J52 Datasheet, PDF (5/8 Pages) Magnetrol International, Inc. – J52 Refrigerant Level Switches

TROUBLESHOOTING
Usually the first indication of improper operation is failure of
the controlled equipment to function, i.e. pump will not start
(or stop), signal lights fail to light, etc. When these occur,
whether at time of installation or during routine service there-
after, check the following potential external causes first.
— Fuses may be blown.
— Reset button(s) may need resetting.
— Power switch may be open.
— Controlled equipment may be faulty.
— Wiring lines leading to control may be defective.
If a thorough inspection of these possible conditions fails to
locate the trouble, proceed next to a check of the controls
switch mechanism.
1. Pull disconnect switch or otherwise assure that electri-
cal circuit(s) through control deactivated.
2. Remove switch housing cover.
3. Swing magnet assembly in and out by hand to check
carefully for any sign of binding. Assembly should
require a minimum of force to move it through its full
swing.
4. If binding exists, magnet may be rubbing enclosing tube
or pivot sockets may be overly tight. Readjust pivot
sockets as required until a slight amount of side play is
evident. If magnet is rubbing, loosen magnet clamp
screw and shift magnet position.
5. If switch magnet assembly swings freely and mechanism
still fails to actuate, check installation of control to be
certain it is within the specified three degrees of vertical
(use spirit level on side of enclosing tube in two places,
90° apart).
6. Check the continuity of microswitch with ohmmeter.
Replace immediately if defective.
NOTE: As a matter of good practice, spare switches should
be kept on hand at all times.
If switch mechanism is operating satisfactorily, a test of the
complete controls performance is the next likely step.
1. Reconnect power supply and carefully actuate switch
mechanism manually (using a nonconductive tool) to
determine whether controlled equipment will operate.
CAUTION: With electrical power “on”, care should be
taken to avoid contact with switch leads and connections
at terminal blocks.
2. If controlled equipment responds to manual actuation
test, trouble may be located in the level sensing portion
of the control (float, stem, and magnetic attraction
sleeve).
NOTE: Check first to be certain refrigerant is entering float
chamber. A valve may be closed or pipe line
plugged.
3. Depressurize and remove E-tube, proceed to check
level sensing action by removing switch housing assem-
bly, as described in “Differential Adjustment” instruc-
tions.
4. Inspect attraction sleeve and inside of enclosing tube
for excessive corrosion or solids buildup which could
restrict movement, preventing sleeve from reaching field
of switch magnet.
5. If differential adjustment has been changed in the filed
by repositioning the lower jam nuts on the float stem,
check for tightness and position of the jam nuts.
NOTE: Differential adjustment affects a change in the
amount of level travel between “switch-on” and
“switch-off” actuations. Do NOT attempt adjustment
without first consulting factory for assistance in
computing level differential change for your control.
6. Check float to be certain it is buoyant in the refrigerant
(float chamber must have adequate refrigerant level). If
float is determined to be filled with liquid or collapsed, it
must be replace immediately. Do NOT attempt to repair
a float.
If all components in the control are in operating condition,
the trouble must be (and should be) located externally to the
control. Repeat inspection of external conditions previously
described.
NOTE: When in doubt about the condition or performance
of a Magnetrol control, return it to the factory. See
“Service Policy” on the back page.
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