Where is the best place to mount outdoor sensor?

How much open air should I have above and below the sensor unit for optimal readings? The optimal location on my house has direct sun in the mornings (east side) - not sure if that matters.

Below the monitor should be at least 90cm to avoid dust from the ground impacting the measurements. Also if you can mount in in permanent shadow would be better as transient temperatures can also affect accuracy.

I love our AirGradient ONE Indoor Monitor Kit Version 9, installed in February 2024, using the MallocArray ESPHome HomeAssistant integration.

I’m ready to pull the trigger on the Open Air Kit, and assessing the best mounting location for it.

We’re in a single-story ranch house with 30" (0.75m) eaves so I can get it into a nice sheltered location. The distance from the eave to the ground is 9-1/2’ (3m). What is the optimal distance from the eave to the top of the unit?

We have a gas dryer vent outlet 10’ (~3m) away from our selected spot that exhausts 2’ (.5m) from the ground. Will that affect the readings?

Our gas furnace chimney is about 30’ (~9m) away and exhausts well above the peaked roof line, so that should not be a problem, right?

On a slightly different topic, the MallocArray integration has been great with Home Assistant. I see that Home Assistant integration is now supported natively. How does that compare with the MallocArray firmware, and are there other ESPhome alternatives?


I think the location you describe for mounting the monitor should be ok.

The only thing I am not 100% sure is the outlet from the gas dryer. However once you have the monitor, you can observe the readings during the operation of the dryer and check if you see any impact by it.

With the native home assistant implementation July release we will bring the same configuration options directly to HA that we have on the AirGradient dashboard.

I think @MallocArray ESPHome version might have a few additional features like different display styles but I’m sure he can give more details.

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Thanks, Achim. That makes sense. If I see readings impacted by the dryer outlet, I can move it to another spot.

Is there a minimum clearance between the top of the unit and the eave overhang? I want to be sure to provide the best airflow.

Great job on AirGradient! Thank you so much!

The native Home Assistant Integration brings all of the sensor data into HA from the stock Arduino based firmware, so you can use it right out of the box with no extra flashing. When the next version comes out that lets you change some controls on the device itself, the gap between the ESPHome firmware will be closed considerably. The stock firmware is also supported and maintained by the AirGradient team, instead of some random person on the internet. :wink:

The ESPHome firmware still has a few other advantages

  • Complete local control of the device and your data. No reliance on an external service (Next HA integration will also allow for local configuration control)
  • Disable CO2 Calibration if needed (Also planned for next HA Integration update)
  • Multiple LED bar configurations for ONE device. (Full bar for PM2.5, Full bar for CO2, Combo bar that shows PM2.5, CO2, and VOC at a glance)
  • LED fade option to make the outside of the LED bar be slightly dimmer (I think it looks slick)
  • LED config uses all LEDs and blends colors reflective of the sensor values, instead of jumps from green to yellow, or only a few yellow/green LEDs
  • Correction algorithms implemented on-device, instead of on AirGradient servers (Unclear at this time if the official firmware will make this available to HA Integration)
  • Uptime of device as a sensor
  • Options for AQI and NowCast values
  • Support for all AirGradient models, all the way back to the original DIY Basic

No minimum clearance on the top needed. It only needs unobstructed air flow at the bottom.


And thank you, @MallocArray, for the superb ESPHome integration! I didn’t know you were supporting all the models. I’ll probably try both, biased towards yours because I already use it on my indoor model. I really like the ComboLED and the display variations.

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