ASKOMA Askoheat+

Use cases

• Divert surplus PV production to hot water instead of exporting at low feed-in tariff rates.
• Build a ModbusCloud automation that reads a grid meter and writes Load Setpoint to the ASKOHEAT+ every few seconds for tight PV self-consumption.
• Log actual load over the day to quantify how much PV surplus was captured as heat.
• Alert the installer when emergency mode triggers, which usually means the buffer tank reached its temperature limit.
• Compare pre and post ASKOHEAT+ installation savings by tracking export reduction over time.

Installation

1. 1Enable Modbus TCP on the ASKOHEAT+ controller via the device configuration interface.
2. 2Connect the ASKOHEAT+ to the local LAN and note its IP address.
3. 3In ModbusCloud, add a Modbus TCP device at the ASKOHEAT+ IP, port 502, slave ID 1.
4. 4Import the ASKOMA Askoheat+ template. Readings appear immediately.
5. 5To use the internal autoregulator, write Load Feedin every few seconds from a ModbusCloud automation that polls your grid meter.

Things to watch for

01

Which do I use: Load Setpoint or Load Feedin?

Load Setpoint is the direct power target (you tell the ASKOHEAT+ how many watts to absorb). Load Feedin is the surplus power from the grid meter (you tell the ASKOHEAT+ how much PV is currently being exported). Pick one control strategy and stick with it.

02

Temperature at 325 reads strangely. Byte order?

Register 325 is float32 spanning two Modbus addresses. If the value is clearly wrong, try toggling the byte order in ModbusCloud device settings. The default is ABCD but some firmware revisions use CDAB.

Registers (7)

4 read / 3 write

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