# Discover the Ideal Thermistor for Water-Cooled PCs in 2023

For water-cooled PCs, the type of thermistor used is a 10k ohm NTC (Negative Temperature Coefficient) thermistor. This type of thermistor is widely used in PC water cooling due to its precision and compatibility with various control systems.

## Understanding NTC Thermistors

NTC thermistors are a type of resistor that exhibits a decrease in resistance as temperature increases. This inverse relationship between resistance and temperature is known as the Negative Temperature Coefficient (NTC) effect.

The resistance of an NTC thermistor can be described by the Steinhart-Hart equation:

``````R = A * exp(B / (T + C))
``````

Where:
– R is the resistance of the thermistor in ohms (Ω)
– T is the absolute temperature in Kelvin (K)
– A, B, and C are constants specific to the thermistor material and construction

Typical values for a 10k ohm NTC thermistor at 25°C (298.15K) are:
– A = 1.0128 × 10^-3
– B = 2.372 × 10^3
– C = 1.0

This equation allows for accurate conversion between the measured resistance and the corresponding temperature.

## Advantages of NTC Thermistors for Water Cooling

1. Precision: NTC thermistors offer high accuracy and sensitivity, typically with a tolerance of ±1% or better. This allows for precise temperature monitoring in water cooling systems.

2. Wide Temperature Range: NTC thermistors can operate over a wide temperature range, typically from -40°C to 125°C, making them suitable for a variety of water cooling applications.

3. Fast Response Time: NTC thermistors have a fast response time, allowing them to quickly detect changes in water temperature, which is crucial for effective cooling control.

4. Compatibility with Control Systems: NTC thermistors can be easily integrated with various control systems, such as microcontrollers (e.g., Arduino) or dedicated water cooling controllers, enabling advanced temperature monitoring and fan control.

5. Cost-Effectiveness: NTC thermistors are generally inexpensive, making them a practical choice for DIY and budget-conscious water cooling setups.

## Integrating NTC Thermistors into Water Cooling Loops

NTC thermistors are often integrated into G1/4 fittings, which are the standard size for water cooling components. This allows for easy installation into the water cooling loop, as the thermistor can be placed directly in the water flow.

Common placement locations for NTC thermistors in a water cooling loop include:

1. Inlet of the Radiator: Measuring the temperature of the water entering the radiator can provide insights into the overall system performance and help optimize fan speeds.

2. Outlet of the Radiator: Monitoring the temperature of the water leaving the radiator can help assess the cooling capacity and identify any potential issues.

3. CPU Block Inlet/Outlet: Measuring the temperature at the CPU block’s inlet and outlet can help evaluate the cooling efficiency of the CPU block and the overall system.

4. Reservoir: Placing a thermistor in the reservoir can provide a good representation of the average water temperature in the system.

By strategically placing NTC thermistors at various points in the water cooling loop, users can gather comprehensive temperature data, which can be used to optimize fan speeds, monitor system health, and ensure efficient cooling performance.

## Connecting NTC Thermistors to Control Systems

For DIY water cooling projects, NTC thermistors can be easily connected to microcontroller boards, such as Arduino, to enable temperature monitoring and fan control.

The process typically involves the following steps:

1. Wiring the Thermistor: Connect one end of the NTC thermistor to the analog input pin of the microcontroller and the other end to the ground (GND) pin.

2. Resistance Measurement: The microcontroller can read the resistance value of the thermistor by applying a known voltage and measuring the resulting voltage drop across the thermistor.

3. Temperature Calculation: Using the Steinhart-Hart equation or a pre-calculated lookup table, the microcontroller can convert the measured resistance to the corresponding water temperature.

4. Fan Control: Based on the measured temperature, the microcontroller can adjust the fan speeds to maintain the desired water temperature and optimize cooling performance.

Many Arduino libraries, such as the “NTC Thermistor” library, provide pre-built functions to simplify the process of reading the thermistor and converting the resistance to temperature. This makes it easier for DIY enthusiasts to integrate NTC thermistors into their water cooling projects.

## Conclusion

In summary, the type of thermistor used for water-cooled PCs is a 10k ohm NTC (Negative Temperature Coefficient) thermistor. These thermistors offer precise temperature measurement, fast response times, and compatibility with various control systems, making them a popular choice for both DIY and commercial water cooling solutions. By strategically placing NTC thermistors in the water cooling loop and integrating them with microcontrollers, users can optimize cooling performance, monitor system health, and ensure the longevity of their water-cooled PC.