GE PT920 Technical Service Manual

Also see for Profile PT920: Installation instructions Installation instructions Installation instructions Brochure Installation instructions

GE PT920 Technical Service Manual Manual pdf 29 page image

– 29 –Thermal SwitchesLimit Thermal SwitchThe high limit thermal switch is wired in series withthe common side of all the elements, which are tiedto the common side of the double line bake relay.This limit switch opens at 284°F and closes when thetemperature cools below 254°F. This switch is usedto protect against element runaway. The symptomof this switch being tripped is the elements will notwork for any operation.To remove the limit thermal switch:The high limit thermal switch is located on the backside of the wall oven (See Component Locator Views).Remove the wall oven from installation. (See1.Oven Removal.)Remove the appropriate rear access panel.2.Disconnect wires, remove two 1/4-in. hex-head3.screws and the thermal switch.Thermal SwitchLow Voltage High Temperature Thermal SwitchThe clean FAD thermal switch is active during alloperations. If the thermal switch opens in any cookmode of operation, the fault code screen will show-F9- failure code. When this condition exists, checkthe fan operation (look for obstructions), inspectoven installation (make sure grille areas are notblocked), and oven insulation.The clean FAD thermal switch for single ovens orupper double ovens is mounted to the oven exhaustduct located in the component compartment infront of the fan motor. It is wired directly to the relayboard. This limit switch opens at 240°F and closeswhen the temperature cools below 190°F.Low Voltage Low Temperature Thermal SwitchThe bake FAD switch is active only during non-self-clean (unlock switch closed, lock switch open)operations.The bake FAD thermal switch for single ovens orupper double ovens is located under the rear topcover in front of the cooling fan. It is wired in serieswith the unlock motor switch.The bake FAD thermal switch for lower double ovensis located in the lower oven control compartment. Itis wired in series with the unlock motor switch.The values for these thermal switches are:OPEN CLOSESingle Oven 205°F 177°FDouble Upper 205°F 177°FDouble Lower 240°F 190°FNote: The following is an indication of an openbake FAD: A cooking mode is selected. When STARTis pushed, the status screen displays "DONE" thenreverts back to the home menu. The lock motorcontinues to run while seeking the "Unlocked"position.Note: To remove the clean FAD thermal switch onlower double ovens see the lower oven section ofRelay and Power Boards.To remove the clean FAD thermal switch on singleand upper double ovens:Access the control compartment. (See1. AccessControl Compartment.)Remove two 1/4-in. hex-head screws and the2.thermal switch.Disconnect the 2 wires from the thermal switch.3.Limit Thermal SwitchThe lower double oven clean FAD thermal switch isriveted to the lower oven vent trim. It opens at 250°Fand closes when the temperature cools below 220°F.(Continued Next Page)Note: The following is an indication of an openclean FAD: A cooking mode is selected. When STARTis pushed, the control displays “F9 – FAD ERRORDETECTED – MODE CANCELED” then returns tohome.