A cryosurgery system, comprising two or more cryoprobes is provided. Each cryoprobe includes a probe shaft having a distal section insertable in a patient and a proximal coupler. A connector interface with connection ports permits connections to a corresponding cryoprobe. Each connection port can have an isolating sleeve between the proximal coupler and the connection port when the proximal coupler of the respective cryoprobe is inserted in the connection port. The isolating sleeve can include an electrically insulating material so as to electrically isolate each cryoprobe connected to its corresponding connection port from other cryoprobes connected to their corresponding connection ports. An electrical measurement system can be connected to each connection port to detect electrical signals associated with the probe shaft. A control system can detect, based on the electrical signals detected by the electrical measurement system whether the probe shaft is electrically connected to the electrical heater.