The Intesis PA-AW-MBS-1 (TapHome template name IntesisBox Climate) is a Modbus RTU gateway that connects pre-H generation Panasonic Aquarea air-to-water heat pumps to a Modbus RTU (EIA-485) network. The gateway is powered directly from the Aquarea system — no external supply is required — and TapHome communicates with it as a Modbus RTU master over an RS-485 bus.

This template exposes only the Climate Configuration section of the gateway (holding registers H:10–H:27): operating mode, Normal/Eco/Powerful working mode, weather-compensation heating curve anchors, heating cut-off limits, backup heater threshold, and the cooling and heating setpoints. The General System Control, Tank/DHW, Maintenance, Unit Configuration and System Configuration sections of the gateway are not covered by this template.

Legacy product. The PA-AW-MBS-1 is discontinued and was designed for the pre-H generation of Panasonic Aquarea units. For Panasonic Aquarea H or J generation heat pumps use the successor PA-AW2-MBS-1 / INMBSPAN001A000, which has its own TapHome compatibility template with a different register map (H:0–H:86). Current HMS active replacement is INMBSPAN001A100.

Hardware connection#

System overview

Up to 63 PA-AW-MBS-1 devices can share a single Modbus RTU EIA-485 network. Each gateway acts as a Modbus slave linked to one Panasonic Aquarea unit. The bus connects to a Modbus RTU master (TapHome Core, SCADA, PLC or BMS).

Connection to the Aquarea unit

The gateway connects directly to the Aquarea system using the cables supplied by Intesis. The wiring topology depends on the Aquarea variant:

• Monobloc — connect the PA-AW-MBS-1 between the Aquarea Control Panel and the Panasonic cable coming from the outdoor unit.
• Bibloc — connect the PA-AW-MBS-1 directly to the Aquarea indoor unit using the supplied cable plus the Panasonic cable.

The PA-AW-MBS-1 is powered through the Aquarea connection (K1 / K2 cables). No external 12/24 V supply is needed. The Aquarea IR remote, wired Control Panel and Modbus RTU can be used simultaneously — values shown on the remote and via Modbus can momentarily differ because the Aquarea system is not strictly synchronous.

Connection to the EIA-485 bus

Wire the TapHome RS-485 bus to the plug-in screw terminal block on the PA-AW-MBS-1:

• Topology: bus only — loop and star topologies are not allowed
• Maximum length: 1,200 m
• Polarity: observe A+/B- polarity strictly
• Termination: 120 Ω resistor required at each end of the bus
• Fail-safe biasing: must be provided by exactly one device on the bus (the Modbus master)

The PA-AW-MBS-1 provides the on-board 120 Ω terminator via DIP switch S4.4 and the fail-safe biasing via internal jumper JP1 (under the top cover). Because the biasing circuit also acts as a terminator, activate only one of the two at the PA-AW-MBS-1 end (S4.4 = ON or JP1 placed) — not both. Place the biasing/terminating device at one end of the bus.

Configuration#

DIP-switch layout

The PA-AW-MBS-1 has three DIP-switch banks:

• S1 — not used on v1.4 hardware
• S3 — 8 positions: Modbus slave address (positions 1–6) + baud rate (positions 7–8)
• S4 — 4 positions: temperature scaling (position 1) + EIA-485 termination (position 4); positions 2–3 reserved

All DIP-switch changes require a power cycle to take effect (the gateway is re-powered by the Aquarea system — cycle the Aquarea unit or disconnect the K1 cable).

Enabling Modbus communication

The factory defaults are slave ID 1, 9600 bps, 8N1 — which matches the TapHome default and is sufficient for most installations. Follow this procedure to commission the gateway:

1. Mount the PA-AW-MBS-1 (DIN rail or wall) close to the Aquarea Control Panel (Monobloc) or indoor unit (Bibloc).
2. Connect the supplied K1 (Aquarea unit) and K2 (Remote controller) cables. The gateway powers up from the Aquarea system.
3. Set the Modbus slave address (0–63) on S3 positions 1–6 using 6-bit binary encoding. Leave the default (address 1) if only one gateway is on the bus.
4. Set the baud rate on S3 positions 7–8 — leave the default (9600 bps, position 7 = ON, position 8 = OFF).
5. Set temperature scaling on S4 position 1: OFF = degrees (×1, default), ON = decidegrees (×10). See the admonition below before changing this switch.
6. If the PA-AW-MBS-1 is at one end of the EIA-485 bus, enable the internal 120 Ω terminator by setting S4 position 4 = ON. Otherwise leave it OFF.
7. Wire A+/B- to the TapHome Core RS-485 bus.
8. Power-cycle the Aquarea unit so DIP-switch changes are applied.
9. In the TapHome Configurator, import this template, set the Modbus slave ID to match S3 and verify the gateway responds on the bus.

