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

SET

You can set the fan speed with the command:

Byte index	Hex value – Meaning
0	44 – The command code.
1	00: Automatic. 01, 02: Low. 03, 04: Medium. 05, 06: High.

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

GET

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.

SET

You can set the fan speed with the command:

Byte index	Hex value – Meaning
0	44 – The command code.
1	00: Automatic. 01: Fan speed 1. 02: Fan speed 2. ... 06: Fan speed 6.

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

GET

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

This only reflects what's selectable through the device's buttons.

2.1. Fan type: 3-speed fan

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

SET

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.

GET

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

Description pending

3. ECM Fan Settings

The following commands are for advanced users only.

Use with great caution.

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.

SET

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.

GET

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

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

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

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

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).