VPD as a range for temp &/or RH

Hi Guys

I was wondering if you could incorporate VPD in your programming. I mean truly use it in the calculations.

Currently, if you input a VPD and a temp or RH the program will calculate a corresponding RH or temp and locks it into that point. When the daytime setting engages the heater engages and the temp rapidly rises until the heat from the lights over powers everything and we go into cooling mode. From there it is a battle to keep it at that point.

What would be ideal is to input a VPD and a range of temp &/or RH. This way when the morning comes the Niwa controller will gently push the temp/RH into the range and keep it there. Later in the day if conditions warrant (ie there is a heat dome) the system will kick in to maintain the VPD at the upper range.


Hey Skeena, thanks for your feedback, we will take it into account.

I second this feature.

For some reason I thought it worked like this when I purchased the unit.

Maybe I am going about it the wrong way, but I am having trouble making all 4 units work efficiently together. (Humidifier, Dehumidifier, Heater, AC)

I would LOVE to have an option where VPD takes precedence over temp and relative humidity.

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New to indoor growing, I don’t have the luxury of an AC and have been consistently fighting it for a couple of years. If there was an option, let’s say that if the AC was not a select device, follow the VPD when temps exceed the set program until the programmed heat temps return.