Vaillant aroTHERM plus VWL 75/8.1 A

Compatibility

Compatible with EpiSensor Edge through an EpiSensor ZEM on its supply

Vaillant documents local EEBUS pairing and a partner Cloud API through compatible VRC 700(f)/720(f) regulators and VR 920/921/940(f) internet modules, and its outdoor A/B link belongs to the indoor unit. Edge measures the heat pump through an EpiSensor ZEM with a CT on its 230 V supply; a heat meter on the delivered-heat boundary completes the COP.

Identify the installed indoor unit, regulator and internet module. Site check: put the ZEM CT on the circuit that feeds only the heat pump, and add the auxiliary-heater and circulation-pump feeds inside the COP boundary. Preserve the internal outdoor/indoor A/B link. Use the OEM app procedure below for EEBUS or Cloud API partners, and keep control changes within the commissioned heating design.

Connect it with

• Wireless 3-Phase Electricity Monitor ZEM-65 From €625 ex VAT Configure
• Gateway ZGW-20 From €899 ex VAT Configure

Models

Specifications

The exact outdoor unit is a 230 V R290 monobloc in Vaillant's 35/55/75/8.1 manual, article 8000033711 for AT, CH and DE. The manual calls it a domestic outdoor heat-pump unit and requires a permitted indoor partner. It is not a stand-alone commercial BMS controller.²

Exact article and markets

VWL 75/8.1 A 230V, 8000033711; Austria, Switzerland, Germany²

A−7/W35 performance

6.94 kW heating output / 2.36 kW electrical input; COP 2.94 at the stated test point³

Compressor supply

230 V, 50 Hz; installed circuit and EVU arrangement require qualified design^2, 3

Refrigerant

R290, 0.9 kg in the VWL 75/8.1 product table³

Outdoor to indoor communication

Two-wire A/B link marked Modbus in the appliance diagram, 50 m maximum; internal Vaillant system connection²

System regulator link

eBUS from the indoor unit to a Vaillant system regulator in the manual's typical arrangement²

Dimensions and mass

965 × 1100 × 450 mm (H × W × D), 130 kg³

Sound power

57.4 dB(A) day / 46.2 dB(A) night in the July product table; siting rules still apply³

Interface

Documented measurements and integration boundaries for aroTHERM plus VWL 75/8.1 A.

• The current installation manual's validity table binds VWL 75/8.1 A 230V to article 8000033711 in Austria, Switzerland and Germany. Check that article number rather than the broad aroTHERM plus name, which also covers 400 V and S3 variants.
• The outdoor A/B link connects directly to the Vaillant indoor unit with A-to-A/B-to-B polarity and a 50 m limit. Use the regulator and internet module for system-level integration; preserve this internal appliance cable.
• The March manual permits the outdoor unit with specified VIH QW 190/7, VWZ MEH 97/7 or VWZ AI /7 230V indoor arrangements. It names the indoor regulator and system regulator separately. Confirm the actual hydraulic and controller topology before selecting any external interface.
• Vaillant's July product sheet states 6.94 kW heat output and 2.36 kW electrical input at A−7/W35 for this model (COP 2.94). These are test-point values, not a guaranteed whole-building load or measured seasonal performance. Meter electrical input and delivered heat separately if a site performance claim matters.
• Vaillant documents two system-level integration routes: local EEBUS and its partner Cloud API. Its prerequisites name VRC 700(f)/720(f) and VR 920/921/940(f), commissioned through myVAILLANT. The exact-model case study uses sensoCOMFORT 720 with VR 940f. Pairing and available functions are set by the selected energy-management partner.
• For EEBUS, enable the app’s Network settings > EEBUS, start pairing in the partner system, select that partner and establish trust. Then enable Energy management in the app if the chosen partner requires it. Vaillant currently excludes heat-pump cascades from the energy-management function.
• The partner Cloud API process starts in the partner app with the internet-module serial number. The myVAILLANT account holder receives an email link and approves the connection in the web portal. Use a supported partner rather than assuming the consumer account provides a public API token.
• Vaillant’s EnergiePLUS FAQ allows one energy-management system at a time and excludes a simultaneous connection to another system such as EEBUS. Record the current optimisation owner before pairing a new partner.

Setup

1. Identify the installed system

   Record outdoor article 8000033711 and the indoor unit. Identify the regulator and internet module; Vaillant’s interface guide names VRC 700(f)/720(f) with VR 920/921/940(f). Check that myVAILLANT has been commissioned and the system is online.

2. Define what to measure

   Choose heat output, electricity, flow/return temperatures and operating-state observations. Meter all included compressor, auxiliary-heater and circulation-pump inputs, and use a heat meter across the declared delivered-heat boundary. Record interval and units with each source.

3. Pair a local EEBUS partner

   Open Network settings > EEBUS in myVAILLANT and enable it. Start the connection in the supported partner’s solution, select that partner in myVAILLANT and establish trust. Open Energy management in the app and enable it where required. Record the data and functions that become available.

4. Or connect an approved cloud partner

   Start in the energy-management partner’s app and enter the internet-module serial number. Use the same account email as myVAILLANT, open the emailed web-portal link and approve the connection. Check spam and the serial number if the email does not arrive.

5. Check optimisation ownership

   Check whether EnergiePLUS or another energy manager is active. Vaillant allows only one energy-management system at a time. Its current interface guidance also excludes cascade energy management and requires a suitable hot-water or heating buffer for thermal-storage functions.

6. Compare readings and preserve controls

   Compare partner values with the local controller and meter displays over matching intervals. Save timestamps and distinguish measured meter totals from controller estimates. Preserve the internal A/B connection and commissioned frost, DHW and comfort settings while establishing monitoring.

Common questions

Does the outdoor unit have a Modbus port for a BMS?

The installation drawing labels the outdoor A/B link Modbus, but section 7.8 connects it directly to the Vaillant indoor unit and limits the cable to 50 m. The retained manual provides no third-party register list or permission to share that appliance link.²

Is VWZ AI /7 a Modbus gateway?

The manual lists VWZ AI /7 230V as a permitted indoor control arrangement and shows eBUS between the indoor unit and system regulator. It describes no generic BMS Modbus service on VWZ AI.²

Can a utility signal safely turn off the heat pump for flexibility?

The manual discusses EVU blocking and indoor-unit S21 as installation choices, but does not grant third-party control authority. The heating-system owner must approve frost, hot-water, comfort and restart behaviour before any site-specific response design.²

Can EnergiePLUS and another energy manager operate together?

Vaillant’s current FAQ permits one energy-management system at a time and excludes a simultaneous connection to another manager, including EEBUS. Check the existing optimisation owner before changing the partner connection.⁶