humidity raises over 25% with lights off ?

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RootsRuler

RootsRuler

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benjones said:
if i can't get the RH down via AC or the dehumidifier i will add another fan , i have 2 big ones and 2 small ones already , 6 inch extraction and inlet fan
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IMO, for the size room you have that extraction fan seems awfully small. 25 meters square works out to 82sq/ft in yank measurements. If the room is square that means you have roughly a 20' x 20' room.

A 6" fan isn't going to move enough air in the room unless I'm missing something here. Assuming you have 8 ft ceilings, 20' x 20' x 8' would give you 3200 cubic feet of air you need to move. Even if your fan is moving 400 CFM it's going to take at least 8 minutes to exchange the air in your room.

IMO, a 10" or 12" fan would be more conducive to the air flow you need.
 
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elusiveshame

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benjones said:
i have 4 mars hydro fce4800 in a room about 25sq meters . the flow of air in and out is done but 2 6inch mars hydro fans
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benjones said:
My room is 3meters x 3 m X roughly 2.5 - 3 m height , I’ll have to measure.
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3x3 = 9 meters squared. 3x3x3 is 27 cubic meters.

RootsRuler said:
IMO, for the size room you have that extraction fan seems awfully small. 25 meters square works out to 82sq/ft in yank measurements. If the room is square that means you have roughly a 20' x 20' room.

A 6" fan isn't going to move enough air in the room unless I'm missing something here. Assuming you have 8 ft ceilings, 20' x 20' x 8' would give you 3200 cubic feet of air you need to move. Even if your fan is moving 400 CFM it's going to take at least 8 minutes to exchange the air in your room.

IMO, a 10" or 12" fan would be more conducive to the air flow you need.
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Going by his measurements, it would be about about a 10'x10'x10' (~9.8x9.8x9.8) room. So ~97 sq feet, or 290 cubic feet. A 20x20' foot room would be 400 sq feet :P

But you're right, a 6" fan won't help at all. He needs much bigger.
 
RootsRuler

RootsRuler

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elusiveshame said:
3x3 = 9 meters squared. 3x3x3 is 27 cubic meters.



Going by his measurements, it would be about about a 10'x10'x10' (~9.8x9.8x9.8) room. So ~97 sq feet, or 290 cubic feet. A 20x20' foot room would be 400 sq feet :P

But you're right, a 6" fan won't help at all. He needs much bigger.
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I think we're both wrong. 25 meters squared would be a room that is 5 meters by 5 meters right? If so then 5 meters is approximately 16 ft. 16 x 16 x 8 = 2,048 cu/ft

The recommended amount of air exchange is usually 3 -5 times per minute so he needs to exchange at least 6,000 cfm if my calculations are correct.
 
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elusiveshame

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RootsRuler said:
I think we're both wrong. 25 meters squared would be a room that is 5 meters by 5 meters right? If so then 5 meters is approximately 16 ft. 16 x 16 x 8 = 2,048 cu/ft

The recommended amount of air exchange is usually 3 -5 times per minute so he needs to exchange at least 6,000 cfm if my calculations are correct.
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He said 3 meters by 2.5-3 meters and about 3 meters tall in one of his earlier posts.

Regardless, he needs better air exchange :p
 
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benjones

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I will measure it accurately today and update you guys

My measurements were half guess work as each table is 2.18 m long

Thanks for you help
 
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benjones

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thanks @RootsRuler

i will go and measure now

Would I be better off for now to have both 6 inch fans extracting and nothing bring in fresh air except for what it pulls through the open door , until my bigger fan arrives ?

At the time I bought the fans 6 Inch was my only option as most stock had sold out . I kind of forgot about it after that .
 
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benjones

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The room is 3m x 3m floor space and 2.5 m in height . Do you think an 8inch will be ok or should I try to get a 10 inch
 
RootsRuler

RootsRuler

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benjones said:
thanks @RootsRuler

i will go and measure now

Would I be better off for now to have both 6 inch fans extracting and nothing bring in fresh air except for what it pulls through the open door , until my bigger fan arrives ?

At the time I bought the fans 6 Inch was my only option as most stock had sold out . I kind of forgot about it after that .
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That would probably be better but I think it's imperative that you measure all dimensions in the room so that you can figure out the cubic feet of air that you need to move before you order anything, then you can properly size the fan you need to be able to move the air needed.

Personally, I like AC Infinities line of fans and controllers. I can't tell you how much nicer it is not having to constantly be monitoring temp and humidity and having to manually adjust fan speed.
 
RootsRuler

RootsRuler

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benjones said:
The room is 3m x 3m floor space and 2.5 m in height . Do you think an 8inch will be ok or should I try to get a 10 inch
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10 inch would be the smallest I would even consider although I would feel more comfortable with a 12 or 14 inch. Before you do anything confirm my numbers with other more knowledgeable members just to make sure. Don't want to spend your money unneccessarily.

Do you know the CFM of the 6 inch fans you have? You may be able to get away with both of them exhausting.
 
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benjones

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RootsRuler said:
That would probably be better but I think it's imperative that you measure all dimensions in the room so that you can figure out the cubic feet of air that you need to move before you order anything, then you can properly size the fan you need to be able to move the air needed.

Personally, I like AC Infinities line of fans and controllers. I can't tell you how much nicer it is not having to constantly be monitoring temp and humidity and having to manually adjust fan speed.
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I will have a look to see if I can get them but my options are pretty limited here at the moment As to what I can buy
 
RootsRuler

RootsRuler

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benjones said:
402 CFM
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12" would be my choice but run the two 6" fans and see how you do. I have a 5' x 5' x 7'(1.5m x 1.5m x 2m)tent with a 6" ACI exhaust fan. The tent is 175 cu/ft. The ACI fan pulls 400 CFM. I'm exchanging air a little over twice a minute. I wish I had gone with ACI's 8" T8 fan and controller combo. the T8 does 807 CFM. At 800 CFM I'm getting almost 5 exchanges a minute.

Your room is twice the size of my tent.
 
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benjones

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RootsRuler said:
12" would be my choice but run the two 6" fans and see how you do. I have a 5' x 5' x 7'(1.5m x 1.5m x 2m)tent with a 6" ACI exhaust fan. The tent is 175 cu/ft. The ACI fan pulls 400 CFM. I'm exchanging air a little over twice a minute. I wish I had gone with ACI's 8" T8 fan and controller combo. the T8 does 807 CFM. At 800 CFM I'm getting almost 5 exchanges a minute.

Your room is twice the size of my tent.
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i might have to use either an 8 or 10 inch along with the 6 inch . there are 2 windows in the bathroom where i vent the old air out , a 12 inch might be to big . thanks for trying to help me @RootsRuler

my AC is always set at around 23 as i can't program it for different temps at different times, but from today i shall manually lower it to 18c for the night time when the lights are off, hopefully that helps a bit
 
RootsRuler

RootsRuler

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benjones said:
i might have to use either an 8 or 10 inch along with the 6 inch . there are 2 windows in the bathroom where i vent the old air out , a 12 inch might be to big . thanks for trying to help me @RootsRuler

my AC is always set at around 23 as i can't program it for different temps at different times, but from today i shall manually lower it to 18c for the night time when the lights are off, hopefully that helps a bit
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First try the ones you have in tandem before you spend any coin on a new fan. That may be enough air movement.
 
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