TSUN + Vaillant

What Zerofy can do with TSUN and Vaillant

In practice

• Hot water is the simplest heat store: Autopilot can use the hot-water boost of your Vaillant heat pump to heat water in hours with surplus.
• Zerofy can also change the room temperature and flow temperature of your Vaillant heat pump, so space heating can shift into sunny hours.
• A heat pump draws roughly 1–3 kW while running – more than many small TSUN systems (typically 0.8–3 kW) produce, so solar covers only part of its consumption.
• Zerofy gets new TSUN data every 5 minutes. Heat pumps shouldn’t switch often, so set a minimum runtime in Autopilot.
• The boost is a one-time cylinder charge up to the hot-water setpoint you set in the myVAILLANT app (Zerofy can’t change that setpoint for Vaillant), so set it a few degrees higher than you strictly need if you want the tank to soak up more midday solar.
• The Zerofy integration for Vaillant is in beta.

What TSUN and Vaillant offer on their own

TSUN: TSUN has no heat pump or heating-rod control in its product range.

Vaillant: Vaillant has no PV energy manager of its own; instead the heat pump talks EEBUS over the VR 920/921/940f internet module to external energy managers, and Vaillant’s cloud API is opened to partner services. Both need a VRC 700(f) or VRC 720(f) controller and a hot-water or buffer tank to store surplus as heat. Vaillant lists Zerofy among the partners on its smart-interfaces page.

Zerofy connects the two: it reads TSUN production and controls your Vaillant heat pump to match, together with your other devices in one app, with dynamic tariffs and forecast-based Smart mode.

Setting up TSUN and Vaillant in Zerofy

1. Connect TSUN

Zerofy connects to the TSUN cloud with your TSUN Smart login and reads your inverter data.

1. Register your system in the TSUN Smart app.
2. In Zerofy, add an inverter, choose TSUN and log in with your TSUN Smart credentials.

Good to know: Only TSUN Smart accounts work (inverter IDs starting with Y); TSUN Home accounts are not supported. Battery and meter data are only partly available, depending on the system.

Step-by-step guide for TSUN

2. Connect Vaillant

Zerofy connects through Vaillant’s cloud using your internet gateway’s serial number and shows a Space Heating and a Hot Water Tank device; you can adjust room and flow temperature, and Autopilot triggers the hot-water boost.

1. Make sure the system runs on a supported gateway (myVAILLANT connect, sensoNET, eRELAX) and is online.
2. Copy the gateway serial number from the back of the gateway or from the myVAILLANT app under Status > Gateway.
3. In Zerofy, add a Vaillant device and enter the serial number.
4. Enable Autopilot (Solar or Smart mode) for the Hot Water Tank.

Good to know: The Vaillant integration is in beta. Supported controllers are eRELAX, E7C, VRT-350, VRC-720, VRC-710 and VRT-380; Autopilot currently steers only the hot-water tank, space-heating control is coming.

Step-by-step guide for Vaillant

3. Turn on Autopilot

In Zerofy, open your Vaillant heat pump, turn on Autopilot and choose Solar – or Smart to also use dynamic tariffs and forecasts. Set the priority, activation threshold and minimum runtime.

Dynamic tariffs

Zerofy can also run your Vaillant heat pump on dynamic electricity prices (EPEX Spot or Nord Pool, e.g. Tibber or aWATTar) or on a fixed time-of-use tariff. Smart mode combines those prices with forecasts of your household consumption and your TSUN solar production.

Learn more about Smart Mode

About TSUN and Vaillant

TSUN – TSUN (TSUNESS Co., Ltd., Suzhou, China, with a German office in Frankfurt) makes microinverters from 300 W single units to 3.3 kW 6-in-1 units. In Europe it is mainly found in 800 W balcony systems such as the TSOL-MS800, often combined with TSUN balcony storage (MSU2000, MSU4000Elite). Monitoring app: TSUN Smart.

Vaillant – Vaillant is a German heating manufacturer from Remscheid. Most homeowners have an aroTHERM air-to-water heat pump or an ecoTEC boiler, run by a sensoCOMFORT/multiMATIC controller (VRC 700/720) and connected to the internet with a myVAILLANT connect or sensoNET module. Products: aroTHERM plus, aroTHERM Split, flexoTHERM exclusive, flexoCOMPACT exclusive, recoCOMPACT exclusive, versoTHERM plus, ecoTEC boilers.

Manufacturer information last checked: October 2026.

All devices that work with TSUN