2000 Hook-up Book

Both HP and LP mains often must be drained to a condensate return line at the same elevation as the steam line. The best location for the traps is then below the steam line, with a riser after the trap to the top of the return line. a aaa Figure II-5 Draining Steam Mains to Return Main at Same Level Spira-tec Loss Detector Thermo-Dynamic Steam Trap with Integral Strainer Connector Strainer Condensate Main HP Main LP Main

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Check Valve

Check Valve

Spira-tec Loss Detector

Float & Thermostatic Steam Trap

Supervised Start-up Valve

HOOK-UP DIAGRAMS

Spira-tec Loss Detector

Figure II-6 Trapping Hook-up for Start-up of Steam Main

Thermo-Dynamic Steam Trap with Integral Strainer

For supervised startup of steam mains, a manual bypass is fitted so that condensate can be drained by gravity while the line pressure is too low for it to be handled by the trap at an adequate rate. If a second trap is fitted in the bypass line, a similar hookup is obtained which is suitable for automatic startup.

Thermo-Dynamic Steam Trap with Integral Strainer

Spira-tec Loss Detector

Supervised Start-up Valve

Condensate Return

Figure II-7 Hook-up with Condensate Return Line at High Level

Check Valve

Thermo-Dynamic Steam Trap with Integral Strainer

Spira-tec Loss Detector

Often the normal trap discharges to a return line at higher elevation. The startup trap must always discharge by gravity so here it is separated from the “normal running” trap. A Thermoton is used so that it will close automatically when the condensate temperature shows that warm up of the main is nearing completion.

Liquid Expansion Steam Trap

Drain

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