Modbus slave address (S3 positions 1–6)

Slave address 0–63 is encoded in binary on S3 positions 1–6 (LSB = position 1). Default: address 1 (S3.1 = ON, all other address bits OFF). All 63 gateways on a single bus must have a unique address.

Baud rate (S3 positions 7–8)

TapHome default is 9600 bps, 8N1 — leave the defaults unless the bus runs at a non-standard rate.

Temperature format (S4 position 1)

Scaling inconsistency. The cooling setpoint register H:23 is hard-coded with /10 scaling in this template (raw value divided by 10 on read, multiplied by 10 on write), while the heating curve anchors (H:12–H:20) and heating setpoint (H:24) use raw values. Per the PA-AW-MBS-1 manual §3.4, the S4.1 switch selects the scaling globally for all temperature registers — a single DIP setting cannot satisfy both behaviours. The template is internally consistent only if the real gateway behaves this way on the target firmware. Verify readings against the Aquarea remote controller before relying on setpoints in smart rules. See inconsistency INC-2 below.

EIA-485 termination (S4 position 4)

Enable S4.4 only on the PA-AW-MBS-1 if it is at one end of the bus and JP1 is not placed. Activating both the on-board terminator and the JP1 biasing jumper simultaneously will over-load the bus.

TapHome import parameters

When importing the template in TapHome Configurator, provide:

• Slave ID — the Modbus slave address configured on S3 positions 1–6 (default 1)
• IP Address — ignored on TapHome Core with a native RS-485 bus; used only if the RS-485 segment is routed through a Modbus TCP-to-RTU converter

TapHome line settings for Modbus RTU: 9600 bps, 8N1 or 8N2 (the PA-AW-MBS-1 accepts either). Function codes supported by the gateway: 3 Read Holding Registers, 4 Read Input Registers, 6 Write Single Register, 16 Write Multiple Registers (length must always be 1 per write request).

Device capabilities#

Operating mode and working mode

• Climate Operating Mode (H:10) — Off, Heat or Cool selector. In the PA-AW-MBS-1 v1.4 manual this register is documented as read-only, but the TapHome template exposes it as writable. See inconsistency INC-3 below.
• Climate Working Mode (H:11) — energy profile preset: Normal, Eco (Thermoshift decrease) or Powerful (Thermoshift increase). This register is only configurable via Modbus — the Aquarea IR remote and wired Control Panel do not expose the working mode.

Weather-compensation heating curve

The weather curve delivers a warmer water setpoint when it is cold outside and a cooler setpoint in mild weather. Configure it with four register pairs — two outdoor-temperature anchors and their matching water setpoints:

• Outdoor Temp for Heating at Low Water Temp (H:12) — upper outdoor anchor (range −15 to 15 °C)
• Outdoor Temp for Heating at High Water Temp (H:13) — lower outdoor anchor (range −15 to 15 °C)
• Water Setpoint for Heating at Low Outdoor Temp (H:14) — water setpoint at the cold end of the curve (range −25 to 15 °C offset)
• Water Setpoint for Heating at High Outdoor Temp (H:15) — water setpoint at the mild end of the curve (range −25 to 15 °C offset)

Thermoshift and heating limits

• Water Current Thermoshift (H:16) — active offset applied to the water setpoint; combines the Working Mode preset (Eco/Powerful) and any user offset (range −5 to 5 °C)
• Outdoor Temp for Heating Off (Max) (H:17) — outdoor temperature above which heating is automatically stopped (range 5 to 35 °C)
• Outdoor Temp for Heating Off (Min) Selection (H:18) — toggles the low-outdoor cut-off; requires Aquarea protocol ≥ 2.01, returns invalid 0x8000 on older firmware
• Outdoor Temp for Heating Off (Min) (H:19) — outdoor temperature below which heating is stopped; takes effect only when H:18 is enabled (range −20 to −5 °C)
• Outdoor Temp for Heater On (H:20) — outdoor temperature threshold below which the Aquarea backup electric heater is allowed to assist (range −15 to 20 °C)

Cooling and heating setpoints

• Cooling Setpoint Temperature (H:23) — cooling water setpoint (manual range 5 to 20 °C); the TapHome template applies /10 scaling on read and ×10 on write. Requires the indoor unit to support Cool mode.
• Heating Setpoint Temperature (H:24) — current heating water setpoint, raw value with no scaling (manual range 20 to 70 °C). Manual documents this register as read-only but the template exposes it as writable — see inconsistency INC-3 below.

