Corrective maintenance, If oven heats but does not reach temperature, Changing heating elements – Henkel KHTF-600 User Manual
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3.
Check output side of fuse block for proper voltage. If fuses are bad, inspect oven wiring and
components for damage. Replace fuses.
4.
Check input and output voltages on temperature controller for proper voltage. If input voltage is
not present, check wiring. If input voltage is present and there is no output voltage, replace or
repair controller.
5.
If output voltage is present, check for voltage at contactor coil. If voltage is not present, check
wiring. If voltage is present at coil and contactor is in the open position, replace contactor. If the
contactor is in the closed position and there is no output voltage present, replace contactor.
6.
If the over temperature contactor is functioning, next check the relay operated by the temperature
controller for proper control voltage and proper load voltage on the input and output sides of the
relay.
7.
If there is no control voltage present at the relay, check wiring to the temperature controller and
temperature controller output voltage.
8.
If control voltage is present at relay, check voltage between relay output and common. If no
voltage is present between relay output and common, replace relay.
9.
If voltage is present between relay output and common, check wiring to elements, and element
continuity. Replace faulty wiring or elements.
NOTE: Temperature controller is equipped with an open sensor indicating light located in the digital
display area.
IF OVEN HEATS BUT DOES NOT REACH TEMPERATURE
One or more elements may be faulty. Check continuity and replace faulty elements.
Corrective Maintenance
CHANGING HEATING ELEMENTS
1. Disconnect power source and empty oven of flux.
2. Remove control box cover plate and remove wire connectors from element leads.
3. Element cover may now be removed with control box still attached. Note that the thermocouple
lead will pull form the thermowell. When replacing element cover, be sure thermocouple is
replaced in wall.
4. To remove wiring leads from elements place a one-fourth inch open-end wrench on square
portion of element terminal for a back up. Remove 10/32 hex nuts, washers and wiring leads.
5. From interior of oven, remove stove bolts, nuts, washers and wiring leads.
6. Install new elements and element hardware in oven, being sure element terminals are clear of
oven wall. Check wiring diagram or parts list for proper replacement elements.
7.
Reattach wiring leads to elements being sure to use a back up wrench when tightening.
8.
Replace element cover on oven being sure thermocouple is replaced in well and element leads are
pulled through control box access.
9. Reconnect element leads as per wiring diagram and replace control box cover plate.