Vaillant Ntc Sensor 19-3592 Ch Flow / Return

Vaillant Ntc Sensor 19-3592 Ch Flow / Return

The Vaillant NTC Sensor (Part No. 19-3592) is a high-precision thermistor responsible for monitoring the temperature of the water as it leaves (Flow) and enters (Return) the boiler. This "Negative Temperature Coefficient" sensor works by decreasing its electrical resistance as the water temperature rises. The boiler's PCB uses these constant readings to modulate the burner flame, ensuring the system reaches the desired temperature efficiently while preventing dangerous overheating.

This part is also commonly listed under the updated part number 193592.

Key Features and Specifications
Dual Functionality: In most Vaillant ecoTEC models, this same sensor is used for both the flow and return pipes. It is a "clip-on" design, allowing it to be securely attached to the external surface of the copper pipework.

Precise Modulation: By monitoring the temperature differential between the flow and return (the "Delta T"), the sensor allows the boiler to modulate its output, significantly reducing fuel consumption.

Genuine Vaillant Part: Manufactured to strict OEM standards to ensure the resistance curve perfectly matches the requirements of the Vaillant control board.

Durable Construction: Built with heat-resistant polymers and high-conductivity contact plates to ensure accurate readings even after years of constant thermal cycling.

Safety First: Acts as a primary safety limit; if the sensor detects an abnormal temperature spike, it will trigger a lockout (often fault code F.20) to protect the heat exchanger.

Boiler Compatibility
This NTC sensor is one of the most widely used spares in the Vaillant range, fitting over 90 different models. Common compatible appliances include:

ecoTEC Plus (Combi, System & OV): 412, 415, 418, 424, 428, 430, 438, 612, 615, 618, 624, 630, 637, 824, 831, 837, 937.

ecoTEC Pro: 24, 28, 30.

ecoTEC Exclusive: 832, 838.

ecoFIT Pure: 412, 415, 418, 425, 430, 435, 612, 615, 618, 625, 630, 825, 830, 835.

Technical Tip: Common Vaillant fault codes associated with a failing or disconnected NTC sensor include F.20 (Overheating), F.71 (Flow sensor signal constant), and F.72 (Flow/Return sensor permanent temperature difference).

Maintenance and Installation Advice
NTC sensors are "dry" sensors, meaning they clip onto the outside of the pipe and do not require the system to be drained for replacement. However, for an accurate reading, it is essential that the contact surface of the pipe is clean and free of corrosion. Many engineers apply a small amount of heat-conductive silicone paste between the sensor and the pipe to ensure maximum thermal transfer.

Essential Companion Products
When diagnosing temperature or circulation issues, the following parts are frequently checked alongside the NTC sensors:

Direct Product Link: Vaillant NTC Sensor - 19-3592

Water Pressure Monitoring: Vaillant Sensor - 0020059717

Air Removal: Vaillant Automatic Air Vent - 0010033857

System Protection: Fernox F1 Central Heating Protector (to prevent debris buildup that affects circulation).

Specialist Support and Local Collection
Is your boiler displaying a temperature fault or cycling on and off too frequently? Our trade counter team can help you verify the resistance values for this sensor to confirm if it needs replacing.

Visit our trade counter and Bathroom Showroom at 61 Fullers Road, E18 2QB for expert technical advice and immediate access to genuine Vaillant spares.