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    Before when the returns drained
    Added: 2020-05-09 | Category: one | Comments: 0

    Before, when the returns drained directly into the boiler, the back pressure of the boiler created a balance between the pressures on the supply and the returns with vented feed units, there is no back pressure from the supply steam will be more than happy to push through the water vapor seals and show up at the receiver vent pipe, creating water hammer all along the way. Owning a house is.