1 Technical Requirements - Pacific Gas and Electric Company

Vent and drain systems shall be sized so that the maximum time to drain any heat transfer section is 45 minutes and a maximum time to drain the entire HRSG from operating conditions of 4 hours. In no event shall the drain valves be less than 1½ inches NPS. Intermittent blow off is not acceptable as a means of draining the HRSG. ................
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