Mithrandir schreef op vrijdag 13 maart 2026 @ 15:10:
Ik ben bezig met controller software om de Openair + valves aan te sturen. Het idee is als volgt:
De OpenAIR controller pollt elke 60 seconden de CO2- en luchtvochtigheidswaarden van alle kleppen via HTTP. Op basis van deze sensorwaarden berekent hij per klep een "demand" (0-1): hoe ver de meetwaarde afwijkt van het doel (bijv. CO2 600→1500 ppm schaalt van 0 naar 1). De hoogste demand bepaalt de ventilatorsnelheid.
Elke klep leest elke 60 sec zijn eigen sensoren én de huidige ventilatorsnelheid van de OpenAIR controller. Door zijn eigen demand te delen door de genormaliseerde ventilatorsnelheid bepaalt de klep hoe ver hij open moet staan. Als deze kamer de ventilator aandrijft (hoge CO2), blijft de klep wijd open. Als een andere kamer de reden is dat de ventilator hard draait, gaat de klep juist verder dicht — zo wordt de luchtstroom automatisch naar de kamer geleid die het hardst nodig heeft. Kleppen blijven altijd minimaal ~5% open zodat de sensoren verse lucht meten.
Het systeem werkt volledig zonder Home Assistant. De communicatie is puur HTTP GET in beide richtingen: de controller leest sensorwaarden van de kleppen, en de kleppen lezen de ventilatorsnelheid van de controller. Als een apparaat onbereikbaar is, valt het terug op veilige standaardwaarden (lage ventilatie, kleppen open).
Very interesting, structured and documented project that complements and adds to the initial hardware project an integrated management.
There are obviously many ways to manage a VMC, depending on the hardware everyone has, valves, internal / external sensors, home automation,... That said, being able to have a relatively standard and adapted software configuration is a real plus for the entire project.
I hope that this initiative that starts well will continue to evolve towards a collaborative solution allowing future adjustments, additions, where any ideas are welcome, I am thinking in particular of taking into account sensors external to the valves (Air Sense pro in particular)
Although personally having a Duco set, I recently installed a VMC Renson Healthbox 3 at a friend's house (model imposed by the architect) its automatic operation is quite close to that proposed by Mithrandir, the ventilation runs constantly (sensors integrated into the valves oblige) at about 420 RPM a flow at 40M3/H while the motorized valves have a flow rate of 10% as long as the RH/CO2/COV rates are below the trigger threshold, and go to 100% directly into ace of exceeding the threshold to return quickly enough to the norm.
The ventilation power is obviously a function of the number of areas requiring 100% flow, but remains relatively constant.
In addition, this Box has a pressure sensor that allows automatic calibration of the installation, this process tests each zone one after the other, the motor probably rises to 100%, all the valves are closed except the one being tested which opens at 100% this allows the plant to determine the load of the line in each zone and probably determine the standby and operating power in load when the different parts associations require it.
A Renson API allows me to monitor this box via Home Assistant, this means that if you want to receive the logs from the power plant or valves, I can reasonably provide you with the .CSV files. Corresponding this can possibly be used to determine how a commercial product is managed independently.
Nice evening to all without forgetting a little wink to our friend The Flamingo
BR
Didier