The short answers, with links to the full pages. If your question is not covered, ask us directly or ask in Discord.

Before you buy

Will it work with my Mitsubishi unit?

It works with most Mitsubishi units that have an internal CN105 connector: wall-mount, floor, cassette, ducted, and P-series, plus rebranded Trane and American Standard units. Type your model number into the compatibility checker for an instant answer. Mitsubishi Heavy Industries (SRK/SRC/SRF) and Ecodan air-to-water units are not compatible.

I already have a wall controller. Can I run both?

No. Wired wall controllers such as the MHK2, MHK1, PAC-SDW01RC-1, and PAR-series panels use the same CN105 port, and most indoor units have only one. CN105 splitters are not supported, so you must choose one wired interface. The handheld infrared remote does not use CN105 and continues to work. Full comparison: a less expensive alternative to the MHK2 wall controller.

HomeKit or ESPHome: which should I choose?

Use the HomeKit-compatible firmware if your home runs on Apple Home and Siri; use ESPHome if you run Home Assistant. For Google Home, Amazon Alexa, or SmartThings, use the Matter-compatible build in beta. All builds are free and local, and you can reflash to switch anytime. See choose your firmware for all three routes, then follow the Apple Home setup guide, Home Assistant setup guide, or Matter setup guide.

How does it compare to the MHK2 or Kumo Cloud?

The controller, from $35, gives you full mode, temperature, fan, and vane control, the same as Mitsubishi's $179 to $475 wall controllers or the $227 Kumo Cloud adapter, but locally, with no cloud account and no subscription. See every option compared.

Setup and firmware

What do I need to flash the firmware?

You need a USB-C data cable and Chrome, Edge, or Brave on a computer. Safari and Firefox do not support the required Web Serial connection. The browser flash tool runs locally and does not require a software installation. Choose your platform and install its firmware before setup.

How do firmware updates work? Is there a subscription?

Firmware updates are free and do not require a subscription. ESPHome and the HomeKit-compatible firmware are open source; the Matter-compatible build is free to install, but its source is not published. After the initial USB installation, ESPHome installs updates from its dashboard; HomeKit-compatible and Matter-compatible firmware update through their built-in web interface. You can also reflash over USB at any time, including when switching platforms. Follow the updates and reset guide; the licenses page explains each build.

Does it need the internet to work?

No. Control is local on your network. For control away from home you use your platform's own remote access: an Apple Home hub (Apple TV or HomePod) for HomeKit, or Home Assistant remote access for ESPHome.

Orders and shipping

Where do I buy, and how fast does it ship?

Directly on this site, with checkout handled by Shopify, or through our Etsy shop. Orders ship from NJ within 1–2 business days, with free US shipping on direct orders of $35 and up.

What is the return policy?

Returns and exchanges are accepted within 30 days of delivery, and orders can be cancelled within 12 hours of purchase. Defective units are replaced or refunded in full, and so is a controller that turns out not to fit your unit, flashed or not. The details live on the store policies page.

Is there a warranty?

Yes. Every product carries a one-year limited warranty against manufacturing defects, with replacement or a refund and shipping covered in both directions. That is on top of the 30-day return window and the replacement or refund commitment for an item that arrives damaged, defective, or incorrect. Full terms are on the limited warranty page.

What should I do if my controller arrives damaged or does not power on?

First review the troubleshooting guide, because a charge-only USB cable is the most common cause of this problem. If the controller is defective, use the contact form, or message the shop on Etsy for an Etsy order. We will replace it or provide a full refund, including shipping.