If you’re troubleshooting your old Intellitec system or plan on using the original thermistors (thermal resistor) with a new Waiter ECC, its a good idea to verify that the thermistors are operating OK.
Most Fleetwoods that use the Intellitec controller have two temperature sensors, one in the rear bedroom area and one in the kitchen area, usually on the underside of a kitchen cabinet. These are connected to the Intellitec thermostat controller. These sensors are generally accurate and seldom break.
They can be tested using a regular ohmmeter to read their resistance.
Before disconnecting the plugs from the Intellitec Operator control panel, take a picture so you know what connector went to what plug. Using an ohmmeter, measure the resistance of the two leads of the connector. At room temperature (77 deg F) the resistance should be right at 10,000 ohms. If its cooler or warmer, you can use the chart to see what the resistance should be for any given temperature. CLICK HERE to download the temperature to resistance chart.
As you study the chart, you’ll see that the resistance of the thermistors changes fairly significantly as the temperature changes.
IMPORTANT NOTE – If you’re installing the Waiter ECC, the two temperature sensor wire plugs no longer get plugged into the operators panel but are plugged into the control module. These four wires will need to be re-routed from the operator panel to the control module.