SAJ + Daikin

What Zerofy can do with SAJ and Daikin

In practice

• Hot water is the simplest heat store: Autopilot can raise the hot-water temperature of your Daikin heat pump in hours with surplus.
• Zerofy can also change the room temperature and flow temperature of your Daikin heat pump, so space heating can shift into sunny hours.
• A heat pump draws roughly 1–3 kW while running, which a typical SAJ home system (3–10 kW) can cover on sunny days.
• Zerofy gets new SAJ data every 5 minutes. Heat pumps shouldn’t switch often, so set a minimum runtime in Autopilot.
• Zerofy also shows your SAJ battery, so you can see whether surplus goes into the battery or into the heat pump.
• Check how your installer set up the flow temperature: with a weather-dependent curve, Onecta only allows shifting the curve with an offset, not setting a fixed leaving-water temperature. Raising the hot-water setpoint during surplus is usually the simplest way to store solar heat.

What SAJ and Daikin offer on their own

SAJ: The SAJ eManager has two dry-contact (DO) outputs for a heat pump, switched by tasks you set up in the app. SAJ says Elekeeper supports heat pumps and water heaters but doesn’t list compatible models.

Daikin: Altherma units have Smart Grid inputs driven by an inverter or energy manager: in “Recommended ON” the heat pump buffers PV power in the hot-water tank (optionally also in the rooms) and limits its power consumption, statically or dynamically from a pulse meter at the grid connection. With the BRP069A61 LAN adapter the meter must measure the net feed-in at a single grid connection point.

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

Setting up SAJ and Daikin in Zerofy

1. Connect SAJ

Zerofy reads your plant from the SAJ cloud: you add Zerofy as a developer in the Elekeeper app and then enter your Plant ID in Zerofy.

1. In the Elekeeper app, tap ••• and open Plant Management.
2. Under Developer/Partner, paste the Developer ID shown in Zerofy and confirm access.
3. Copy your Plant ID from Plant Management and paste it into Zerofy.

Good to know: How fresh the data is depends on how often the SAJ cloud updates. For the battery, Zerofy supports forced charging but not switching the battery mode.

Step-by-step guide for SAJ

2. Connect Daikin

Zerofy connects to the Daikin Onecta cloud with your Onecta login and can set room temperature, leaving-water (flow) temperature and hot-water temperature; Autopilot runs it on solar surplus or low prices.

1. Register the heat pump or air conditioner in the Daikin Onecta app and check it is online.
2. In Zerofy, add Daikin and log in with your Onecta credentials.
3. Enable Autopilot (Solar or Smart mode) for the device.

Step-by-step guide for Daikin

3. Turn on Autopilot

In Zerofy, open your Daikin 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 Daikin 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 SAJ solar production.

Learn more about Smart Mode

About SAJ and Daikin

SAJ – SAJ (Guangzhou Sanjing Electric) is an inverter maker from Guangzhou, China. Homes usually have the H2 hybrid inverter with B2 battery or the HS2, HS3 or AS2 all-in-one storage systems; the eManager unit and the Caro wallbox tie them together. Monitoring app: Elekeeper.

Daikin – Daikin is a Japanese air-conditioning and heat pump maker with its European headquarters in Belgium. Homeowners typically have an Altherma 3 air-to-water heat pump or Daikin split air conditioners, both connected through the Daikin Onecta app. Products: Altherma 3 R, Altherma 3 H HT, Altherma 3 M, Altherma 3 GEO, split air conditioners in the Onecta app.

Manufacturer information last checked: October 2026.

All devices that work with SAJ