4-Zone Wall Controller Firmware Update: Latest Features for Existing Customers

If you have already purchased a TekOnline 4-Zone Wall Controller, the latest firmware adds a few useful features without changing the core wall-control experience.

The front buttons still work locally at the wall, but the controller now gives you better behavior for pressure-relief style spill setups, better visibility in Home Assistant, and safer network behavior when you have more than one controller on site.

Current public firmware version:

2026.05.17-v2-hold-dimmer-unique-spill-invert

What Stays the Same

The basics are unchanged:

each front button still controls its matching zone
a short press still toggles that zone
hold-to-dim still adjusts the zone level
the controller still works locally even if Home Assistant is offline

That part was kept stable on purpose.

New Feature: Spill Zone Support

The biggest firmware addition is Spill Zone support.

In Home Assistant, you can now choose:

Off
Zone 1
Zone 2
Zone 3
Zone 4

If a spill zone is selected and every other zone is off, the controller can automatically open that nominated spill zone.

This is useful on systems where you want one zone available for pressure relief when the rest of the zones are closed.

New Feature: Spill Now Shows on the Wall Buttons

The spill behavior is now reflected on the wall itself.

For example:

A user turns all zones off.
The controller detects that the configured spill zone should open.
That spill zone relay turns on.
The matching wall-button illumination also turns on.

That means the wall controller gives a more honest picture of what the system is actually doing, instead of only showing what was pressed manually.

New Feature: Better Visibility in Home Assistant

The latest firmware also exposes more useful diagnostic entities in Home Assistant.

These include:

Firmware Version
ESPHome Version
Spill Zone select
Spill Active
Zone 1 Relay Active through Zone 4 Relay Active
Zone 1 Button Illumination through Zone 4 Button Illumination
Zone 1 Relay Effective Level through Zone 4 Relay Effective Level

This is especially useful if you are away from the hardware and want to confirm:

whether spill is active
which relay is actually being driven
which front-button illumination level the controller is currently showing
which TekOnline firmware build is installed

New Feature: Per-Zone Relay Inversion

Some HVAC interfaces expect active-high outputs and some expect active-low outputs.

If a customer's system appears backwards, for example off in Home Assistant turns a zone on, the latest firmware provides per-zone inversion switches.

In Home Assistant, look for:

Zone 1 Relay Inverted
Zone 2 Relay Inverted
Zone 3 Relay Inverted
Zone 4 Relay Inverted

Turn on the inversion switch for any zone that behaves backwards.

If all zones behave backwards, turn on all four inversion switches.

New Feature: Multiple Controllers on One Network

The latest firmware also improves multi-controller installs.

Each controller now adds a unique suffix to its network name, which helps avoid hostname clashes when you have more than one 4-Zone Wall Controller on the same network.

Instead of two devices both trying to appear as the same name, each one will present with its own unique hostname.

That makes discovery and management in ESPHome and Home Assistant much cleaner.

Why This Update Matters

This update is mainly about making the controller easier to trust in real systems:

the wall still feels simple to use
spill logic is configurable from Home Assistant
button illumination reflects effective output, not just manual presses
relay behavior is easier to inspect remotely
relay polarity can be corrected without editing GPIO code
the installed TekOnline firmware version is visible in Home Assistant
multi-device installs are cleaner

In short, the controller is still simple for day-to-day use, but more transparent and more robust for advanced installs.

Should Existing Customers Update?

You should consider the latest firmware if:

you want a nominated spill zone
you want to inspect button illumination or relay behavior in Home Assistant
your zones behave backwards and need relay inversion
you want the installed firmware version visible in Home Assistant
you are installing more than one wall controller on the same network
you want the latest dimming and spill behavior improvements

If your current controller is already doing exactly what you need and you do not need spill or extra visibility, you may prefer to leave it as-is.

Need Help Updating?

If you want the latest firmware on your existing 4-Zone Wall Controller, use the current public YAML:

tekonline-4zone-wall-controller-v2026-05-17.yml

If WordPress supplies the file as .txt, rename it to .yml before adding it to ESPHome:

tekonline-4zone-wall-controller-v2026-05-17.txt

to:

tekonline-4zone-wall-controller-v2026-05-17.yml

If the controller is already online and running ESPHome, it can usually be updated with Install > Wirelessly in the ESPHome Dashboard.

If ESPHome cannot find the device by hostname, temporarily add the controller's local IP address to your own copy of the YAML:

wifi:
  use_address: 192.168.1.123

Replace 192.168.1.123 with the controller's actual IP address. Do not add a private IP address to the public download file.

If the ESP32 flash has been wiped, use USB flashing first. OTA only works once ESPHome firmware is already running and reachable on the network.

If you want help, contact TekOnline.

Include:

your current Home Assistant setup
whether the controller is already connected to ESPHome
whether you want spill enabled
whether any zones are inverted
the firmware version currently shown in Home Assistant, if available
how many controllers you have on the network

That makes it much easier to recommend the right firmware variant for your install.