure that it is self-draining. However, it is also suitable for use in horizontal pipelines. If fitted in a horizontal line,
the trap should be preceded by a short drop leg. The trap will be piped inverted (outlet vertical up) when used as an air vent (NTS-Fill
recommended). Full port isolating valves should be installed upstream and downstream of the trap regardless of installation position.
Can be used on tracing, drips, sterilizers, and a low-capacity air vent.