For the complete documentation index, see llms.txt. This page is also available as Markdown.

Fan Settings

1. Changing the fan speed

If the fan speed is set to auto, the actual speed is determined by an algorithm explained here. It's also reported in the keepalive of the device.

1.1 Fan type: 3-speed fan

You can set the fan speed with the command:

Byte index

Hex value – Meaning

0

44 – The command code.

1

00: Automatic. Default 01, 02: Low. 03, 04: Medium. 05, 06: High.

Example command: 0x4402 – Sets fan speed to Low.

You can get the fan speed with the command. The keepalive data in the example below is omitted for clarity.

Byte index

Sent request

Received response

0

45 – Command code

45 – Command code.

1

00: Fan speed is automatic. 02: Fan speed is Low. 04: Fan speed is Medium. 06: Fan speed is High.

Example command: 0x45;

Example response: 0x4502 – Fan speed is set to Low.

1.2 Fan type: ECM fan

You can change the fan speed with the following command set.

You can set the fan speed with the command:

Byte index

Hex value – Meaning

0

44 – The command code.

1

00: Automatic. Default 01: Fan speed 1. 02: Fan speed 2.

... 06: Fan speed 6.

Example downlink: 0x4404 – Sets the fan speed 4.

This command gets the ECM fan speed. The keepalive data in the example below is omitted for clarity.

Byte index

Sent request

Received response

0

45 – Command code

45 – Command code.

1

00: Automatic. 01: Fan speed 1. 02: Fan speed 2.

... 06: Fan speed 6.

Example downlink sent by the server: 0x45;

Example command: 0x4504 – The fan speed is 4.

2. Limiting the selectable fan speed

2.1. Fan type: 3-speed fan

You can change the fan speed limit with the following set of commands.

You can set the fan speed limit with the command:

Byte index

Hex value – Meaning

0

46 – The command code.

1

00: Low / Medium / High. Default value. 01: Low / Medium. 02: Low. 03: Fan control deactivated.

Example downlink: 0x4601 – Sets the fan speed limit to Low / Medium.

This command gets the target temperature. The keepalive data in the example below is omitted for clarity.

Byte index

Sent request

Received response

0

47 – Command code

47 – Command code.

1

XX - Fan speed limit value.

Example downlink sent by the server: 0x47;

Example command: 0x4701 – The fan speed limit is Low / Medium.

2.2 Fan type: ECM fan

3. ECM Fan Settings

3.1. ECM Fan min/max control voltage settings.

You can change the minimum and maximum voltage of the ECM fan with the following set of commands.

The command adjusts the voltage range of the ECM fan.

Byte index

Hex value – Meaning

0

48 – The command code.

1

XX - Vmin[V] * 10. Default value: 0x1E (3V).

2

XX - Vmax[V] * 10. Default value: 0x64 (10V).

Example downlink: 0x481947;

Sets the Vmin = 2,5V => 2,5 * 10 = 25 convert to HEX 0x19.

Sets the Vmax = 7,1V => 7,1 * 10 = 71 convert to HEX 0x47.

The command extracts the voltage range of the ECM fan.

Byte index

Sent request

Received response

0

49 – Command code

49 – Command code

1

XX - Vmin[V] * 10.

2

XX - Vmax[V] * 10.

Vmin/max[V] = XX / 10;

Example downlink sent by the server: 0x49;

Example command: 0x491947;

0x19 convert to DEC 25 => Vmin = 25 / 10 = 2,5V.

0x47 convert to DEC 71 => Vmax = 71 / 10 = 7,1V.

Adjustable range is 0…10V (0,1V resolution).

3.2. ECM Relay (F-ON)

This commands allow you to set/get the ECM relay (F-ON) - whether it's activated or deactivated at all.

Set the ECM relay to activated/deactivated.

Byte index

Hex value – Meaning

0

4C – The command code.

1

00: Deactivated the ECM relay (F-ON);

01: Activated the ECM relay (F-ON). Default state.

Example downlink: 0x4C01 – Activated the ECM relay (F-ON).

Get the status of the ECM relay.

Byte index

Sent request

Received response

0

4D – Command code

4D – Command code

1

00: The ECM relay (F-ON) is deactivated. 01: The ECM relay (F-ON) is activated.

Example downlink sent by the server: 0x4D;

Example command response: 0x4D01 – The ECM relay (F-ON) is activated.

3.3. ECM start up time

The ECM fan starts at maximum speed for a specified start up time.

Set up the start up time.

Byte index

Hex value – Meaning

0

4A – The command code.

1

XX - ECM start up time. Default value: 0x00 (The function is deactivated).

Example downlink: 0x4A03 - Sets the ECM start up time to 3 seconds.

Get up the the start up time.

Byte index

Sent request

Received response

0

4B – Command code

4B – Command code

1

XX - ECM start up time.

Example downlink sent by the server: 0x4B;

Example command response: 0x4B03 – The ECM start up time is 3 seconds.

Acceptable values: 0...20 seconds (1sec. resolution).

3.4. Additional fan modes

These commands are available for devices with firmware version ≥ 1.6

Set аdditional fan modes.

Byte index

Hex value – Meaning

0

7A – The command code.

1

00: Turn off the fan when the target temperature is reached. Default. 01: Keep the fan running for some time after reaching the target temp. 02: The fan runs continuously.

Example downlink: 0x7A02 - Sets the fan runs continuously.

Get аdditional fan modes.

Byte index

Sent request

Received response

0

7B – Command code

7B – Command code

1

XX - Additional fan mode.

Example downlink sent by the server: 0x7B;

Example command response: 0x7B02 – The fan runs continuously.

3.5. Fan off delay time

These commands are available for devices with firmware version ≥ 1.6

Continue running for X minutes on LOW speed fan to cool off the heating element.

Set up the start up time.

Byte index

Hex value – Meaning

0

78 – The command code.

1

XX - Fan off delay time. Default value: 0x01 (1min).

Example downlink: 0x7803 - Sets the fan off delay time to 3 minutes.

Get up the the start up time.

Byte index

Sent request

Received response

0

79 – Command code

79 – Command code

1

XX - Fan off delay time.

Example downlink sent by the server: 0x79;

Example command response: 0x7903 – The fan off delay time is 3 minutes.

Acceptable values: 1...255 minutes (1min. resolution).

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