82 1100 Series FD Reference Manual
4 Troubleshooting and Test Functions
Leak
A leak was detected in the detector.
The signals from the two temperature sensors (leak sensor and 
board-mounted temperature-compensation sensor) are used by the leak 
algorithm to determine whether a leak is present. When a leak occurs, the leak 
sensor is cooled by the solvent. This changes the resistance of the leak sensor 
which is sensed by the leak-sensor circuit on the FLM board.
Probable Causes
• Loose fittings.
• Broken capillary.
• Leaking flow cell.
Suggested Actions
✔ Ensure all fittings are tight.
✔ Exchange defective capillaries.
✔ Exchange flow cell.
formation
Detector leak error may be caused by the Agilent 1100 sampler. In each 
sampler injection sequence, step# 2 ejects the mobile phase stored in the 
metering head during the previous injection. This  mobile phase is ejected 
through the short plastic tube connected to port# 4 of the sampler switching 
valve. The output of port# 4 is integrated into the sampler's contingency leak 
drain system, which eventually terminates in the leak pan of the bottom 
module of the stack - the detector. With normal injection volumes and run 
times, the output of port# 4 is small, and evaporates right in the sampler leak 
pan. However, the output of port# 4 is significant, and a substantial volume of 
ejected mobile phase reaches the detector leak pan.