Auto-mode transitions (firmware-dependent)

The template exposes three additional registers that are not documented in the PA-AW-MBS-1 v1.4 manual and likely correspond to a later firmware revision of the Aquarea system. Behaviour must be verified on the actual hardware before relying on them in smart rules:

• Auto Heat-to-Cool Transition Temperature (H:25) — outdoor temperature at which Auto mode switches from heating to cooling
• Auto Cool-to-Heat Transition Temperature (H:26) — outdoor temperature at which Auto mode switches from cooling to heating
• Auto Operation Mode (H:27) — Off/Heat/Cool selector for Auto mode

See inconsistency INC-1 below.

The Eco and Powerful presets selected via Climate Working Mode (H:11) apply a fixed thermoshift offset configured in the gateway’s System Configuration section (registers 1000–1003, not exposed by this template). If the Eco/Powerful presets do not match your expectations, the offsets may need to be adjusted via a separate Modbus tool or a custom TapHome device.

Troubleshooting#

No Modbus communication

1. Verify the K1 and K2 cables are connected between the PA-AW-MBS-1 and the Aquarea unit — the gateway is powered through these cables, no LED lights if the Aquarea is off.
2. Check the L1 (yellow) LED behaviour:
   • Flashing slowly (100 ms ON / 1900 ms OFF) — gateway is configured and running normally.
   • Blinking (500 ms ON / 500 ms OFF) — communication error on the EIA-485 bus.
   • L1 and L2 pulse together (5 s ON) — device start-up.
   • L1 and L2 alternate blinking (500 ms) — flash checksum error, contact support.
3. Confirm the EIA-485 wiring polarity (A+ to A, B- to B) and that both bus ends have a 120 Ω terminator (see S4.4 and JP1 notes above).
4. Verify that the slave address on S3 positions 1–6 matches the value imported into TapHome, and that the baud rate on S3 positions 7–8 matches the TapHome Modbus line (default 9600 bps).
5. After any DIP-switch change, power-cycle the Aquarea unit so the new configuration is loaded.

Setpoint readings are 10x off

This indicates a mismatch between the temperature scaling expected by the template and the S4.1 DIP-switch setting. The template applies /10 scaling on H:23 (Cooling Setpoint) but reads H:12–H:20 and H:24 as raw values. If cooling setpoints look 10x off — or heating-related registers look 10x off — try toggling S4.1 and power-cycling the gateway. See inconsistency INC-2 below for details.

Register returns 0x8000 (invalid)

Several registers in the Climate Configuration section require Aquarea protocol version ≥ 2.01:

• H:18 (Outdoor Temp for Heating Off Min Selection)
• H:19 (Outdoor Temp for Heating Off Min)

If TapHome reads 0x8000 (32768) on these devices, the underlying Aquarea firmware is older than 2.01 and the register is blocked on the gateway. This is expected behaviour on legacy pre-H units — use only the Max limit (H:17) or the Heater On threshold (H:20) instead.

Writes to H:10 or H:24 have no effect

The PA-AW-MBS-1 v1.4 manual documents H:10 (Operating Mode) and H:24 (Heating Setpoint) as read-only registers, even though the TapHome template issues Modbus write commands. On some firmware revisions writes may silently fail. If Climate Operating Mode or Heating Setpoint do not respond to TapHome writes, control those values from the Aquarea Control Panel instead and use the template only for read-back. See inconsistency INC-3.

Consider upgrading to PA-AW2-MBS-1

If you are installing on a Panasonic Aquarea H or J generation unit, use the successor IntesisBOX PA-AW2-MBS-1 instead of this legacy template. The newer gateway exposes a richer register map (H:0–H:86, including DHW tank, dual-zone thermostats, energy consumption and detailed error codes) and is still actively supported by HMS Networks as INMBSPAN001A000 / INMBSPAN001A100.

Documented template quirks

• The template’s XML label for the Powerful preset reads Powerfull (double “l”) — cosmetic only, control function is unaffected.
• The read scripts for H:10, H:11 and H:27 use the non-standard Unt16 keyword (missing the “i”) instead of Uint16. TapHome’s parser accepts both; no action is needed.