Armstrong D1175-3 Float & Thermostatic Steam Trap is a B Series model engineered to automatically drain condensate from low‑pressure steam systems while preventing live steam loss. It is a 1" NPT unit employing a float and thermostatic control and features an integral threaded air vent for automatic air release. Constructed with a body available in cast iron or stainless steel, the trap is rated for a maximum of 15 psig (15 psi) and withstands temperatures up to 377°F (191°C). The 15B4 designation commonly accompanies this D1175-3 configuration, denoting the 1" connection and vent arrangement used on Armstrong's B/BI series traps.
