601R51577-1 — Fan/ Sensor unit assembly Repair & Overhaul

Component Overview

A fan/sensor unit assembly is a combined component in the sensing and air management system that integrates a small aspirating or sampling fan with a temperature sensing element, drawing a representative air sample across the sensor so the control system reads accurate cabin or duct temperature with minimal lag. The fan ensures continuous airflow over the sensing element, improving response and accuracy of temperature feedback used for air conditioning control. Operating with continuous rotation and electrical excitation, common degradation includes motor bearing wear, increased vibration and noise, motor winding or brush deterioration, sensor element drift or open/short circuits, contamination of the air path reducing sampling flow, and connector and wiring fatigue. These conditions drive functional and resistance testing, fan rebuild, sensor calibration, and overhaul.

Aircraft Application

Part number 601R51577-1 (Fan/ Sensor unit assembly) is installed on the Bombardier CRJ700. QTC supports operators and MROs servicing this platform with certified repair and overhaul.

Our Repair Capability

QTC repairs and overhauls 601R51577-1 to the original manufacturer's specifications under our FAA and EASA Part 145 approvals. Our team — including former OEM sensors & switches engineers — performs teardown, inspection, cleaning, component replacement, functional testing, and certification, returning a serviceable unit with the appropriate airworthiness release. We also develop repairs for rejected and beyond-economic-repair (BER) hardware.

View Temperature Sensors & Switches capability →

Related Parts

Other fan/ sensor unit assembly part numbers we repair — view all Fan/ Sensor unit assembly parts →

Frequently Asked Questions