Huawei + CTA

What Zerofy can do with Huawei and CTA

In practice

• When there’s enough surplus, Zerofy switches the relay and the heat pump receives the SG Ready signal. How it reacts – for example by heating the hot-water tank to a higher temperature – is set in the heat pump’s own controller.
• A heat pump draws roughly 1–3 kW while running, which a typical Huawei home system (2–10 kW) can cover on sunny days.
• Zerofy gets new Huawei data every 5 minutes. Heat pumps shouldn’t switch often, so set a minimum runtime in Autopilot.
• Zerofy also shows your Huawei battery, so you can see whether surplus goes into the battery or into the heat pump.
• CTA’s own tip for SG Ready operation: if rooms get too warm or too cold, change the upper temperature limit by 1 °C at a time and leave it for one to two days before adjusting again; agree the values with your heating installer.

What Huawei and CTA offer on their own

Huawei: The SmartAssistant (EMMA) switches one SG Ready heat pump directly through its DO dry contacts or an external relay, and a second one through a Shelly. It also controls Vaillant aroTHERM plus via EEBUS and the Askoheat+ heating rod via Modbus TCP.

CTA: For PV self-consumption, CTA connects its heat pumps to external energy management systems via a PV input, SG Ready or Modbus (Optiheat and Aeroheat). CTA publishes SG Ready instructions per model and a compatibility list for the Swiss Solar Manager gateway (Modbus TCP/RTU).

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

Setting up Huawei and CTA in Zerofy

1. Connect Huawei

Zerofy connects to Huawei FusionSolar with the login of a FusionSolar owner account; the older Northbound API account still works as a legacy option.

1. Check that your FusionSolar account has a verified email address (System → Personal Settings).
2. Make sure it is an Owner account; if you only have an installer or company account, invite a new user with the role Owner in the FusionSolar app.
3. Add Huawei FusionSolar in Zerofy, choose the FusionSolar login and enter the owner account’s credentials.

Good to know: Installer and company accounts don’t work, and the owner invitation can only be sent from the FusionSolar smartphone app, not the web portal. If you use the legacy Northbound API, create a dedicated account for Zerofy, because sharing it with other services can cause data gaps.

Step-by-step guide for Huawei

2. Connect CTA

The Zerofy docs have no CTA-specific guide; the documented way to control a CTA heat pump is Zerofy’s SG Ready integration, with a smart relay such as a Shelly wired to the heat pump’s SG Ready inputs.

1. Check in CTA’s SG Ready compatibility list that your model and controller (Optiplus, Optiplus 3, Aeroplus 2.0/2.1) are listed.
2. Have an electrician wire a smart relay (e.g. Shelly) to the heat pump’s SG Ready inputs.
3. Add the relay to Zerofy and configure it as SG Ready controller.

Good to know: CTA marks Optiheat Inverta units and several Aeroheat models as needing a software or controller update for SG Ready. For older or unlisted units, CTA says integration can mean extra cost, e.g. a controller replacement.

Step-by-step guide for CTA

3. Turn on Autopilot

In Zerofy, open your CTA 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 CTA 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 Huawei solar production.

Learn more about Smart Mode

About Huawei and CTA

Huawei – Chinese manufacturer (Huawei Digital Power, Shenzhen). Homes typically have a SUN2000 hybrid inverter, either the single-phase L1 (2–6 kW) or the three-phase M1 (3–10 kW), with a LUNA2000 battery, plus optional optimizers and the SmartGuard backup box. Monitoring app: Huawei FusionSolar.

CTA – CTA AG is a Swiss manufacturer of heat pumps and cooling machines, with production at its headquarters in Münsingen near Bern. Its home range covers Optiheat ground-source and water-source heat pumps and Aeroheat air-source heat pumps. Products: Optiheat (brine/water and water/water), Optiheat Inverta, Aeroheat (air/water, indoor and outdoor units), Aeroheat Inverta.

Manufacturer information last checked: October 2026.

All devices that work with Huawei