The IntesisBox Tank template controls the hot water tank (DHW) functions of Panasonic Aquarea H/J heat pump systems through the IntesisBox PA-AW2-MBS-1 gateway (order code INMBSPAN001A000). TapHome communicates with the gateway via Modbus RTU over RS-485, and the gateway translates commands to the Panasonic proprietary protocol on the Aquarea hydro unit.
The template covers tank-specific registers H:30–H:39, providing system ON/OFF control, working mode selection, water temperature monitoring and setpoint, heating timing configuration, and Legionella sterilization settings.
Hardware connection
System overview
The INMBSPAN001A000 gateway connects to the Panasonic Aquarea hydro unit via a dedicated cable (supplied with the gateway) to the CN-CNT socket on the hydro unit’s electronic circuit board. External power is not required — the gateway is powered from the hydro unit connection.
Up to 63 INMBSPAN001A000 gateways can be connected on a single Modbus RTU bus, each with a unique slave address.
Wiring diagram
Connection to the hydro unit:
- Disconnect mains power from the Aquarea hydro unit
- Open the front cover to access the electronic circuit
- Locate the socket connector marked CN-CNT
- Connect the supplied cable — short uncovered end to the INMBSPAN001A000, long uncovered end to CN-CNT
- The gateway can be placed inside or outside the hydro unit
RS-485 wiring (EIA-485):
Connect the EIA-485 bus wires to the 2-pole plug-in terminal block on the gateway:
- A+ → A+/D+ on TapHome RS-485
- B- → B-/D- on TapHome RS-485
Important — Cable and topology
Maximum bus distance is 1,200 m. Loop or star topologies are not allowed — use daisy-chain only. Do not modify the length of the cable supplied for the hydro unit connection. A 120 Ω termination resistor is required at each end of the bus.
Technical specifications
- Dimensions: 93 x 53 x 58 mm
- Operating temperature: 0°C to +60°C
- Protocol: Modbus RTU Slave, EIA-485
- Baud rate: 9600 (default), configurable 2400–115200
- Communication: 8N2 (default), auto-detects 8N1
- Max devices: 63 on a single bus
- External power: Not required (powered from hydro unit)
- Mounting: DIN rail or wall
Configuration
DIP switch layout
The gateway has three DIP switches: SW1, SW3 and SW4. All configuration changes require a system power cycle to take effect.
Modbus slave address (SW3)
SW3 positions P1–P6 set the Modbus slave address using binary encoding (range 0–63). Default address is 1 (only P1 ON, all others OFF).
The slave address configured on the gateway must match the Slave ID in the TapHome template import parameters.
Baud rate (SW3 + SW4)
| SW3-P7 | SW3-P8 | SW4-P3 | Baud Rate |
|---|---|---|---|
| OFF | OFF | OFF | 2400 bps |
| ON | OFF | OFF | 4800 bps |
| OFF | ON | OFF | 9600 bps (default) |
| ON | ON | OFF | 19200 bps |
| OFF | OFF | ON | 38400 bps |
| ON | OFF | ON | 57600 bps |
| OFF | ON | ON | 76800 bps |
| ON | ON | ON | 115200 bps |
For TapHome: Use the default 9600 bps (SW3-P7=OFF, SW3-P8=ON, SW4-P3=OFF).
Termination resistor (SW4-P4)
The gateway has an on-board 120 Ω termination resistor activated via SW4-P4:
- SW4-P4 OFF (default) — no termination
- SW4-P4 ON — 120 Ω termination resistor connected
For TapHome: TapHome Core has a built-in 120 Ω resistor on its BUS terminals. Set SW4-P4 to ON only on the last gateway on the bus. All other gateways should have SW4-P4 OFF.
Temperature format (SW4)
| Switch | Description |
|---|---|
| SW4-P1 OFF (default) | Temperature in degrees (x1) |
| SW4-P1 ON | Temperature in decidegrees (x10) |
| SW4-P2 OFF (default) | Temperature in Celsius |
| SW4-P2 ON | Temperature in Fahrenheit |
The template expects Celsius format. The desired temperature register uses /10 scaling, which works with either x1 or x10 temperature format depending on the firmware behavior.
