Ecobee ecobee3 Lite Smart Thermostat HIGH-TEMP Error Fix: High Temperature Alert

Error code HIGH-TEMP on the Ecobee ecobee3 Lite Smart Thermostat means: High Temperature Alert. Home temperature exceeded the configured high temperature threshold — check that the cooling system is running, thermostat is calling for cool, and the AC compressor and indoor fan are operating; verify windows and doors are closed

The most successful fix is "Test and Repair AC Compressor and Indoor Fan Circuit" (hard difficulty, ~60 minutes). Estimated DIY cost: $10-$20. HomeMD has 2 community-ranked fixes for this error.

This error is rated medium severity. It should be addressed soon, but your appliance may still function in a limited capacity.

Yes — the top-ranked community fix ("Test and Repair AC Compressor and Indoor Fan Circuit") is rated hard difficulty and takes about 60 minutes. Tools needed: T20 Torx screwdriver, Multimeter, Capacitor tester.

DIY cost: $10-$20. Professional repair typically costs $150-$250. Many homeowners save money by trying the top-ranked community fix first.

The Ecobee ecobee3 Lite Smart Thermostat has 8 other known error codes, including: APP-SYNC (App and Thermostat Out of Sync), AUX-OUTDOOR (Auxiliary Heat Outdoor Temperature Alert), AUX-RUNTIME (Auxiliary Heat Runtime Alert), BLOWN-FUSE (HVAC Control Board Fuse Blown), COOL-FAIL (Cool Not Reaching Set Temperature), and 3 more.

Error code HIGH-TEMP also appears on 5 other Ecobee models: ecobee Smart Thermostat Enhanced with Radar Occupancy Sensor and Large Touchscreen, ecobee Smart Thermostat Essential with Touchscreen Display and eco+ Smart Features, ecobee Smart Thermostat Premium with Siri and Alexa Built-In, Air Quality Monitor, and SmartSensor Included, ecobee SmartThermostat with Voice Control and Alexa Built-In, ecobee4 Smart Thermostat. The fix may vary by model, so check each model's specific page for tailored repair steps.