Sonda de temperatura Viessmann 7819967

NTC (Negative Temperature Coefficient) immersion temperature sensor from Viessmann. It is an important element of the gas boiler automation system, measuring the coolant temperature in the heating and hot water circuits and transmitting data to the control board to adjust the equipment operating mode. Unlike bimetallic relays, the NTC sensor provides smooth rather than discrete regulation, as its resistance changes inversely with water temperature. This allows the boiler to accurately maintain the set thermal regime and efficiently modulate the burner power. If your boiler has stopped responding adequately to temperature settings, does not heat water to the required level, or displays an error related to sensors, the problem may be a malfunction of this element. Technical specifications: Parameter Value Part numbers 7819967, 956.220.002. Manufacturer Viessmann (Turkey). Sensor type NTC immersion (thermistor) with negative temperature coefficient. Resistance (25°C) ~10 kOhm. Resistance (70°C) ~1.8 kOhm. Housing material Brass. Dimensions (L x W) 50 x 11 mm. Compatibility (Key point!) The 7819967 sensor is short and is installed in many modern Viessmann wall-mounted boilers, as well as in some indirect water heater models. Below is a list of main compatible series. This is not a complete list, so before ordering, be sure to check your boiler's manual or consult a specialist. Vitopend 100-W: WH1B, WH1D, WHO, WHE / WHEA. Vitopend 200-W: WHKA, WB2A, WS3A. Vitopend 222-W: WHSA. Vitodens 100-W: WB1B. Vitodens 200-W: WB2, WB2B, WB3. Vitodens 300-W / 333-W: WB3C, WS3A, WR3C, WS3C. Vitodens 343-F: WS4A. ⚙️ Signs of malfunction and need for replacement Malfunction