Device capabilities
Tank system control
- System ON/OFF (H:30) — turns the hot water tank system on or off
- Tank Working Mode (H:31) — selects between Normal, Eco, and Powerful heating modes
Water temperature
- Water Temperature (H:32 / H:33) — reads the current water temperature and allows setting the desired temperature. The setpoint uses /10 scaling (e.g., register value 500 = 50.0°C). Typical setpoint range is 40–75°C. This device polls at 1-second intervals for responsive temperature monitoring.
Heating timing
- Heat-up Interval (H:34) — configures the duration of the heating cycle in seconds
- Operation Interval (H:35) — configures the operating time window in hours, with 0.5-hour resolution (register value is 2× the actual hours)
- Booster Delay Time (H:36) — configures how long to wait (in minutes) before activating the booster heater when the heat pump alone cannot reach the target temperature
Sterilization (anti-Legionella)
The template provides full control over the Legionella prevention sterilization cycle:
- Sterilization ON/OFF (H:37) — enables or disables the sterilization function. Uses a non-standard write encoding (value × 0xAA) specific to the Panasonic Aquarea protocol
- Sterilization Boiling Temperature (H:38) — target temperature for the sterilization cycle, typically 60–75°C
- Sterilization Continuing Time (H:39) — duration in seconds for maintaining the sterilization temperature
Legionella bacteria are killed at temperatures above 60°C. A common configuration is 65°C for 600 seconds (10 minutes), run weekly. Consult local regulations for specific requirements.
Additional capabilities
The INMBSPAN001A000 gateway exposes a comprehensive register map covering the entire Aquarea system — including main heating/cooling system ON/OFF, operation mode selection, zone control (up to 2 zones with independent setpoints), outdoor/inlet/outlet water temperatures, energy consumption and generation monitoring, quiet mode, holiday mode, powerful mode, error codes, and unit configuration readback. The IntesisBox Tank template focuses specifically on the hot water tank (DHW) registers H:30–H:39. The remaining registers can be added in a future template update or configured as custom Modbus devices in TapHome.
LED status indicator
The gateway has LED indicators for operational status:
| LED State | Description |
|---|---|
| Steady green | Communication with hydro unit OK |
| Fast blink green | No communication with hydro unit (searching) |
| Slow blink green | Communication with hydro unit lost (retrying) |
Yellow LED (L1):
| State | Description |
|---|---|
| LED blinking (500ms ON / 500ms OFF) | Communication error |
| LED flashing (100ms ON / 1900ms OFF) | Normal operation |
Troubleshooting
No Modbus communication (gateway not responding)
- Check RS-485 wiring:
- A+ correctly connected to A+/D+ on TapHome
- B- correctly connected to B-/D- on TapHome
- Verify the Modbus slave address on DIP switch SW3 (P1–P6) matches the TapHome template Slave ID
- Check the baud rate configuration — TapHome and the gateway must use the same baud rate (default 9600)
- Check the termination resistor — the last device on the bus should have 120 Ω enabled (SW4-P4 ON)
- Confirm TapHome is set to: 9600 baud, no parity, 1 stop bit
Gateway LED not lit
- Verify the hydro unit is powered on
- Check the CN-CNT cable connection between the gateway and the hydro unit
- The gateway requires the hydro unit to be powered — there is no external power option
Gateway LED blinking fast (searching for hydro unit)
- Check the CN-CNT cable — ensure both ends are properly seated
- Verify the hydro unit model is compatible (Aquarea H or J generation)
- Power cycle the system — disconnect and reconnect mains power to the hydro unit
Temperature readings incorrect
- Check the temperature format DIP switch (SW4-P1 and SW4-P2) — the template expects Celsius
- Verify the setpoint is within the valid range (typically 40–75°C for tank water)
The INMBSPAN001A000 is a legacy product. The replacement model INMBSPAN001A100 is functionally identical for Modbus register purposes and works with the same TapHome template.
