There are 2 different thermistor ESP probes for the Harman line; one has a black wire, one has a red wire. HHT 3-20-00844 Thermister Exhaust Sensing Probe | Post 2008 Harman Stove Replacement Part Harman Thermister/ESP Probe - Red Wires Harman Heatilator Red Esp Thermistor Probe 3-20-00844 1 This is a red ESP probe that is used on all newer pellet stoves post-2010. Some older models can use this part simply by switching the #5 DIP setting on the... Exhaust thermistor probe, ESP, Red Wire. Harman & Heatilator ESP Thermistor Probe Red Wire 3-20-00844 Fits Harman Pellet Stoves: ~ Absolute 43 ~ Absolute 63 ~ Allure 50 ~ Accentra Cast FS (Serial # 00840167 and higher) ~ Accentra Insert (Serial # 008241201 and higher) ~ Accentra 52i (All Models) ~ Accentra 52i-TC ~ Advance (Serial # 008360001 and higher) ~ P35I (All Models) ~ P43 (All Models) ~ P61 (Serial # 008085055 and higher) ~ P61A (Serial # 008085803 and higher) ~ P68 (Serial # 008280309 and higher) ~ PC45 (Serial # 008055031 and higher) ~ PF100 (Red Wires)
