Thermostat emits a plastic or burning smell during operation

Safety: If you smell burning plastic or see smoke, immediately turn off the breaker and do not use the system until inspected.

Steps to address burning smell:

• 1. Identify source: Determine whether the smell comes from the thermostat, the Stelpro heater, or wiring/junction boxes.
• 2. Inspect thermostat: With power OFF, remove the thermostat and look for melted plastic, discoloration, or burnt components. If found, replace the thermostat.
• 3. Check terminals: Tighten all line and load terminal screws and inspect wire insulation for signs of overheating.
• 4. Inspect heater: Remove the heater cover (power OFF) and look for dust buildup or foreign objects touching the element. Clean thoroughly.
• 5. New heater burn-in: A slight odor is normal for a new Stelpro heater during the first few hours of operation. Ensure good ventilation and monitor closely.
• 6. Call a professional: If the smell persists or you see any signs of charring, contact a licensed electrician or Stelpro-authorized technician.

Warning: Do not ignore burning smells; they can indicate an imminent fire hazard.