Spirax-Sarco TD42L Thermodynamic Steam Trap TD42L

Spirax-Sarco TD42L is a compact, maintainable 1/2" thermodynamic steam trap from Spirax Sarco, designed for main-line drainage in steam systems and featuring stainless-steel construction with ENP nickel plating on the outer surface for corrosion resistance. The 1/2" NPT connection model operates up to 600 psig (41 bar) and temperatures up to 400°F (204°C), using a repairable thermodynamic mechanism to discharge condensate with minimal steam loss, and it includes an anti-airlock disc to vent air and prevent air binding. The TD42L family employs an inline horizontal flow pattern with a low-capacity design suitable for steady condensate removal, while other TD42 variants can be supplied with a blowdown valve. Typical weight for the 1/2" TD42L is about 20 lb, and its footprint fits standard steam-trap piping layouts. Common applications include condensate drainage from steam headers and other steam-using equipment where reliable, low-maintenance condensate removal is needed without excessive steam loss.