Hello Bob!

https://ibb.co/HXzNVtY

Attached I've created a minimum working example of what seems to me like different boilers creating different types of steam. The steam pipes can be connected and the steam-fluids will "mix", but as long as a boiler 2 is producing steam to the pipe network, the metal mixing furnaces will not accept the steam as input for glass processing. What is going on here?? bug?

P.S. The temperatures are above the 165 C threashold for glass processing.

glass needs steam? in my mods, you just put quartz into a furnace to get glass.
are you working with other mods? it's possible that if someone else has a recipe for crafting glass that they've set the requirement to temperature = 165, rather than using minimum temperature.

Oh, I'm sorry! I have other mods but the recipe didn't mention it... I will look into this further and post a bug report for the appropriate mod! :)