550 and 551 Temperature Controllers

Fenwal 55 Temperature Controller Repair Services

Professional Repair Solutions for Fenwal Model 55 Controllers

When your Fenwal 55 temperature controller malfunctions, critical process control is compromised, leading to product quality issues and costly production delays. Control System Labs provides expert repair services for these legacy industrial temperature regulation devices.

Typical Fenwal 55 Controller Failures

Our experienced technicians routinely diagnose and repair common failure modes in these analog temperature controllers:

- Thermocouple input amplifier drift causing inaccurate temperature readings

- Relay output contact welding or coil burnout preventing proper switching operation

- Potentiometer wiper wear resulting in erratic setpoint adjustment

- Power transformer secondary winding breakdown causing voltage regulation issues

- Internal calibration circuit component aging leading to control loop instability

Comprehensive Repair Methodology

Each Fenwal 55 controller receives thorough evaluation using precision calibration equipment and thermal simulation chambers. Our repair process includes:

- Complete circuit board inspection and component testing

- Thermocouple input linearization circuit verification

- PID control algorithm parameter validation

- Output relay contact resistance measurement and replacement

- Temperature display accuracy calibration

- Extended operational testing across full temperature range

Rigorous Testing Protocol

Following repair completion, units undergo comprehensive burn-in testing including thermal cycling, setpoint accuracy verification, and alarm function validation. Each controller is calibrated to original factory specifications ensuring precise temperature regulation upon return to service.

Minimize process disruption with reliable Fenwal 55 temperature controller repairs. Contact Control System Labs for fast turnaround service that restores critical temperature control functionality while extending equipment operational life through professional component-level restoration.