Terms of service

These are the terms for using this site and the free tools it hosts, in plain language. By using serin-labs.com, you agree to them. Last updated September 4, 2026.

The store policies govern purchases and cover ordering, shipping, returns, and refunds, and the limited warranty covers hardware defects. This page covers the site, documentation, browser flash tool, and firmware.

Who we are

Serin Labs is an independent business based in New Jersey, United States. We are not affiliated with, endorsed by, or certified by Apple Inc., Mitsubishi Electric Corporation, or any other company named on this site. Their trademarks belong to them.

The site and its content

The guides, compatibility records, troubleshooting steps, and blog posts on this site are provided for informational purposes. We work to keep them accurate and current, but cannot guarantee that they are complete or error-free. They do not constitute professional HVAC or electrical advice. Model lineups and firmware change, and your indoor unit may differ from those we have tested.

Working on your HVAC equipment

Installing a controller requires opening the front panel of an indoor unit and connecting a cable to a service port. The Multi-Zone Controller connects instead at the outdoor unit or branch box, on the system's two-wire transmission connection. City Multi and P-series systems are often commercial equipment under a service contract, and a qualified technician should do that work. You accept the risks of working on your equipment, including the possibility that a third-party accessory may affect the manufacturer's warranty terms. Turn off power before starting. If you are not comfortable performing the work, hire a qualified HVAC technician. See safety and installation for the precautions that apply to every install, and licenses and compliance for regulatory details.

The firmware

The open-source firmware you can install on the controller is free and provided under its own licenses, which are listed with their upstream credits on the licenses & compliance page. Those licenses, not this page, govern your use of the firmware, and like essentially all open-source licenses they provide the software as-is, without warranty of any kind. Serin Labs does not charge for firmware, and no subscription is attached to it.

The Google Home and Alexa compatible firmware is free of charge as well. It is not open source and its source code is not published, so it carries no upstream license of its own, and these are its terms. Serin Labs grants you a license to download that build, keep copies of it, and install it on a Serin Controller or on another supported board you own. The third-party components it is built on are listed on the licenses & compliance page under their own licenses, which continue to govern those components. Like every other build, it is provided as-is, without warranty of any kind.

The Serin Link runs its own firmware, which is open source under the GNU General Public License, version 3, with its source published at Serin-Labs/serin-link on GitHub. Assembled Links ship with that firmware installed and update over a signed over-the-air channel, and reflashing a Link over USB stays available to you. Installing other firmware on a Link you own is permitted; see the limited warranty for what that does to coverage.

The browser flash tool

The browser flash tool installs firmware on a controller through a USB cable, locally in your browser. It is provided as-is. Selecting the wrong firmware, disconnecting the cable, or encountering a software error may require the board to be flashed again. The troubleshooting guide covers recovery. A controller purchased from Serin Labs that cannot be recovered is handled under the store policies. You assume the risk when installing firmware on hardware obtained elsewhere.

Purchases

Sales are governed by the store policies and the limited warranty, both of which are part of these terms. Direct orders are processed by Shopify under its own terms; Etsy orders are processed by Etsy under its own terms and Purchase Protection.

Joining the waitlist for a product we have announced but not yet released, through the contact form, creates no order, takes no payment, and binds neither you nor Serin Labs. It records your interest so that we can tell you when the product is available to order.

Third-party services and links

This site links to and relies on services that Serin Labs does not control, including GitHub, Discord, Shopify, Etsy, and Resend, which delivers contact form messages to our mailbox. Each service is governed by its own terms and privacy policy. Serin Labs is not responsible for their content or availability.

Community spaces

Our Discord server and GitHub repositories are open to the public. Treat other participants respectfully, do not post spam or malicious code, and follow each platform's rules. We may remove content or restrict access when necessary to maintain safe and useful community spaces.

Intellectual property

The text, images, and design of this site belong to Serin Labs unless credited otherwise. The open-source firmware belongs to its respective authors under the licenses listed on the licenses and compliance page. You may link to any page on this site.

Disclaimer of warranties

The site, documentation, browser flash tool, and free firmware are provided “as is” and “as available,” without warranties of any kind, express or implied, including implied warranties of merchantability, fitness for a particular purpose, and non-infringement. This disclaimer does not alter the return, replacement, and refund commitments for hardware stated in the store policies, or the coverage stated in the limited warranty.

Limitation of liability

To the fullest extent permitted by law, Serin Labs is not liable for indirect, incidental, special, or consequential damages arising from your use of the site, tools, or firmware, including damage to HVAC equipment, other hardware, or property, or loss of use or data. Our total liability for any claim is limited to the amount paid to Serin Labs for the product involved, or $50 if no purchase was made. Some jurisdictions do not permit certain limitations, so parts of this section may not apply to you.

Governing law

These terms are governed by the laws of the State of New Jersey, United States, without regard to conflict-of-law rules. If a court finds part of these terms unenforceable, the rest still applies.

Changes

If these terms change, this page and its revision date will be updated. Continued use of the site after a change constitutes acceptance of the updated terms.

Contact

Use the contact form for questions about these terms. We reply within 2 business days. To report a security problem in our firmware, this site, or our stores, follow the steps on the security page.