Ac sizing

Discussion in 'Grow Room Design/Setup' started by leagalAlaska, Jul 16, 2019.

  1. Hello, I’m getting ready to design a new room. Here’s the basic concept
    Total canopy is 500 square feet, 320 dedicated to bloom, 68 square feet dedicated mother space, and the rest is for veg.

    20,000 watt phantom de lights in flower
    The veg room is 315 watt x6
    The mothers are going under 8 bulb t5 x8

    Probably going to do a current culture 13 gallon dwc for bloom

    For veg I’ll do three 4x8 tables
    And mothers in no till soil in a separate room

    My previous grow was all under 40 315 watt CMH in bloom and two separate rooms. We were able to keep it cool with a 5 ton ac unit ducted to both rooms. ( didn’t have a dual zone ac was an issue)

    Do you think a 5 ton unit will keep up with 20 d.e lights? I think it would given the 40 lights at the last grow.

    Pic from last grow room for example.

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  2. If not im sure you have the means to upgrade. Very impressive now those are some beautiful plants. This is a real grow op my new hero. whatever you are doing keep doing just that. Just curious as to what your electric bill is.
  3. Yeah I second that what is the electrical bill.

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  4. A 5tonn ac unit roughly 54,000 btu is plenty . are you planning on ducting the ac throughout the set up? Multiple diffusers placed in thhe room? I thing that should be plenty.( overkill even) but as long as you have it ducted properly. :) looks amazing. Btw.

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  5. The electrical bill was right around 2000 a month with the lights, the ac only ran in summer, I had one that couldn’t operate through winter, but during winter 2 10 inch hyper fans would cool the room more then enough, we just added a automated louvre outside on a thermostat. Most months the bill was 1800 and the highest was 2000. And yes I plan on running a 10 inch duct across the entire bloom room in center and putting ports every four feet on both sides. Thanks for the input.

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  6. Also for reference a 40,000 watt bloom room and a 20,000 watt veg runs us 7000 a month in electric. IMG_3562.JPG

    This is the 40,000 watt bloom room I’m working with. It was built by a friend and 40,000 is about double what he needed to bloom under. Cooled with 16 hyper fans and ran at night during the summer to keep temps down.

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  7. Rule of thumb is around 4 btu's of cooling per watt of HPS light.

    20,000 watts of HPS light which many DE's are 1100 watts.

    20,000 x 4btu's per watt = 80,000 btu's needed of cooling. There is 12,000 btu's in a ton of AC. 80,000/12,000 = 6.66 tons of AC needed.

    You are in Alaska though so it's possible you could get away with 5 tons. Undersized equipment is going to be ideal for better efficiency probably 3/4 of the year when it's not super hot out. More cooling power costs more to run the rest of the year when it's not hot out but is able to keep up when you need it to.
  8. Thank you, that’s what I was kinda thinking, but I always want to double check with other people before I commit to something that big.

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