3 ton ac cant keep up with 7200 watts.

steveydvee

Well-Known Member
Have 9 800 out the wall LED fixtures and my 3 ton minisplit can't keep up. Normal? Outside temperatures are currently 85 highs 40 lows. Have 4 hydrofarm fans on each wall in a 12x12 + 4x4 closet space.
 

Roy O'Bannon

Well-Known Member
You mean 7200watts worth of lights. correct? Plus all the other heat sources?
Is the unit charged, I have to add to mine once in a while. r410a, if I remember, you want a 5-8f degree diff on the high and low press lines with the a/c running all out. Also check the filter and drip tray/drain. Might even have to clean the blower and coils if it's dirty. There are some youtube vids that can show you how.
Here is a calculator for hvac sizing.
 
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Lordhooha

Well-Known Member
Have 9 800 out the wall LED fixtures and my 3 ton minisplit can't keep up. Normal? Outside temperatures are currently 85 highs 40 lows. Have 4 hydrofarm fans on each wall in a 12x12 + 4x4 closet space.
Lights alone call for 2.5 tons of cooling that's not figuring everything else running in the room. And counting in ambient temps outside and overall insulation and leaks.
 

steveydvee

Well-Known Member
Ended up figuring out the issue. I cleaned the filter, cut overgrown growth nearby condenser and all is working as it’s supposed to. I had 8000 watts of verticals With magnetic ballasts and it was keeping up so I was baffled. Thanks for the input anyways.
 

Lordhooha

Well-Known Member
Lol? Do the math and it’s like 25k btu requires for the job. Ofcourse if you live in an area where temperature is 100 degrees regularly then you MIGHT be right. But not in my case.
I did do the math for just the lights. You need to figure in other equipment loss due to the room itself. And outside temp. It all plays a factor. 2.5k btu is the bare minimum for your lights only. If it runs to long or not enough it's bad on equipment.
 

Freshbakd

Well-Known Member
add a dehu heat to the mix on top of those lights cant forget that beast. if you've got that much a dehu has a lot to work to do.
 

bluntblowin

Active Member
Youre undersized. Every 3 1000w needs about a ton of cooling and thats before considering the space requirements, insulation, etc. You can add a dehumidifier, that may help a bit with sensible load capabilities of the AC by putting latent load on the dehum. If you have a leak, you'll lose capacity as well.
 

Lordhooha

Well-Known Member
Youre undersized. Every 3 1000w needs about a ton of cooling and thats before considering the space requirements, insulation, etc. You can add a dehumidifier, that may help a bit with sensible load capabilities of the AC by putting latent load on the dehum. If you have a leak, you'll lose capacity as well.
3 1000 watt lights will only need 3420 btu of cooling. Not even a ton yet. Do you know how to properly figure btu requirements? Total wattage x 3.42= btu
 

bluntblowin

Active Member
3 1000 watt lights will only need 3420 btu of cooling. Not even a ton yet. Do you know how to properly figure btu requirements? Total wattage x 3.42= btu
3000 x 3.42=10,260 btu, looks like you forgot to multiply by 3 for this part.

Now let's adjust for number op provided...
9x800=7200
7200 x 3.42=24624 btu

24000/12000=2 ton
So we're at 2 tons just for lights in this application. Not taking into consideration r value of insulation, square footage, or any of the water going into the plants which also adds to load. We also don't know if he's running sealed room or not. If not, you need to account for temp of entering air. If sealed room how is CO2 being generated? If using a burner, that also adds to load.

Don't know who pissed in your Cheerios bud, I was just trying to help
 

Lordhooha

Well-Known Member
3000 x 3.42=10,260 btu, looks like you forgot to multiply by 3 for this part.

Now let's adjust for number op provided...
9x800=7200
7200 x 3.42=24624 btu

24000/12000=2 ton
So we're at 2 tons just for lights in this application. Not taking into consideration r value of insulation, square footage, or any of the water going into the plants which also adds to load. We also don't know if he's running sealed room or not. If not, you need to account for temp of entering air. If sealed room how is CO2 being generated? If using a burner, that also adds to load.

Don't know who pissed in your Cheerios bud, I was just trying to help
Yah no my brain was moving faster I did 1000 x 3.42 lol its what happens if I don't have my Adderall I'm thinking about 15 things at once.
 
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