Run it constantly, and just adjust it as needed. It's gonna be needed to get the heat out of there. I keep mine on hi in a 2x4 195cfm with a vent open on the bottom for passive intake. I run 211w of LED and temps hovering in 79-82F RH 40% in late flower. I will be running my AC in the room with all vents open to cool the tent down dramatically before chop. I like the cool temp colors.
What about if you had to add heat into the room? Would you keep the exhaust on through out the whole night? Or maybe vent once an hour?
i'm waiting on a trolmaster fan controller. i also got a temp controller that i will be plugging a ceramic heater into to regulate temp
My apologies, I was asking @Renfro a hypothetical question. Trying to figure out my ventilation also.
me, personally, have been venting 24/7, and have used a heater by one of my passive intakes and once the temp goes up, it does a decent job of retaining a little warmth. but i feel like my fan is too efficient, so i'm going to slow it down with a fan controller. then a controller with the heater plugged in and a humidity controller to keep my RH% right.
have you tried a dehumidifier? heaters also dry out the air a bit.
Humidity can be hard to control if everything isn't dialed in, including outside temps & humidity. If your room is humid, and you run an intake you are adding to the tents humidity. Run a small radiator in the tent with a cheap thermostat keeping it around 77 day/68 nights. Then running the intake/extract will suck the humid air out. Just have to set the temp and fans dead correct.
Having to sacrifice heat for humidity isn't unusual, for the last 4 weeks my room has barely been above 24c and that's with a dehumidifier running, when the light out the dehumidifier + constant slow extraction maintains around 60%/20c its the outside rh that decides the final figure usually 48/60%.
How big is the room? And how big a room can dehumidifiers do? How much water do you use each watering?
Do what is required to keep the humidity from creeping up. You don't have to ventilate all night persay, you could use a humidistat. You could use a dehumidifier, that adds heat and dehumidifies. Adding heat is good for humidity as warmer air holds more water. So if you warm the room the RH% drops. Basically if the RH% doesn't rise without venting then you don't need to vent/dehumidify however that is rarely the case. In some cases venting could make the RH% problem worse if you have high ambient RH%
Ive done it a lot, aside from condensation on the duct / blower it's not an issue unless the air is blowing directly on your plants. I blow the air in up high so it mixes with hot air. The cold air will be dry air so thats good, even if it's 100% RH outside, warm that air up and it's negligible water content drops your RH%.