Solarman + CTA

What Zerofy can do with Solarman 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. A Solarman balcony system covers only a small part of that, a rooftop system (Solarman systems range up to 12 kW) much more on sunny days.
• Zerofy gets new Solarman data every 5 minutes. Heat pumps shouldn’t switch often, so set a minimum runtime in Autopilot.
• 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 Solarman and CTA offer on their own

Solarman: Solarman offers no heat pump or SG Ready control.

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 Solarman 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 Solarman and CTA in Zerofy

1. Connect Solarman

Zerofy connects to SOLARMAN Smart with your account login and reads PV production, meter (consumption) and battery data of your plant; a Solarman P1 meter reader can also be added as a separate electricity meter.

1. Make sure your logger is online and your plant is set up in SOLARMAN Smart.
2. In Zerofy, add an inverter, choose Solarman and log in with your SOLARMAN Smart e-mail and password.
3. Optional: if the plant has a P1 meter, add it in meter setup under Solarman and select it from the discovered devices.

Good to know: Zerofy finds devices per plant, so a P1 meter must be assigned to a plant in SOLARMAN Smart. If a plant has both an inverter and a P1 meter, Zerofy offers two meters with the same plant-level values; connect only one of them.

Step-by-step guide for Solarman

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 Solarman solar production.

Learn more about Smart Mode

About Solarman and CTA

Solarman – Solarman (IGEN Tech, Wuxi, China) does not make inverters: it makes data loggers such as the LSW-3 Wi-Fi stick and runs the SOLARMAN Smart platform, which according to IGEN works with about 200 inverter brands, including Deye. If your inverter’s app is SOLARMAN Smart, your data comes through Solarman whatever brand is on the inverter. Monitoring app: SOLARMAN Smart.

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 Solarman