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Intake fan/fresh air

HaanfSolostarted grow question 12d ago

I’ve added an intake fan/duct that is pulling fresh air from outside into the tent. 1. will that help regulate RH and temp? 2. should I have it run all day on low or plug it into a timer and have it turn on/off every X amount of hours?

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m0useanswered grow question 12d ago

1. will that help regulate RH and temp? Maybe?? depends what the RH and temp of the air its pulling in is.... eg. if outside is hot and humid. it not going to magicly lower the RH and temps. If the air is cooler and less humid then yes it will help lower it. 2. should I have it run all day on low or plug it into a timer and have it turn on/off every X amount of hours? All depends how you set it up, My system is set to a minium speed and then I have alarms when it gets to hot or RH goes to high then the fans turn on high but thats rare it happens and I just edit the base rate of exchange from 3-4-5 on a scale of 1-10. Ideally you want to have constant airflow for the plants to grow big.

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Mr_Borisanswered grow question 12d ago

Yes your RH will increase and temperature will drop. Your lights actually burn the humidity out of the air so you need to pull in fresh air. Keep it running 24/7

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Organomananswered grow question 12d ago

Run all the time.

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Ultravioletanswered grow question 12d ago

Generally you want to optimize VPD for daytime, so you naturally want the RH to be high, so long as you match the temps all you need is a gentle passive intake for daytime. 4" intake on all night , with 6/8" exhaust, variable speed preferred, link exhaust to RH% overnight. Adding an intake fan pulling fresh air from outside will help regulate the temperature and relative humidity (RH) inside your grow tent, but its effectiveness depends on the outside air conditions. This is because the fresh air you pull in will mix with the stale, hot, and humid air from your plants' transpiration, which your exhaust fan is removing. For the best results, your exhaust fan should be slightly more powerful than your intake fan, or set to a higher speed. This will make the tent walls bow inward slightly, ensuring that fresh air is consistently drawn in and odor is contained. An ideal ventilation system exchanges all of the air inside the tent every 1 to 3 minutes, I prefer to link it to RH% once the canopy gets big.

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00110001001001111Oanswered grow question 12d ago

depends on ambient temp and RH... is it cooler and lower rh where the air is pulled from? if yes, it'll help. moving air around does not heat or cool it nor reduce or raise RH% ('relative' so temp changes does change with temp changes)... Unless you are adding co2, you should leave it running 24/7. The plant transpires.. uses up co2 and it'll need to be refreshed. if stink is an issue, a filter and a little negative pressure can contain it. (tent walls bow in if there is negative pressure... only needs to be minimal to be functional in that regard)

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