Could you help us ID this old item or might have a PDF to describe it operation. It’s from an old vapor steam system. It has a ¾” NPT connection x 5-3/4” H & is inscribed with #5 Thermodisk, I-39, Jas. P. Marsh & Co.-Chicago. Not certain if it functioned solely as a vacuum breaker and/or an air vent. This was located in the boiler room atop the dry return before piping dropped into a boiler return trap arrangement.
PS CANNOT copy photo of device at this time. Uncertain how to attach file.
Thank you, Mike
This post was edited by an admin on December 6, 2012 6:48 PM.