Vacuum Breaker on a Steam Heat Exchanger

KT1776

I have a client with a steam-to-hotwater converter that uses the building's central steam supply. The building's steam system operates with a vacuum pump return system. But there is a vacuum breaker installed on the steam supply inlet to the converter. My understanding is that you don't use vacuum breakers when you have a vacuum pump.
You can see the breaker on the top right of the picture.

mattmia2

Knowing very little about commercial systems, isn't the vacuum only on the return if the steam traps are functioning properly?

EBEBRATT-Ed

When the steam control valve closes and there is steam in the heat exchanger a vacuum can form and not allow the condensate to drain this can cause water hammer and damage to the hx. If the traps are operating properly they should only open to pass condensate or air and close when steam is present.

109A_5