Owner's manual

RFD1-42-2E Oven Owner’s Manual THEORY OF OPERATION

Version 1 15

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Damper slide

Damper Control

Figure 3. RFD1-42-2E Oven Damper Control.

3.2. Damper Control

The RFD1-42-2E oven comes with a manually adjustable damper mechanism which controls the

flow of fresh air into the chamber. The damper control is located on the left side of the oven

(Figure 3). The maximum amount of fresh air is distributed into the chamber when the damper is

in full open position. An additional adjustable damper is provided on the exhaust (Figure 4).

3.2.1. Determining Damper Settings

The optimum setting for the amount of fresh air that

should be distributed into the chamber depends on several

factors. These factors include ambient environment

temperature, load conditions, load distribution, heat-up

rates, cool-down rates, desired temperature uniformity

and, most importantly, the desired operating temperature.

Carefully consider existing engineering tradeoffs while

using guidelines to determine the fresh air damper setting.

In general, the damper should be set so that the amount of

fresh air flowing into the chamber agrees with the desired

operating temperature conditions. The following

paragraphs show the considerations involved with various

damper position settings.

3.2.1.1. Damper Full Closed Position

The chamber achieves maximum attainable heat-up rates when the fresh air damper lies in the full

closed position. With the damper in the full closed position, the chamber will operate at the

desired temperature using the minimum amount of power. In most cases, the oven also efficiently

operates at the chamber’s maximum operating temperature when in the full closed position.

3.2.1.2. Damper Full Open Position

The chamber operates at its minimum operating temperature with the fresh air damper in full

open position.

Friction heat from the air recirculation system builds up in the chamber. This causes chamber

temperature to rise slightly even without the heating system on. The chamber reaches thermal

equilibrium temperature after the recirculation motor runs for an extended period of time.

Notice

With the damper in full closed position, a predetermined amount of

fresh air enters the chamber via cutaways in the fresh air and exhaust

dampers. This amount of fresh air meets NFPA86 Safety Guidelines for

Class A ovens.