50. Pressuretrol
a.
Removal. Refer to Fig. 1, Item 4, and Fig. 34; remove the pressuretrol.
1.
Loosen four screws in cover plate; remove cover plate.
2.
Loosen nut on pressure line at bottom of pressuretrol.
NOTE: SHUT VALVE OFF BEFORE REMOVING PRESSURE LINE.
3.
Disconnect electrical connections.
4.
Remove mounting screws; remove pressuretrol.
b.
Cleaning and Inspection.
1.
Clean the pressuretrol with a cloth dampened in an approved cleaning solvent and dry thoroughly.
2.
Inspect for corrosion, broken or defective snap switch, and other damage.
Replace a defective
pressuretrol.
c.
Installation. Refer to Fig. 34. Install in reverse order of removal.
d.
Adjustment.
1.
Refer to the adjustment points and setting indicators, Fig. 34.
2.
NOTE:REFER ONLY TO THE POUNDS PER SQUARE INCH SCALES.
3.
Set the bellows, Item 11, until the low cutoff pressure is 25 PSI.
4.
Set the differential adjusting screw, Item 4, until the differential pressure scales reads 2 PSI.
NOTE:
WHEN PROPERLY ADJUSTED, THE PRESSURETROL WILL SHUT DOWN THE HOT OIL
HEATER WHEN THE HOT FLUID PRESSURE LOWERS TO 5 PSI AND ALLOWS THE HEATER
TO BE RESTARTED WHEN THE PRESSURE RISES TO 7 PSI.
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