Middleby Marshall PS200-R68 Section Installation, V. Ventilation Guidelines, Figure Vent Hood

SECTION 2

INSTALLATION

V. VENTILATION GUIDELINES

A mechanically driven ventilation system is required for the PS200-R68 Series Middleby Marshall conveyorized gas ovens. The minimum hood canopy dimensions are outlined below.

Local codes and conditions vary greatly from one area to another and must be complied with. These are the “Authority having jurisdiction” as stated by the National Fire Protection Association, Inc. in NFPA 96-latest edi- tion. Following are the suggested requirements for good ventilation. Please remember these are general recom- mendations or guidelines, you may have a special con- dition or problem that will require the services of a ventilation engineer or specialist. Proper ventilation is the oven owner’s responsibility. Improper ventilation can inhibit oven performance. It is recommended that the ventilation and duct work be checked every three months.

Grease filters in the intake of the hood may be required by local codes.

VENTILATION HOOD

The rate of air flow exhausted through the ventilation system is generally between 1400 and 2500 CFM, but may vary depending on the oven configuration and hood design. To avoid a negative pressure condition in the kitchen area, return air must be brought back to replenish the air that was exhausted. A negative pressure in the kitchen can cause heat related problems to the oven components as if there were no ventilation at all. The best method of supplying return air is through the heating, ventilation and air conditioning system (HVAC). Through the HVAC system, the air can be temperature controlled

for summer and winter. Return air can be brought in directly from outside the building, but detrimental affects can result from either extreme seasonal hot and cold temperature from the outdoors.

NOTE: Return air from fan driven system within the hood must not blow at opening of bake chamber or poor oven baking performance will result.

VENTILATION CAPTURE TEST

It is recommended that a 30 second smoke candle test be performed on your ventilation hood system. Follow the steps below to complete the ventilation smoke test.

All tests are to be done on single ovens or lower units of a double oven. We recommend you wear protective gloves when performing this test. At no time should food be present when the smoke test is being conducted. Also check that no fire suppression system will be activated by the smoke.

1.Turn ventilation system on.

2.Turn oven(s) on and allow to heat up to customers normal operating temperature, or a minimum of 480°F (248°C).

3.Turn conveyor off. Place a 30 second smoke candle in a pie or cake pan which is no higher than 3" (76mm).

4.Open the front oven window. Next, light the smoke candle in the pan and then slide the pan into the center of the bake chamber on the conveyor belt and close the window.

5.The ventilation hood should capture 90% to 100% of the smoke produced by the candle.

	2”
	51mm
	minimum to
	allow stacking
	of ovens
10”		8”	3”
	17-1/2”	203mm
254mm
			76mm
	445mm

Figure 2-10

Vent Hood

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