The Toyotomi Thermistor T-B OM-180, part number 20476773, is a replacement temperature sensing component used in select Toyotomi Toyostove oil-fired water heaters and furnaces to monitor internal temperature conditions. It provides critical feedback to the heater’s control system by converting temperature changes into an electrical signal that helps regulate burner operation and safety functions. This thermistor is manufactured to match original equipment specifications so it fits directly into the designated sensor location during service replacement when the existing thermistor is worn, inaccurate, or faulty.
This thermistor is intended for service or repair when temperature sensing issues are suspected in models requiring part 20476773, such as inaccurate temperature readings, improper cycling, or error indications on the control system. Accurate temperature feedback helps the control circuitry optimize combustion, manage system timing, and prevent overheat conditions. Installation should follow the model-specific service documentation to ensure the thermistor is positioned correctly in the temperature sensing well and securely connected to the control harness.
What’s Included: One (1) Toyotomi temperature sensing thermistor T-B OM-180.
Installation Limits: For replacement use only on compatible Toyotomi water heaters or heaters requiring the OM-180 thermistor; install with the heater powered off and confirm correct sensor placement per the service manual.
Compatibility: Compatible with Toyotomi models OM-180 and other appliances specified to use thermistor 20476773 for temperature sensing in the control system.
Oil Miser 180, Thermistor "T" "B" is located next to Heat Exchanger Assembly.
