Using Nest or ecobee with Mitsubishi Electric AC: CN105 and M-NET explained
Mitsubishi Electric equipment covers two very different worlds. In homes, there are wall splits, ducted units and ceiling cassettes, usually run by a handheld or simple wired remote. In larger buildings, there's City Multi, Mitsubishi Electric's VRF range, tied together by its own control network. Both can work with a smart thermostat, but they connect in different places.
CN105: the port on Mitsubishi Electric indoor units
Most Mitsubishi Electric residential indoor units have a connector on the main control board called CN105. It's the port Mitsubishi Electric's own Wi-Fi interfaces use. The installation manual for the MAC-588IF-E interface puts it plainly: locate the CN105 port on the main control PCB and connect the Wi-Fi interface.
Because CN105 is a proper digital connection to the indoor unit, it's also a good place for a thermostat adapter. CN105 is on the list of connectors supported by DropAir's Mini and Pro adapters.
If a Wi-Fi interface is already fitted
If you already have MELCloud or kumo cloud Wi-Fi on the unit, it's probably plugged into CN105. Tell us before ordering. The adapter and the Wi-Fi interface may need the same port, and we'll advise on which control route makes sense for you.
M-NET: the City Multi network
City Multi VRF systems use M-NET, a communication bus made of two non-polar wires daisy-chained between components. It links indoor units, outdoor units and central controllers across a building.
M-NET is on DropAir's supported connection list. City Multi installations are almost always projects, with many indoor units and often a central controller or building management system already in place, so the Pro 6X is usually the right fit. It's configured per site and can bring the AC into platforms like Lutron, Control4 or Crestron as well as Nest and ecobee.
Which model for which Mitsubishi Electric system
| Equipment | Connection | Typical model |
|---|---|---|
| Wall split (MSZ and similar) | CN105 | Mini 6 or Mini 6S |
| Ducted or ceiling unit (SEZ, PEAD and similar) | CN105 or wired controller connection | Mini 6 or Mini 6S |
| City Multi VRF indoor units | M-NET | Pro 6X, or Mini 6S per unit |
The model families in that table are examples. The rating label on your indoor unit gives the exact code, and that's what we check.
What changes when you add a smart thermostat
The thermostat becomes the controller for that room. You set temperatures and schedules in the Nest or ecobee app, and the adapter turns those into commands the Mitsubishi Electric unit understands. The adapter powers the thermostat with 24V, so no extra transformer is needed.
If you choose the Mini 6S, the original controller can stay in the system, keep showing status and fault codes, and mirror the thermostat's settings.
Before you order
- The full indoor unit model from the rating label.
- Whether a Wi-Fi interface is already fitted, and its model.
- The model of the current controller, and a photo of its wiring.
- For City Multi: a list of indoor units and any central controller model.
Summary
On Mitsubishi Electric home units, the connection point is usually CN105, the same port the brand's Wi-Fi interfaces use. On City Multi VRF, it's the M-NET bus. DropAir adapters support both. Send us the rating label and a photo of the controller and we'll confirm the right model.