Thermal analysis & ovens
Muffle Furnace
An electrically heated, insulated chamber that reaches several hundred to over 1000 °C. In QC it is used to ignite samples for sulphated ash (residue on ignition) and to bring crucibles to constant mass.
- Pharmaceutical
- Food
- Cement and ceramics
- Mining
- Environmental
TROUBLESHOOTING
Common problems, causes and fixes
Slow to reach set point
Likely causes
- • Ageing heating element
- • Door seal damaged
- • Supply voltage low
What to do
- • Have elements checked and replaced
- • Replace the seal
- • Check the electrical supply
Temperature overshoots
Likely causes
- • Controller tuning poor
- • Thermocouple loose or moved
What to do
- • Re-tune the PID controller
- • Refit the thermocouple
Display differs from reference thermocouple
Likely causes
- • Controller thermocouple drifted
- • Probe placed in a cooler zone
What to do
- • Calibrate or replace the thermocouple
- • Measure in the working zone
Sulphated ash results variable
Likely causes
- • Crucibles placed near the door
- • Cooling time not controlled
- • Incomplete charring
What to do
- • Use the central working zone
- • Use a fixed desiccator cooling time
- • Char completely before ignition
In LimsPulse · Calibration Management
Keep every Muffle furnace in control: usage logs, calibration and maintenance schedules, and automatic blocking of overdue instruments.