Turbo Chef Technologies NGC-1007 service manual Catalytic Converter, Removing the IR Element

IR ELEMENT AND CATALYTIC CONVERTER 51

The IR Element and Catalytic Converter provide two very different, but essential functions.

The IR element provides the bottom browning - similar to a residual broiler or salamander type cooking appliance - required for cooking most food items. The IR element temperature is independently controlled in each recipe.

The catalytic converter scrubs the air to eliminate VOCs and grease particulates that are liberated during the cooking process. It is important to properly care for the catalyst using only TurboChef® Oven Cleaner (P/N 103180 USA, 103380 Intl) and distilled water. For more detailed information, see the catalytic converter section below.

C O M P O N E N T S

IR Element

The IR element - a dual coil type heater - is located in the bottom of the oven cavity. The first coil is the heating coil. The second is the IR thermocouple wire. The heating coil outputs 3000 watts at 208 VAC. The heating coil’s resistance is 14.4 ohms at room temperature.

The thermocouple coil is a Type K thermocouple with a resistance of approximately 20 ohms at the splices located approximately 6 inches from the heater and 40 ohms measured at the extension wires at the I/O control board.

The IR element is controlled via the K5 solid state relay and the IR thermocouple via the I/O control board.

Catalytic Converter

The catalytic converter, a VOC type catalyst, is locat- ed behind the inside cook cavity wall and is responsi- ble for cleaning the recirculating airflow. The catalyst functions by substantially lowering the combustion temperature of grease entrained in the air path to approximately the same temperature

of the airflow, thus the grease burns and breaks down into CO2 and H2O as it passes through the catalytic converter. The catalyst will operate most efficiently at temperatures above 475ºF (246ºC).

The catalyst material is very sensitive to certain chemical compounds. Irreversible damage can occur if the catalyst is exposed to cleaning chemicals con- taining phosphates, NaOH, silicates, Na and Potassium Salts. These chemicals are found in most commercial degreasers and cleaners; therefore, only TurboChef® Oven Cleaner should be used.

C A U T I O N : Clean the catalytic converter with TurboChef ® Oven Cleaner and rinse

thoroughly with distilled water. Let the catalytic converter air dry before reinstalling. If TurboChef® Oven Cleaner is not available, do not use a substi- tute. Use distilled water only.

IR ELEMENT AND CATALYST REMOVAL

Refer to Figure 39 and the instructions below for removing the IR element and catalytic converter.

Removing the IR Element

1.Unplug the oven.

2.Disconnect the heater wires going to the EMI filter and the high-limit thermostat.

3.Locate where the IR element protrudes through the cook cavity walls and remove the snap rings (Item 116) using snap ring pliers. Retain snap rings (Item 116) and washers (Item 117). Figure 41.

4.Locate and remove the microwave shield (Item 119) by removing the four (4) #8 x 1/2” sheet metal screws (Item 120).

NOTE: Some models do not contain item 119.

5.Squeeze the IR element together inside the cook cavity and pull the IR element from the oven.