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two pipeSteam Fan coil unit with Pneumatic controls
I've only been in the trade for about 3 years, and don't have much experience with steam. Do you have any idea on what would cause the steam in the return? I forgot to mention that the guts to the trap had been removed prior to my company getting the contract. It would make sense that the steam in the return line is stopping the supply steam from moving through the coil. I can't explain why when I broke the union no steam went through the coil..