Humidity will not go up! WTF

I cannot get my humidity above 30 RH. I have an evaporative warm mist humidifier in my room (12×5×7H) approximately. I have a high output 4 inch exhaust fan that I would rather not turn off. Heat is forced hot air as well as a small 250 watt portable heater temp maintains around 77F. I'm guessing the fans are sucking out all the humid air. So I imaging managing the exhaust fans is the key. Thanks

Forced hot air sucks. My old house had it and it was the same situation.
I added a honeywell whole house humidifier to the heating system and it made a huge difference. House seemed warmer with the added humidity as well.
Installation was easy, just a hole in the output duct and a 1/4" water line to the unit. Just needs to be tied into the heat system wiring for on and off.

Have you tried a bucket of water with a towel hanging out

Nope_49595933949 said:

Have you tried a bucket of water with a towel hanging out

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Yep. if the space is small enough strategically placed pans of water work great.

I'd explore your exhaust fan setting options. Sounds like you're pulling out humidified air too quickly.

Smokesteve said:

I cannot get my humidity above 30 RH. I have an evaporative warm mist humidifier in my room (12×5×7H) approximately. I have a high output 4 inch exhaust fan that I would rather not turn off. Heat is forced hot air as well as a small 250 watt portable heater temp maintains around 77F. I'm guessing the fans are sucking out all the humid air. So I imaging managing the exhaust fans is the key. Thanks

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I have about the same sized room and still have to run a dehumidifier all year round. Grow bigger plants, or add more.

Any pics of your set up?

If they are just seedlings in that sized room I’d suggest using a smaller space until the plants have actual biomass that’s transpiring.

I have a little bigger than that room that the main house heater runs through sometimes it’s hard to maintain the right humidity but never that low maybe like 55 for me is the lowest it’ll go. I just added a extra warm air humidifier now it stays whatever I want it to be right now it’s 75% make sure you humidifier is as far away from your room exhaust as possible and away from fans. Thinking your spreading the air better with a fan is actually you cooling the air quicker and preventing a even moisture spread.

If your room isn’t sealed it’ll level off on whatever the outer rooms humidity is or atleast try and equal that difference so make sure everything is extra sealed and your only air flows are room inlet and exhaust.

Try oil filled rads instead of forced air.
Slow your fan down.

I always have to run a swamp cooler during early veg. They put out A LOT of humidity. Mist humidifiers tend to clog up air filters, and leave a fine powder film on everything. Not really sure how small of a unit you could get, but they work really well. Mines a Portacool, and pumps out a few gallons of humidity a day.

DoubleAtotheRON said:

I always have to run a swamp cooler during early veg. They put out A LOT of humidity. Mist humidifiers tend to clog up air filters, and leave a fine powder film on everything. Not really sure how small of a unit you could get, but they work really well. Mines a Portacool, and pumps out a few gallons of humidity a day.

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Have to used distilled water. The powder is the mineral content of the water.

Nope_49595933949 said:

Have you tried a bucket of water with a towel hanging out

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Better a drying rack hang some towels and let the tips suck up the water.
You can put a fan next to it let it blow between your ''fins''

Look into doing a sealed grow, sounds like your just venting out the moist air and wasting your time & money running a humidifier.

Dreaming1 said:

Have to used distilled water. The powder is the mineral content of the water.

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True.

Okay this evening I'm going to shut off the exhaust fan and block it off. Then I'll monitor it to see how high I can get it to go that will be good info to start with.

Some kind of fan speed control may be helpful if there's one your fan will work with. Otherwise you could look at a timer that allows it to turn on/off in intervals or trigger it on or off based on humidity levels.

Smokesteve said:

Okay this evening I'm going to shut off the exhaust fan and block it off. Then I'll monitor it to see how high I can get it to go that will be good info to start with.

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If anything carefully watch to make sure your humidity doesn't get too high when you cut off the exhaust. I'd love to have a dry grow space, I had to spend over $3,000 on dehumidifiers just to grow in the space I have.

Actually, there's a much simpler way. If you have good ventilation and your pots have drainage material in them,
just leave the runoff in the coasters or clean them out and fill em with water a bit.
I just remembered I always had high RH when I didn't take out the runoff.

A: your plants will surely dry out slower
B: your RH should go up

no?

Cheers

^^ If you're going to do that, make sure your pots or your cloth bags are not sitting in the runoff, but raised above that.

Smokesteve said:

I cannot get my humidity above 30 RH. I have an evaporative warm mist humidifier in my room (12×5×7H) approximately. I have a high output 4 inch exhaust fan that I would rather not turn off. Heat is forced hot air as well as a small 250 watt portable heater temp maintains around 77F. I'm guessing the fans are sucking out all the humid air. So I imaging managing the exhaust fans is the key. Thanks

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Your exhaust fan seems tiny for your grow. I used a 6" inline for my 2x2 and 3x3.
For controls, my inkbird exhausts at 79ish degrees just to keep humidity close to the right range. At lights off i switch my sensor to humidity at 50% to prevent rain in the tent.