26 OVEN SYSTEMS
2.Check the input voltage on terminals L1 & L2
3.If no voltage is present, inspect the wire harness for damage or shorts (page 45).
4.If wire harness is intact and undamaged, the BMSC is damaged or defective and must be replaced (page
Accessing Parameters
WARNING: DO NOT perform this procedure unless instructed by TurboChef.Changing the parameters to other than those preset by TurboChef can damage critical oven components.
1.Open the right or left end bell depending on which BMSC requires testing
(page 1,
2.Locate the BMSC (page
3.Press the MODE key.
4.Use the 
keys to navigate the parameters.
5.Press the MODE key to access the parameter shown on the BMSC display.
6.Use the 
keys to manipulate the parameter.
7.Press the MODE key to return to the parameter selection.
8.Repeat steps
The Burner System
This section contains information about and testing procedures for the following components:
-Air Pressure Switch
-Burner Transformer
-Combustion Blower
-Modulating Gas Valve
-Ignition Module
Air Pressure Switch
The air pressure switch contacts close when a 0.1in WC (2.54mm WC) differential exists
between the two ports. The air pressure switch has one negative port and one positive. The air tube from the combustion blower is attached to the positive port. The air tube must not be dam- aged in any way (cracked or split). The connec- tion must be tight at the combustion blower and the switch itself to ensure proper operation of the air pressure switch.
Testing Procedure
1.Attach a digital manometer to the air tube coming from the combustion blower.
2.A reading above 0.1in WC (2.54mm WC) is required to close the contacts. If the reading is below 0.1in WC (2.54mm WC), check the combustion blower operation.
Burner Transformer
The burner transformer converts incoming line voltage to 24 VAC output.
Testing Procedure
1.Disconnect line voltage to the burner transformer.
2.Remove the burner transformer lead wires.
3.Check the resistance of the primary and secondary windings, refer to Figure 33, to determine if the transformer is functioning properly.
4.Set up the wire configuration for 208 or 240:
-208 VAC installation: connect wire B (blue) to wire C (blue). Figure 32, below, is configured for 208 VAC operation.
-240 VAC installation: connect wire A (red) to wire C (blue).
C
B
A
