Z-Wave Stick & Home Assistant: Troubleshooting and Support

Home Assistant is a powerful, open-source platform designed for home automation enthusiasts who enjoy full control over their setups. Its flexibility and customization options make it a favorite among advanced users, but it also requires a significant level of technical expertise to configure and manage.

The Z-Wave Stick: What It Is and What It Isn’t

At its core, a Z-Wave stick is a simple piece of hardware equipped with a Z-Wave chip that acts as a radio transmitter. This device enables communication between your computer or hub and your Z-Wave devices, serving as a bridge for transmitting and receiving commands within your smart home network.

However, it’s essential to understand that compatibility and functionality are determined by the home automation software you choose, such as Home Assistant. The Z-Wave stick itself doesn’t influence these aspects—it simply provides the necessary hardware interface (Z-Wave radio) to facilitate communication. The real magic of device compatibility, automation, and control lies entirely in the software's ability to interpret and manage these transmissions effectively.

Why Home Assistant Requires Advanced Skills

Home Assistant’s open-source nature means that support is provided by the community rather than a professional customer service team. Here are some resources recommended by Home Assistant to help you troubleshoot and report issues with your system:

Community Forums: A wealth of user-generated advice and troubleshooting tips.
Documentation: Covers beginner to advanced topics around the installation, setup, configuration, and usage of Home Assistant.
GitHub: A platform for reporting issues and finding software updates.
Discord: Real-time support from the developers and the user community.

For those new to Home Assistant, diving into these resources is crucial. The platform’s complexity can be overwhelming, but for experienced users, it offers unparalleled flexibility and control, empowering them to create deeply customized automations and integrate devices across multiple ecosystems seamlessly.

OTW Firwmare Updates

Note that the ZST39 800 Z-Wave stick is intended for expert Z-Wave users only that are comfortable with at least basic programming and have plenty of experience with Z-Wave technology. Do NOT update your Z-Wave stick unless absolutely needed. This is a static controller with a crucial function to your network. Only perform the update when you're 100% confident you have the right environment including the correct firmware file. If power is interrupted at any point during the update, the device will be bricked.

While the 7.19 SDK released by Silicon Labs earlier this year can indeed sometimes produce controller lock-up issues, this has only been present in edge cases. If you're not experiencing any issues with your network or controller, you can ignore the warning on Home Assistant and there's no need to update the firmware. It's recommended that the module is treated like bios in your computer and updated only if absolutely necessary to avoid service crashes. It's also very important that there are no power interruptions to the device during the update.

Since Home Assistant is not a Z-Wave certified software, and since we have seen many issues with the OTW process on Home Assistant, it is always recommended to use Simplicity Studio's PC Controller software to perform the OTW updates. We cover that in detail here as well.

NVM Backup

The process for backing up the Non-Volatile Memory (NVM) of a Z-Wave stick depends on the open-source software you are using. Since the Z-Wave stick can be paired with various platforms such as PC Controller, Home Assistant, HomeSeer, openHAB, and ISY, the backup and restoration steps will vary based on the specific software.

You can use the PC controller's built-in back up tool to perform an NVM backup for the stick as long as you are restoring to the same version, which allows you to back up all settings on the hard drive or any other location and then retrieve it using the same method. This only works when backing up the same version you are restoring it to (800 > 800 or 700 > 700).

The reason we do not provide hub specific steps for backing up a different version and restoring it to the 800 series is because the 800 series has a different NVM memory layout than the earlier 700 series. The 700 series NVM is 48 KB divided into two sections, one for the Z-Wave protocol related data (nodes, routes, etc.), one for the application related data (radio settings, etc.), while the 800 series NVM is only 40 KB, and application and protocol data is stored together in a single section.

PC controller does not care about this distinction and just writes the raw NVM data. If you restore an 700 series NVM onto an 800 series controller with PC controller, you end up with an incorrect layout, which the 800 series firmware cannot read, and 8 KB of missing data.
We have received feedback, but not instructions, that Z-Wave JS (UI) detects the NVM layout of the target controller first, and if that layout is supported, it will parse the source NVM and rewrite it into the new target format.
A lot of users have used Z-Wave JS's NVM backup/restore to migrate from older sticks to ZST39-800, since it's currently the only way to do this migration without having to re-pair all devices according to the Z-Wave JS team.
We do not have specific instructions, but this thread in the community forum is helpful. You need to be using the Z-Wave JS UI in order to complete it.

The NVM backup and restoration process is entirely dependent on the software it is paired with. Due to the variety of backup processes on the various systems—most of which are not documented by open-source software developers—we do not provide NVM backup and restoration instructions for the stick at this time outside of the PC Controller instructions for backing up and restoring the same chip version. We encourage users to provide feedback to their open-source software developers regarding the availability of documentation on the open-source platform you are using.

We strive to offer comprehensive documentation for our devices to ensure a smooth user experience. However, with the wide range of hubs and software available—many of which are open-source and continuously evolving—it can be challenging to maintain up-to-date instructions for third-party software. Since open-source platforms do not always provide official guides, creating instructions for software we do not develop places a strain on our resources.

For the most accurate and up-to-date information, we recommend consulting the support channels and official documentation of the specific software you are using. Most proprietary hubs, such as Z-Box or Hubitat, offer built-in backup and restoration tools with clear instructions provided by their manufacturers; this is not the case at this time with open-source channels.

Regarding Home Assistant, there are currently no official guidelines on NVM backup and restoration. Once Home Assistant releases official documentation, we will be happy to share that information. In the meantime, we recommend checking Home Assistant’s documentation and community forums for the latest updates and guidance.

Our Support Commitment

You can always count on hardware support for the Z-Wave stick from the Zooz support team. If the stick is recognized on your computer or via tools like Silicon Labs' Simplicity Studios PC Controller software, it confirms that the hardware is functional. Anything beyond this is outside the scope of our support team.

Here are examples of issues we assist with:

Verifying Stick Functionality: Ensuring the stick is recognized on your computer or with PC Controller software.
Troubleshooting Basic Hardware Issues: Addressing any defects or malfunctions with the stick itself.

Here are common challenges faced by new users that are best addressed in your home automation software's community:

Setup Issues: Integrating the Z-Wave stick with Home Assistant or other home automation software.
Custom Configurations or New Installations: Assisting with software-specific configurations.

While we are here to support you with stick hardware functionality and troubleshooting, integration and setup with home automation platforms like Home Assistant will be specific to your environment, including hardware and server details. With a DIY set-up including third party hardware and software, there are many factors that can cause issues. For these software-specific needs, we recommend utilizing the robust resources and communities provided by Home Assistant.

A Note on Firmware and SDK

The Z-Wave stick firmware is developed and maintained by Silicon Labs. They also provide the SDK software that powers the stick, ensuring compliance with Z-Wave standards and enabling communication with other Z-Wave devices. Zooz does not have the ability to modify or update this firmware, as it is proprietary to Silicon Labs. All updates, new features, or enhancements to the firmware and SDK are entirely managed by Silicon Labs, ensuring consistency and reliability across the ecosystem.

For those seeking a powerful, customizable home automation solution, Home Assistant combined with our Z-Wave stick is a fantastic option—but it’s best suited for users who are ready to take on the challenge of advanced configuration and self-guided troubleshooting.