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KolaKing
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I haven't read the entire thread but from what I can gather from the few posts I've read OP has plants in a closet and is having heat issues.
OP you mentioned you have a 4" intake fan? How large is the closet? 4" may not be enough.
I also read that the closet is in a room that is air conditioned. If possible use the fan as an exhaust fan, exhausting outside the lung room. When the fan is exhausting air it will also pull air from the lung room into your grow space to replace what you are removing so you not only are removing hot air but are bringing in cooler air to help in cooling down the space.
To properly size the fan to your grow space you want to figure out the cubic feet you have in your space first. For example, in a closet that is 4' x 4' x 8' you have 128 cubic feet of space. You want to exchange the entire volume of air in the space at least once every 3 minutes. More frequent air exchanges are even better but for a minimum fan size you'll need to find a fan that can move at minimum 42 cu/ft/min. Most 4" inlines will do around 200 cu/ft/min but that's at full speed. Again, grow space dimensions will dictate the size fan you will need.
In my own tent, 5' x 5', I've set my fan speed to run constantly at a minimum of 20% of max fan speed, I have a 6" ACI inline exhaust fan with controller so I can use setpoints to raise and lower the fan speed depending on environmental conditions. The fan maxes out at 402cu/ft/min. I've set it to minimum speed 2 which means the fan is pulling approximately 80 cu/ft/min. The tents cubic footprint is 150 cu/ft. meaning for minimum exchange I'll need 50 cu/ft/min. I could set it at speed 1 and still meet my minimum but having more frequent exchanges is always a good thing.
For lighting I use the square footage of the space and multiply it by 30w. Using a 4' x 4' x 8' closet as an example you would have 16 sq/ft of floor space. 16 x 30 = 480w. That is the size light you want to hang to be able to provide the high light intensity you'll need for the flowering stage.
One thing you can do to lower the heat in your space is turning down the light energy. If you have a light meter you can set your light to its lowest setting, then drop the light height to 12" above your canopy. Use your light meter to measure the amount of light energy it is putting out so you can adjust your light height. Be careful that the light fan(spread) isn't compromising the outer edges. There will be a drop but you can improve that drop by raising your lights to get better light fan across your canopy. Using a bar light type of light helps as that design keeps edge drop to a minimum. By using the height of your light rather than just using your dimmer to get the right amount of light will lower the amount of heat your light is giving off and will also save you money on your electric bill. It'll take a little bit of time to dial in the correct height vs dimmer position but once you do you should notice a drop in temperature in the space.
OP you mentioned you have a 4" intake fan? How large is the closet? 4" may not be enough.
I also read that the closet is in a room that is air conditioned. If possible use the fan as an exhaust fan, exhausting outside the lung room. When the fan is exhausting air it will also pull air from the lung room into your grow space to replace what you are removing so you not only are removing hot air but are bringing in cooler air to help in cooling down the space.
To properly size the fan to your grow space you want to figure out the cubic feet you have in your space first. For example, in a closet that is 4' x 4' x 8' you have 128 cubic feet of space. You want to exchange the entire volume of air in the space at least once every 3 minutes. More frequent air exchanges are even better but for a minimum fan size you'll need to find a fan that can move at minimum 42 cu/ft/min. Most 4" inlines will do around 200 cu/ft/min but that's at full speed. Again, grow space dimensions will dictate the size fan you will need.
In my own tent, 5' x 5', I've set my fan speed to run constantly at a minimum of 20% of max fan speed, I have a 6" ACI inline exhaust fan with controller so I can use setpoints to raise and lower the fan speed depending on environmental conditions. The fan maxes out at 402cu/ft/min. I've set it to minimum speed 2 which means the fan is pulling approximately 80 cu/ft/min. The tents cubic footprint is 150 cu/ft. meaning for minimum exchange I'll need 50 cu/ft/min. I could set it at speed 1 and still meet my minimum but having more frequent exchanges is always a good thing.
For lighting I use the square footage of the space and multiply it by 30w. Using a 4' x 4' x 8' closet as an example you would have 16 sq/ft of floor space. 16 x 30 = 480w. That is the size light you want to hang to be able to provide the high light intensity you'll need for the flowering stage.
One thing you can do to lower the heat in your space is turning down the light energy. If you have a light meter you can set your light to its lowest setting, then drop the light height to 12" above your canopy. Use your light meter to measure the amount of light energy it is putting out so you can adjust your light height. Be careful that the light fan(spread) isn't compromising the outer edges. There will be a drop but you can improve that drop by raising your lights to get better light fan across your canopy. Using a bar light type of light helps as that design keeps edge drop to a minimum. By using the height of your light rather than just using your dimmer to get the right amount of light will lower the amount of heat your light is giving off and will also save you money on your electric bill. It'll take a little bit of time to dial in the correct height vs dimmer position but once you do you should notice a drop in temperature in the space.