The Measuring head of our K-7400 and K-7400S osmometers are considered a wear part of the device. Therefore they cannot be repaired at KNAUER. If you think your measuring head may be affected and need advise, please contact support@knauer.net. If you are sure your measuring head is broken (e.g. the thermistor is obviously damaged), contact our sales team via sales@knauer.net and place an order for a replacement measuring head.