Middleby Marshall PS200-R68 Section Operation, Ii. Operation, Initial Start Up, Daily Start Up

SECTION 3

OPERATION

II. OPERATION

A. Start Up Procedures -- Gas Heated Ovens

4. The temperature controller should be set at your

desired baking temperature. See section on bake times to determine desired temperature.

Initial Start Up

1.Check that manual gas shutoff valve is on. Valve is located below machinery compartment. See Figure 2-12.

Daily Start Up

1. Turn blower switch to the on (I) position. This

starts the main blower fan and the cooling fan. The blower circulates air through the air fingers and must stay on during the cooking or baking process.

2.Check to see if the cooling fans (see Figures 1-4 and 1-6) are operating when the blower switch is turned on (I). The cooling fans cool the electrical components and burner blower motor. The cooling fan, located at the rear of the machinery cabinet blows air into and through the cabinet. Air is exhausted out the back of the oven. A cooling fan is also located in the bottom of the control box to draw air through the rear louvers and out the bottom.

Clean the cooling fan grills and louvers daily.

NOTE: For complete temperature controller operation instructions refer to Step B.

5. Turn the heat switch to the on (I) position. This will

complete a circuit which supplies power to the burner. When an oven that has not been in operation for approxi- mately 1/2 hour is turned on it goes through a 15 second purge cycle. The burner blower motor will not operate during the time the main fan is purging the oven. After 15 seconds the burner blower motor starts, which can be detected by feeling a slight vibration when touched. This should permit the burner to light.

When in operation, the burner is either on low or high flame. A flame sensing electrode must be satisfied to keep the pilot and gas valve open. If for some reason the pilot flame is extinguished, the pilot will try to relight for 90 seconds. If the pilot does not relight in 90 seconds the oven will go into automatic safety lockout.

To relight the oven the heat switch must be turned off

for 5 minutes and then repeat the oven start-up proce- dure.

IMPORTANT NOTE: The cooling fan will operate when			6. Close front window.
the blower switch is turned on (I). It must operate to keep
			7. Oven will reach a baking temperature of 500° F (260°
the machinery cabinet below 140°F. (60° C.).
			C) in approximately 10 minutes. Allow the oven to cycle
WARNING: IF FAN BLADE IS NOT ROTATING, BRO-			for 30 minutes after it has reached desired bake tempera-
KEN OR IF FAN ASSEMBLY IS MISSING FROM MAIN			ture and the oven is now ready for baking.
BLOWER MOTOR SHAFT, DO NOT OPERATE OVEN.			Power Failure
REPLACE COOLING FAN BLADE BEFORE OPERAT-
			In case of power failure, turn off all switches, open oven
ING OVEN. Serious damage could be done to the burner
			window and remove product. After power has been
blower motor and/or the solid state electrical compo-
			reestablished follow normal start-up procedure.
nents if oven is operated while cooling fan is not running
or vent grill is plugged.
3. Turn the conveyor		switch to the on (I) position.
This now starts the conveyor belt moving through the
oven. Set conveyor speed digital control for desired bake
time	.

CAUTION

The burner will not operate and gas will not flow through the burner without electric power. No attempt should be made to operate the oven during power failure.

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