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Heating Tappings on an Weil McLain Model H-4 Boiler
I have come across an old steam boiler, a Weil McLain Model H-4 (estimated install year 1969) that has two domestic cold water tappings on the boilers left side, that a previous installer piped the house domestic cold water into and out of the boiler at these points.
It took some time for me dig up some old literature about the model H boiler, but I can not with 100% certainty answer the following two questions, so here they are:
(1) Does the boiler require the domestic cold water feeds for any reason?
(2) If the two tappings are disconnected and plugged will that result in a failure of an interior coil, tube bundle or tank burning up? I attached some literature that I found, but the manufacturer doesn't provide any details to what is going on inside the boiler. It appears that the domestic water was piped in such a manner to use the boiler as pre-heater to the incoming domestic water.
Without knowing exactly what is going on inside the boiler, I can not advise whether these line can safelty be disconnected from the mechanical system. I welcome any insight or discussion on this matter.
I attached the literature and a couple of pictures, along with a online piping schematic.