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Marc-Olivier Arsenault edited this page Dec 13, 2022 · 7 revisions

Usage (Without Web UI)

Tefnut is 100% usable without WebUI. In theory it is 100% self sufficient. That being said if you want to monitor usage of it, you can use the WebUI or the Grafana Dashboard

Operation

Mode

In the setting file, you need to configure mode, the 3 options are "AUTO", "MANUAL" and "OFF".

  • AUTO: will use the temperature service to adjust the humidity level with outside temperature. (See table below). In the case they loose connection to the temperature service, they will default to the emergency_target
  • MANUAL: This will aim for the manual_target and try to keep humidity as close as possible
  • OFF This will never turn off the humidifier

Temperature to Humidity table

Outside Temp (oC) Target Humidity Level
<= -30 15%
<= -25 20%
<= -20 25%
<= -15 30%
<= -10 35%
<= 5 40%
> 5 45%

Deadband

To prevent Humidifier to constantly start and stop we use a deadband, in other word if the Desired Humidity level is 35% and the Deadband is 2. Tefnut will start the Humidifier 2% dryer and will stop it 2% more humid. E.g. Start at 32 (35-2) and stop it at 38 (35+2) (there is an overlap of 1 on each side, because we want the value to be outside of the range).

humidifier

Set stub for testing or cloud usage and pi to use with the Raspberry pi implementation

rpi_pi

BCM pin of the RPi to configure and use for the Humidifier.

auto_delta

When in Automatic mode, we follow the table (temperature -> humidity) to decide what is the target humidity level. Auto_delta does modify the output of this funtion. e.g. If it is 0degree celsius outside, the auto algorithm will return 40% as a target humidity. If we have a delta of -3, the target humidity level will be 37%.

Delays

Tefnut run on a 1 min loop (every min the control loop runs, to validate state of the Humidification, take any action and refresh data point). For performance reason, Ecobee humidity is only refreshed every 10 min and Temperature information every 15 minutes.

Usage (With Web UI)

The webpage is available on port 5000. So you can access it using http://IP.OF.YOUR.PI:5000

There is a webpage available to control Tefnut. It allows you to set Tefnut as:

  • Automatic: Use outdoor temperature to set the desire humidity
  • Manual: Use a fix target humidity level
  • Off: Humidifier, don't start

And set a desire Humidity Level, for Manual mode only, (Value between 10 and 50)

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