Lochinvar ARMOR 150 - 800 - Manual (Page 23)

3
Troubleshooting
Service Manual
23
3
Troubleshooting
(continued)
Table 3B - Inlet/Outlet System Sensor Resistance vs. Temperature
Temperature °F Resistance
Ω
Temperature °F Resistance
Ω
50 18,780 158 1,990
68 12,263 176 1,458
86 8,194 194 1,084
104 5,592 212 817
122 3,893 -- --
140 2,760 -- --
Table 3C - Flue Temperature Sensor Resistance vs. Temperature
Temperature °F Resistance
Ω
Temperature °F Resistance
Ω
68 14,773 176 1,707
86 9,804 194 1,266
104 6,652 212 952
122 4,607 230 726
140 3,252 248 560
158 2,337 -- --
Checking temperature sensors
The water heater temperature sensors (inlet water, outlet water, system water, and flue) are all resistance type devices. The
following tables show the correct values for the sensors at various temperatures. Use an ohmmeter to read the resistance of the
sensor at a known temperature. If the resistance of the sensor does not closely match its corresponding table, replace the sensor.