Could someone help mini split.

[Dankdad64]

I have a 8 x 8 room almost 9 ft ceiling. I have 7980 watts of equipment lights,fans intake ect. I want to put in a mini split 9000 BTU. Will this work?

 

[Travis Kelcee]

Yes it will work fine.

I have installed 2 mini splits if you have any questions.

 

[Dankdad64]

Yes it will work fine.

I have installed 2 mini splits if you have any questions.

Thank you , I thought it would but people were tell me 9000 was to big for that small of a area.

 

[Dankdad64]

Thank you , I thought it would but people were tell me 9000 was to big for that small of a area.

Here what they are saying

 

[Ca++]

About 2000-2500w of cooling.
I don't really know what you are cooling, as you have unknown extract, and unknown air qualities coming in. I have your power use, but the split isn't the only player. I think we must be fighting the weather.

 

[flylowgethigh]

Does it have a duct to send the hot air elsewhere?

 

[Dankdad64]

Does it have a duct to send the hot air elsewhere?

Yes to the out side

 

[Dankdad64]

About 2000-2500w of cooling.
I don't really know what you are cooling, as you have unknown extract, and unknown air qualities coming in. I have your power use, but the split isn't the only player. I think we must be fighting the weather.

Filtered air from garage that gets enough outside air.

 

[Dankdad64]

Yes to the out side

6 in intake. 8 in exhaust on controller the turns on and off at set temperature fully controllable

 

[Travis Kelcee]

About 2000-2500w of cooling.
I don't really know what you are cooling, as you have unknown extract, and unknown air qualities coming in. I have your power use, but the split isn't the only player. I think we must be fighting the weather.

My 12k maxes out at 1600 watts for heat and 1400 watts for cooling according to the specs.

 

[Travis Kelcee]

Here what they are saying

They don't run constantly. You set the temp like you would with central air.

It might be over sized for your space but that only means it will burn less juice and not have to run that often.

 

[Ca++]

My 12k maxes out at 1600 watts for heat and 1400 watts for cooling according to the specs.

Your 12000btu unit consumes up to 1400w from the wall, shifting 3500w outside. It also works as a heat pump, reversing this, but is not quite so efficient. Or just maybe it's not a heat pump, and is just a heater. Using the defrost function.

 

[Ca++]

Filtered air from garage that gets enough outside air.

I would need the actual measured volume of air coming though, in something like m3/h. Along with the temp it is, and the temp you want it to be. Then I could calculate how many btu are entering, and how many of them you want removing.

Around here, 8000w of LED with a decent 200mm extract, needs no aircon. To use both aircon and extraction, suggests it's either hot weather, or poor extract.

iirc a site called engineeringtoolbox.com will do all the calcs you need

 

[Travis Kelcee]

Your 12000btu unit consumes up to 1400w from the wall, shifting 3500w outside. It also works as a heat pump, reversing this, but is not quite so efficient. Or just maybe it's not a heat pump, and is just a heater. Using the defrost function.

No it's not consuming 3500 w

It's only rated for 1600 watts of input

Connected to a 15 amp double pole breaker

 

[Travis Kelcee]

In the middle of the night when it's 20 degrees outside according to my electric bill hourly usage breakdown it's consuming 200 - 400 watts of power

 

[Dankdad64]

I would need the actual measured volume of air coming though, in something like m3/h. Along with the temp it is, and the temp you want it to be. Then I could calculate how many btu are entering, and how many of them you want removing.

Around here, 8000w of LED with a decent 200mm extract, needs no aircon. To use both aircon and extraction, suggests it's either hot weather, or poor extract.

iirc a site called engineeringtoolbox.com will do all the calcs you need

Hot weather

 

[Ca++]

We have used 12000 btu in the inlet plenum, when a room with strong 200mm extract was getting too hot. This was days when outside was nearing 30c, and the cooling was worth about 3c.

Not very scientific, but perhaps offers some expectation.
Obviously an 8000w room with 2000w removed, is still a 6000w room. You you could pull 2000w of lighting today, to see what that difference would feel like. A real world test.

 

[Rgd]

tell me 9000 was to big for that small of a area.

lt should do fine..

 

[Travis Kelcee]

The wattage talk seems to have confused the issue.

You don't size HVAC equipment by wattage. You use a square footage calculation and temps. The 9K specs I posted above say the unit will work up to 300 square feet with a temp range between -20F - 129F



If your plants are not suffering currently without AC adding a 9k mini split is more than enough. It may be a bit oversized but that just means it will run less and last longer.

 

[Ca++]

The wattage talk seems to have confused the issue.

You don't size HVAC equipment by wattage. You use a square footage calculation and temps. The 9K specs I posted above say the unit will work up to 300 square feet with a temp range between -20F - 129F



If your plants are not suffering currently without AC adding a 9k mini split is more than enough. It may be a bit oversized but that just means it will run less and last longer.

No, I didn't pull you up when you misinterpreted my last post, but this isn't applicable.
The aircon sizing based on area, makes a number of presumptions. Most around the structures heat gain. Things like number and size of windows. Outside walls, North or south, roof, floor. The air exchange likely. Number of occupants and there tasks. All is presumed when people don't care to do it properly.
In this space, there is a large heat source, and also extraction. Factors of greater importance than the usual presumed one's. If this grow was pushed in a room half the size, the requirement would barely change. You still must cool the same amount of air going in. Enough to account for the heat gain of the grow. It's 8000w of gain, or 27500btu to remove. Then you could start looking at the room size needing 9000 because of building gain. Which is nonsense, because it's not a sealed room.
This needs looking at from a commercial ahu plant prospective. Where a building needs a volume of air blowing in, at a certain temperature. This ahu is the garage. Though the plant is likely portable and pointing at the rooms intake duct, it's the same principle.

The 6252a amemometer is $20 and a typical wind speed measurement device. You can put it in a duct, and tell it the duct size. Allowing it to see the air speed, and calc duct flow. Most of us guess airflow, and tend to think the sticker on the fan is achieved. Which is far from the truth. This would be a reasonable way to find cooling requirements for the volume of air passing through. The size of the floor isn't a big concideration, as building gain isn't a big part of the problem.