Hello, welcome to my first blog!

I have the opportunity to experiment with a new product, Avnet's Renesas ZMOD4410 Indoor Air Quality HAT for the Raspberry Pi (thank you Avnet and Element 14!). The HAT provides an easy to use Raspberry Pi evaluation and development platform for the pre-calibrated Renasas ZMOD4410 sensor. The ZMOD4410 monitors Total Volatile Organic Compounds (TVOC), measures Indoor Air Quality (IAQ) and estimates carbon dioxide (eCO2) levels - all useful to determine if air quality is good or bad. Additionally, the Avnet HAT incorporates a HS3001 Relative Humidity (RH) and temperature sensor to provide additional helpful data.  

The Avent ZMOD4410 IAQ Hat has been set to monitor various locations in our home; bedrooms, bathrooms, and garage. Presently it is in one of the bedrooms. There's been lots of excitement and participation from my family too!


This road-test had two options; basic or advanced. The basic review is an evaluation of the HAT using available demonstration software. An advanced review may involve developing an application for the HAT while leveraging the proprietary documentation and ZMOD algorithm libraries available through Renesas subject to conditions and terms. I chose to conduct a basic evaluation of the HAT using the demonstration software.



In addition to the Avnet ZMOD4410 Indoor Air Quality Hat, I was happy to see that Element 14 included a new Raspberry Pi 3 B. This helps get this show on the road quickly. Both arrived in great condition with a sheet of packing paper providing necessary cushion. Within the road-test package, I was expecting a micro SD card to be included however, this was not to be, there was no SD card. The shipping box seemed to have experienced a thorough customs inspection and arrived a little rough which may offer a possible explanation. No matter, I had a spare micro SD card and was not going to let this hold me up. 


Installing the Avnet Renesas ZMOD4410 Indoor Air Quality HAT onto the Raspberry Pi 3 was straight forward. The included male-female 40 pin header makes the connection easy. Be careful not to stab your thumbs when pushing the pins through the HAT's header, like I did. For those developing low power applications, the provided jumper can be soldered to the board to enable the user-adjustable power supply.

I assembled the Pi and TVOC Sensor HAT into an extra Raspberry Pi 3 case that I had. I left the top off to ensure the sensors were adequately exposed to the surrounding air. Also the lid would have required modification to fit the HAT.


Setup and installation

The Avnet Renesas ZMOD4410 Indoor Air Quality HAT documentation is provided on their site. Installing the software is relatively simple however, there is very little documentation to help you get started with the test application. The application will not run 'out of the box' with a standard Raspberry Pi OS installation until you complete additional steps* to allow the board to communicate with Python. Renesas technical support staff were very helpful to outline the required settings but declined to answer further questions, clarifying that support is available only to corporate customers. Support requests for the Indoor Air Quality HAT should be directed to Avnet.

With a blank micro SD card, I started from scratch to install a new Raspberry Pi OS installation and get the software running:


  1. Install Raspberry Pi OS (32-bit) using the Raspberry Pi Imager
  2. When first booting the Raspberry Pi, the Pi will ask for initial setup information and network settings. The Pi should update and restart.
  3. *Enable I2C communication on the Raspberry Pi. Go to Preferences, Raspberry Pi Configuration, Interfaces, I2C enable 
  4. While you are in the interfaces setup screen, you can also enable VNC if you would like to remotely manage the Raspberry Pi using a VNC viewer. I found this to be very helpful. 
  5. *Enable the Pi GPIO library to run as a daemon. Open a terminal window, and enter the following command
    • sudo systemctl enable pigpiod.service
  6. Reboot the Pi
  7. Download and open the test/validation application. Unpack the files somewhere appropriate, such as your home directory.
  8. Start the software by running start.sh, click on start sensor, choose a log file and voila!



Now that the application is up and running, testing is well underway for the review. I will be conducting measurements and evaluations of total organic compound concentrations, air quality and eCO2 in the following locations:


1) Office

As a designated critical service of the government, my department and staff work primarily from the office while others are at home. I have little to no control over the air quality in my work environment, however if there is a problem, I can use data to get remediation activities underway. I have long suspected the air quality at my office is not great but have had little to present to the responsible department in terms of evidence. Concerns about air quality are amplified by the current pandemic.


2) Home - Common Areas

Air quality in our home is the primary concern. With pets, kids and many activities, quality of the air is a key focus area in our home. This test would provide data for the common areas such as living rooms, kitchen, basement and furnace room


3) Home – Daughters Bedroom (aka lizard den)

I am calling out some areas in the house separately. Most importantly is the bedroom of my young adult daughter, in which she keeps her pets and bugs. She presently has 15 geckos and snakes in tanks and 100’s of bugs that she breeds for sale and as food for the reptiles. One of the geckos has recently become a new mom, and she has two new arrivals.


This room did not smell awesome, so I had asked her to purchase an air purifier. That helped a lot. However, I remain concerned that she may be putting her health at risk with so many creatures in a small space. IAQ data may support her claim or the data may help her realize that the situation needs to be addressed, perhaps she would agree to reduce the number of creatures? Tests would be conducted with and without the air purifier running. Both odor and air quality are key for this room.


4) Home - Garage

An evaluation of the home would not be complete without tests being conducted in the attached garage. While I have no specific concerns in that space, it does have it’s own furnace and vehicles, and can easily be a source of poor quality air. One of my workbenches is located in the garage.


5) Home – Washrooms

The Avnet Renesas ZMOD4410 Indoor Air Quality HAT has the ability to detect changes in odors, in particular sulfur. This capability demands tests to be conducted within the washrooms in the home. The results may be embarrassing!


Review:  Please read my full review here IDT ZMOD4410 Indoor Air Quality Raspberry Pi HA... | element14 | RoadTests & Reviews


Thank you and I look forward to hearing your comments on my blog!