Mini-Mite™ Tube Furnace
Troubleshooting
19
10 Troubleshooting
WARNING!
Troubleshooting procedures involve working with high voltages which can cause injury or
death. Troubleshooting should only be performed by trained personnel.
This section is a guide to troubleshooting furnace problems.
Table 5. UT150 Controller Troubleshooting
Problem
Probable Causes
Solution
Controller reads P.Er.
Abnormal parameter value
Check controller parameter settings and reset to proper values.
Controller reads b. o
Input burnout
Check the sensor wiring, replace sensor if necessary.
Controller reads ooo.
PV exceeds effective range
Check the input type and range settings and correct them.
Controller reads UUU.
PV is below effective range
Check the input type and range settings and correct them.
Controller reads Err
Probable hardware failure
Call Service for controller repair.
The controller displays do not
illuminate.
The furnace is not connected to the power
supply.
Check furnace connection to power source.
Main switch is defective.
Replace power switch or controller.
Fuse(s) blown.
Replace fuse(s) and verify power connections.
Table 6. Furnace Troubleshooting
Problem
Solution
Furnace temperature runs away.
Check solid-state relay:
1.
Remove the controller from the furnace.
2.
Connect power to the furnace. If the heating unit heats, replace the solid-state relay.
Furnace does not heat
Front panel red indicator light is on:
1.
If
the controller output light is off, check that the setpoint temperature is higher than the furnace display
temperature.
2.
If the output light is on, disconnect power from the furnace and check the heating elements for continuity.
Front panel red indicator light is off:
1.
Check that the power switch is on.
2.
Check that the indicator lights on the controller display are on.
3. Check that the furnace door is fully closed.
4.
Check that the door interrupt switch at the middle front of the furnace is engaged when the furnace door is
fully closed.
5. Check the electrical wires for visible damage. Replace the electrical wires if necessary.
6. Check that the Alarm Setpoint on the controller is set higher than the operating temperature (refer to
Section 6.3 on page 5).
Summary of Contents for Mini-Mite TF550 A
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