Fix Wrong Temperature & Humidity Sensor Readings
By Ceiling Fans, Home Store for Light Fixtures | Published: 2026-10-21
Category: How-to Guides
Learn why your temperature humidity sensor shows wrong readings and how to fix common issues with placement, calibration, and connectivity.
Quick answer
Most inaccurate readings from a temperature humidity sensor come from poor placement, interference from nearby electronics, or a weak Zigbee connection. Check the sensor location first, then verify calibration and network signal.
Why placement matters more than you think
A sensor placed in direct sunlight, near a window, or close to an air vent will report skewed temperature and humidity. The LCD screen on models like the SONOFF Zigbee LCD Display Smart Temperature Humidity Sensor makes it easy to spot these errors in real time, but the fix is simply moving the sensor to a shaded, interior wall away from drafts and heat sources.
Bathrooms and kitchens are notorious for false humidity spikes. If your sensor is in one of these rooms, expect temporary high readings after a shower or cooking. That is normal behavior, not a defect.
Zigbee signal strength can cause intermittent errors
A weak or unstable Zigbee connection can cause the sensor to report outdated values or fail to update. This is especially common if the sensor is far from the coordinator or behind thick walls. The SONOFF sensor uses Zigbee 3.0, which has good range, but obstacles still matter.
Check the signal strength in your smart home app. If it shows low, add a Zigbee repeater (like a smart plug) between the sensor and the hub.
Calibration is rarely needed but worth checking
Most modern sensors are factory-calibrated, but drift can occur over time. You can compare your sensor's reading against a known-accurate reference (like a sling psychrometer or a second sensor placed side-by-side). If the difference is consistent, some smart home systems allow you to apply an offset. The SONOFF sensor does not have a user-facing calibration adjustment, so if drift is significant, consider replacing the unit.
Diagnosis steps
- Symptom: The temperature or humidity reading is clearly wrong compared to how the room feels or to another sensor. For example, showing 80% humidity in a dry living room.
- Likely cause: Sensor is in direct sunlight, near a heat source, close to a draft (window, vent, door), or in a high-humidity zone like a bathroom. Alternatively, the Zigbee signal is too weak, causing stale data.
- Corrective action: Move the sensor to an interior wall, away from windows, vents, electronics, and direct sun. Ensure it is at least 1.5 meters off the floor for representative readings. If the issue persists, check the Zigbee signal in your app and add a repeater if needed.
- When to stop or choose another option: If the sensor still shows incorrect readings after repositioning and verifying a strong Zigbee signal, the unit may be defective. Consider replacing it rather than continuing to troubleshoot. If you have a second sensor, place it next to the suspect one for a side-by-side comparison before buying a replacement.
Product facts
- SONOFF Zigbee LCD Display Smart Temperature Humidity Sensor: The SONOFF Zigbee LCD Display Smart Temperature Humidity Sensor provides real-time readings on its LCD screen and can store and export historical data via the app. The LCD display lets you instantly see if the reading looks off, and the historical data helps you spot patterns that reveal placement or connection issues.
SONOFF Zigbee LCD Display Smart Temperature Humidity Sensor
