ROAMiQ Duoetto Control Module: Duoetto Gen 3 wiring and setup
Connect your Duoetto Gen 3 to ROAMiQ, wire the four controller circuits, pair during Guardian setup, and test temperature and power control.
Before you start
- Duoetto Gen 3 water heater and ROAMiQ Duoetto Control Module
- ROAMiQ 4-pin harness and matching Duoetto controller plug
- Two 3-way and two inline connectors if retaining the original controller, or two inline connectors without it
- A 12V supply for the chip, such as the house battery or a 12V circuit
- Wire cutters, wire strippers, and suitable insulated wiring materials
- ROAMiQ system ready for Guardian setup
Find the controller connection
The controller connection is exposed at the rear of the Duoetto. The matching controller plug connects here, whether you use the original controller, the ROAMiQ chip, or both.
The heater also has positive and negative DC power leads for a distribution-panel connection and a three-prong AC power connection. These are separate from the four-wire controller harness. Follow the Duoetto installation manual for heater power wiring.
Match the circuits
The Duoetto controller harness only carries the data pair, red and blue, to the chip. It doesn't power the chip: the chip's 12V and ground come from its own 12V supply. Keep every circuit separate.
| ROAMiQ pin | Function | Connects to |
|---|---|---|
| 1 | RS485A | Duoetto red |
| 2 | RS485B | Duoetto blue |
| 3 | GND | 12V supply negative |
| 4 | 12V positive | 12V supply positive |
The Duoetto white and black wires don't connect to the chip.
Choose your wiring arrangement
Keep the original controller
Use a 3-way connector on red and another on blue. Each joins the Duoetto plug harness, the original controller and the ROAMiQ harness. Rejoin white and black between the plug harness and the controller with inline connectors, as they were before. Power the chip from its own 12V supply. This keeps a physical controller alongside ROAMiQ.
Connect without the original controller
Use an inline connector on red and another on blue to join the Duoetto plug harness to ROAMiQ pins 1 and 2. Insulate the Duoetto white and black wires separately; they aren't used. Power the chip from its own 12V supply. You still need the matching plug that fits the Duoetto controller connection.
Wire and pair the chip
Prepare the controller cable
With both power sources disconnected, unplug the controller harness and cut its cable at an accessible point. Leave enough wire on both sides for secure connections. Identify all four conductors before stripping them.
Connect the data wires
For the controller-retained arrangement, join red in one 3-way connector and blue in another, each with the Duoetto plug harness, the original controller and the ROAMiQ harness. Rejoin white and black between the plug harness and the controller. Without the controller, join red and blue to the ROAMiQ harness with one inline connector each, and insulate white and black separately.
Match red to RS485A (pin 1) and blue to RS485B (pin 2). Identify the ROAMiQ connections by pin; do not rely on color alone if your supplied harness differs.
Wire the chip's power
Run the chip's 12V (pin 4) to a 12V source, such as the house battery or a 12V circuit. Run GND (pin 3) to the negative of the same supply. Don't power the chip from the Duoetto harness.
Inspect and secure the harness
Check that each wire is fully inserted and firmly held. Confirm no copper is exposed and no connector joins different circuits. Plug the matching harness into the Duoetto controller connection and seat the ROAMiQ harness in the chip. Secure the chip and wiring against vibration, heat, sharp edges, and strain.
Restore power and run Guardian setup
Restore heater power after the wiring checks and the heater's required preparation, and switch on the chip's 12V supply. The ROAMiQ chip should power on and become available to pair during Guardian setup. Complete pairing and select Duoetto in the Water Heater setup section.
Test temperature and power control
Confirm the Duoetto's reported temperature and heater-on status are available in ROAMiQ. Toggle heater power once and check that the reported state changes. Select a nearby target temperature and confirm that the reported set temperature reaches it. Allow each command to finish before sending another.
If retaining the original controller, test its buttons as well as ROAMiQ and confirm both operate reliably.
What you can control
| Control or reading | Available function |
|---|---|
| Heater power | Toggle on/off |
| Target temperature | Set 86–140°F in 1°F increments |
| Temperature adjustment | Increase or decrease the target |
| Temperature readings | Reported actual and set temperature |
| Status | Heater on/off and controller display mode |
Troubleshooting
The chip does not power on
Disconnect power before inspecting the wiring. Check that the chip's 12V supply is on, that pin 4 goes to its 12V positive and pin 3 to the same supply's negative, and that the ROAMiQ harness is seated in the chip. The Duoetto harness doesn't power the chip.
The chip pairs, but the heater does not respond
Check red RS485A and blue RS485B against the pin table. Inspect the splices and the matching Duoetto plug. If the original controller is connected, disconnect it and test again with the arrangement without the original controller.
The target temperature does not change immediately
ROAMiQ adjusts the target through controller-style commands. Allow the adjustment to finish and check the reported set temperature before issuing another command.