Table 17-5. Electric Winterization Heater Control Box Testing
Probable cause
Step
Test condition
Required result
for improper result
Check out procedure
1.
Position heater
Heater control box
Defective fuse F301.
Check continuity of fuse.
control box
indicators DS301
There should be con-
switch to ON
should illuminate.
tinuity.
and apply 230
Vat. Open
Defective switch 301.
Check continuity of switch
switch S2; see
when positioned to ON.
figure 17-5.
There should be con-
tinuity.
Defective circuit breaker CB301.
With ohmmeter, check
circuit breaker for
correct operation.
Defective indicator 301.
Check indicator for con-
tinuity.
There should
be some continuity.
Defective diodes CR301, CR302,
Check diodes with
CR303 or CR304.
ohmmeter.
2.
Close switch S2.
Voltmeters V2
Defective transformer T301.
See transformer test,
and V3 should
paragraph 17-18.
indicate 230
Vac and volt-
Defective relay K301.
Check relay per
meter V1
paragraph 17-18.
should indi-
cate approxi-
mately 30
Vdc, and DS302
should illumi-
nate.
17-14
