Vulcan-Hart SG44 Gas Heater User Manual


 
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
b. Replace the temperature control
and check calibration as outlined
under SOILD STATE
TEMPERATURE CONTROL
CALIBRATION.
TEMPERATURE PROBE TEST
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
NOTE: The temperature probe used in conjunction
with the Solid State Temperature control is an RTD
(resistance temperature detector) of the Thermistor
type. As temperature increases the resistance value
decreases.
1. Remove the RIGHT SIDE PANEL.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the
CONTROL PANEL.
2. Place a shielded thermocouple in the geometric
center of the oven cavity and determine the
temperature in the oven cavity.
3. Remove the probe lead wires from the solid state
temperature control.
4. Test the probe with an ohmmeter.
A. If the measured resistance values are inside
the given tolerance then the probe is
functioning properly.
B. If the measured resistance values are
outside the given tolerance then replace the
probe and retest.
1) Check oven for proper operation.
5. Reverse procedure to install.
TEMP (°F) OHMS* TEMP (°F) OHMS*
77 90,000 360 822
240 4,077 380 656
260 3,016 400 529
280 2,266 425 424
300 1,726 450 334
TEMP (°F) OHMS* TEMP (°F) OHMS*
320 1,332 475 266
340 1,041
(*) Resistance in ohms ± 10%
GAS VALVE PRESSURE CHECK
Disconnect the
electrical power to the machine and
follow lockout / tagout procedures.
1. Turn gas supply off at manual shutoff valve.
2. Remove the RIGHT SIDE PANEL.
NOTE: If right side panel is not accessible, this
component can be serviced by removing the
CONTROL PANEL.
3. Remove the plug from the manifold pressure
port.
Fig. 43
4. Install hose barb adapter and attach manometer
tube.
5. Turn gas supply to the oven back on.
6. Plug the unit in and turn the power switch ON.
7. Set the temperature control to its highest setting
and allow burner to ignite.
NOTE: The burner must be lit during test.
NOTE: Accurate gas pressure readings can only be
made with the gas on and the burner lit.
SG SERIES GAS CONVECTION OVENS - SERVICE PRODCEDURES AND ADJUSTMENTS
Page 21 of 33 F45525 Rev. A (0315)