2000 Hook-up Book

HOOK-UP DIAGRAMS Figure II-32 Draining Heat Exchanger under Constant “Stall” Condition with Pumping Trap in Closed Loop System a Low Temperature Sensor Spira-tec Loss Detector Thermostatic Steam Trap Strainer Running Temperature Control Valve Strainer Storage Tank Warm Up Temperature Control Valve Run Temperature Sensor Thermo static Air Vent Heat Exchanger Strainer Pressure Powered Pump Thermo Dynamic Steam Trap Motive Steam Supply Reservoir Sensor Pressurized Return System Check Valve Check Valve P 2 Drain to Safe Place

Figure II-31 Temperature Control of Warm-up and Running Loads at Storage Tank A control valve suitably sized to supply the start up load on a tank is often very much oversized for the running load, and this oversizing can lead to erratic control. In such cases, a large control valve may be used to meet the warm up load, arranged to close at a temperature perhaps 2° below the final control temperature. The smaller control valve meets the running load, and the supply is supplemented through the start up valve, only when the capacity of the smaller valve is exceeded.

Moisture Separator

Steam Supply

Spira-tec Loss Detector

Strainer

Float & Thermostatic Steam Trap

Condensate Return

P 1

Pilot Operated Temperature Control Valve

Moisture Separator

Strainer

Steam Supply

Float & Thermostatic Steam Trap

Hot

Strainer

Cold

Spira-tec Loss Detector

Draining L.P. Heat Exchanger to Overhead Return. Pressure at pump outlet P 2 always exceeds supply pressure P 1 to Heat Exchanger. Completely immerse control sensor without well, right at hot outflow. To prevent overheating, the sensor must not see a “dead” flow.

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