How well will a dehumidifier work in an unsealed room?

[pyite20v]

In a 4x8 tent for example, with a 8" inline fan exhaust, and 6" intake in. By my calculations the air is getting swaped out every minute or so, would the dehumidifier even have time to do anything, or would the slightly dryer processed air just get almost immediately replaced by new incoming air? This is in a very humid environment, and RH is getting up to 75-80% at night.

 

[kiwiboy]

I would say that the dehumidifier would be a great help when lights are out and the exhuast is off.

 

[compost]

any environmental controls are useless when your room air is exchanged that fast. I agree with kiwi, I would set it up so the exhaust shuts off at night and a dehumidifier kicks in.

 

[Che]

if the RH is coming from the plants, you would benefit from a larger exhaust fan. Like they said above, anytime the exhaust is off you should be running a dehu.
If it's your air supply coming in that contains high humidity, you might install the dehumidifier wherever your intake is to tackle it there..

 

[Ursus]

i have a similar question.. I have a sealed closet and am not able to modify the door or make any exhausts. I have one fan in the closet blowing on the tops. So i could really benefit from a dehumidifier?

 

[Lazyman]

Your intake and exhaust fans should always be hooked up to a thermostat, not a timer. That way they don't run uneccessarily, saving you power and noise, and keeping temps stable. Your dehuey will then have a chance to do some good.

 

[Guest 18340]

double post

 

[Guest 18340]

I would say that the dehumidifier would be a great help when lights are out and the exhuast is off.

any environmental controls are useless when your room air is exchanged that fast. I agree with kiwi, I would set it up so the exhaust shuts off at night and a dehumidifier kicks in.

Remember that a dehuey produces warm air.

 

[compost]

Your intake and exhaust fans should always be hooked up to a thermostat, not a timer. That way they don't run uneccessarily, saving you power and noise, and keeping temps stable. Your dehuey will then have a chance to do some good.

For room ventilation I agree in most situations, although there is always exceptions for different set ups in different environments.

i have a similar question.. I have a sealed closet and am not able to modify the door or make any exhausts. I have one fan in the closet blowing on the tops. So i could really benefit from a dehumidifier?

Depends on how well your room cools off at lights out Ursus. Its very true a humidifier will add temps to your room so you should have that in consideration so that your room doesn't overheat. My opinion that a dehumidifier will help is assuming that you have other environmental factors in check. No one would question the need to keep your RH levels down during flowering. However you must be able to keep other growth factors inline or you will not benefit from it.

 

[pyite20v]

I have to run an exhuast fan though becaus thats what scrubs the air. If I turn the exhaust off the stinky air will just seep out of the tent and thats no good.

So basically I need to run an exhuast fan 24-7. Should I not bother with a dehumidifier?

What about CO2?

 

[kiwiboy]

CO2 will be a waste of time with 24/7 exhuast.

Look at getting another carbon filter that only recirculates air in the growroom. Then put the exhuast on a thermstat. I recirculate filter will minimize the smell while the exhuast is off.

 

[gonzo`]

If your air is replaced every minute you will not have humidity problems will you?? When lights are off temps may be an issue (too low). Don't let temps fall below 70F for optimal growth..

 

[~Shhh~]

Hi,

I have tried putting my 35 pint (20 Liter) dehumidifier in a 4 x 8 tent to help with RH but it wasn't the best solution as I have 780m3 exhaust and 420m3 intake running 24/7 on thermostatic controller. Exhaust is never off as smell would be a security risk due to smells escpaing

Your problem is dual...

1) You have high incoming RH air being pumped into tent.
2) The plants are also increasing RH via transpiration.

As I only put it in a few weeks before the chop, I didn't try the following, but feel it would work better than the dehuey in tent due to amount of air exchange occuring in there.

Try running dehuey in the room the tent is set up in. Then use this dehumidified air as your intake air. It should in theory now be lower in humidity than your 75-80% RH air from outside once the dehuey has run for a few hours.

I intend to try this in a few weeks time when I reset my tent back up.

Pumping lower RH air into tent should lower the RH in there.

 

[foaf]

Ive had the same problem before, humid air supply and a dehumidifier that couldnt keep up with the air turnover except at night when the lights were out and fans off. If you dry it out very well for 12 hours, that is usually enough to fend off bud rot, even if it is too humid for the other 12 hours. Increasing circulation within the grow tent helps some just so that there arent pockets of extra high local environment humidity, like where buds touch the walls.

Also, I think my new GroZone exhaust controller will be helping out, it reduces the blowers output based on the temperature. If it is not too hot, the blower reduces its speed. Im not sure if its a variac or a triac, its all solid state, and it hasnt damaged my blowers yet and they dont hum badly like they have with one other speed controller I had. anyway, with the blowers on a lower speed some of the time, my dehumidifier is keeping up much better now. you can set a minimum idle speed too, so that you always have co2 turnover and always have odor control.