51. Low Fluid Level Cutoff (Low Level Control)
a
Removal. Refer to Fig. 35 & 36 and remove the low fluid level cutoff.
NOTE
MAKE CERTAIN ALL HEAT TRANSFER FLUID IS REMOVED FROM EXPANSION TANK
BEFORE REMOVAL OF LOW FLUID CUTOFF.
1.
Loosen screws in cover; remove cover
2
Tag and disconnect all electrical connections.
3
Turn hex section with wrench, counterclockwise; remove control.
b.
Cleaning and Inspection.
1.
Clean the low fluid level cutoff with a cloth dampened in an approved cleaning solvent and dry
thoroughly.
2.
Inspect for corrosion, broken or defective switch and other damage. Inspect mounting hardware for
cracks, breaks, and damaged threads
3.
Replace any defective parts. Ref. Fig. 36.
c.
Installation. Refer to Fig. 35 and install the low fluid level cutoff in reverse order of removal.
52. High Temperature Limit Control
a.
On-Equipment Adjustment.
1.
This is an internally set control. An adjusting screw inside the case is turned to position the switch for
actuation at a specified temperature. Refer to Fig. 37 and adjust control.
2.
While hot oil heater is in operation and temperature control is set above high temperature required,
adjust high temperature control setting for shutoff. Maximum setting 4500F.
3.
If the high temperature control does not respond and actuate switch, replace the capillary tube and bulb.
4.
Following replacement of a new capillary, repeat adjustment for high temperature control setting.
5.
Reduce temperature control setting for operating temperature of hot oil heater below setting of high
temperature control.
6.
This high temperature adjustment should be made with the temperature control test (Para. 47).
b.
Removal. Refer to Fig. 1, Item 3 and remove the high temperature control.
1.
Loosen 2 screws in cover plate on top; remove cover.
NOTE: MAKE CERTAIN ALL ELECTRICAL POWER HAS BEEN TURNED OFF.
2.
Remove and tag electrical connections.
3.
Remove 2 screws from thermal element, Fig. 37, and remove thermal element by pulling down and
away from control.
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