HVAC experience? / AC questions

kingromano

Well-Known Member
edit: ah it's electric ignition
i hate these gadgets
i have one i paid 350euros collecting dust right now

nothing beat a pilot if you want my opinion .. way more secure and reliable, and clean burnin
 
Last edited:

2com

Well-Known Member
I'll say this though, to whoever, especially because of the claims I hear others making, I was surprised that a 10x10x8 with 2000W of LED (max), other standard equipment (including dehu, which is quite a bit of heat), and say 5500 btu of burner warranted a suggestion of a 24kbtu ac - with the note that 18kbtu might be just shy of enough.
I don't have any experience with a "sealed" room. The room was recirculating before. So it may be surprise do to not having experience in such a setup, and the cooling/dehu requirements in a "sealed" room.

I hear people say (can't confirm, unfortunately) pretty regularly that they run a similar sized room (pretty standard) with 2000-4000W of HID (I honestly can't remember how many say they're sealed or not, but some of them) and don't even use 24kbtu of cooling. Hearsay, different climate, different setup. But still. Their starting/ambient temps (and climate) can't be much colder than ours to start with.

It's canada. It's winter for 8 months, it's cold (and dry, in the winter), haha. with about 1700W in there, they had to add a heater during lights on, and it still could've been hotter, when setup as recirculating room.
also 2 tons of AC may be overkill. How much wattage are you running in that 10x10?
Yea, I wonder that too.
 

kingromano

Well-Known Member
with 2kw of lamps in cold climate 3.5kw(1 ton) is way enough
2.5kw would probably work too .. providing a better dehumidification than the 3.5kw too

you want 25celsius minimum inside ..with led more 28 degree because they develop less heat at the canopy than hps (no infrared)

what you will need for sure is a big ass dehumidifier
the ac will run sometimes .. beware of short cycles with oversized AC.. you dont want it to start/stop more than 6 times per hour ..

the advantage of minisplit inverter is that the computer of the AC adjust the speed of compressor depending of the cooling/heating needs.
windows AC are "all or nothing" tech .. meaning they will turn on at full power .. cool the room and stop when the temp reach the set temperature

so .. do not oversize
 

Onextremebuzz

Well-Known Member
I'm providing what's needed to answer the question. Here is the original question(s) I posted:

Question one: Do these 240V acs need 3 wire, or 4 wire (do they need a neutral)? Answer: 3 wire; No neutral.
Question two: What sort of amp draw for a 24000 btu, inverter, split ac? Answer: Varying.

I appreciate you're trying to help. But what question are you even trying to answer? You're just bringing up a bunch of details that you don't need to know about. "Might have to use a lower awg if it's more than a certain distance." Yea, I know this... "Please update us with everything about your grow..."? ...What? Haha.

Things are "left out" on purpose because they're irrelevant to the original question, so as to try and avoid this. This isn't a "help me design and spec a grow room thread". That's been done already, though I don't feel totally confident with what I got from doing that. I know you're trying to help.
I'm trying to answer question one. Lol. But I'm just trying to give other ideas in case something has been missed.
 

2com

Well-Known Member
I'm trying to answer question one. Lol. But I'm just trying to give other ideas in case something has been missed.
Oh ok, hah. Yea, I think I've got that sorted. And it's not any extreme distance run or anything requiring "de-rating" etc.
 

Onextremebuzz

Well-Known Member
20 amp 4 wire 12/4 one to neutral one to ground and 2 hots. Its appears OP only has residential power so it's not going to be more complicated than that. Make sure you do it proper and have a conduit. A lot of power running through that line. Make sure your connections are tight as hell too
 

2com

Well-Known Member
Replies in body, below:
with 2kw of lamps in cold climate 3.5kw(1 ton) is way enough
2.5kw would probably work too .. providing a better dehumidification than the 3.5kw too

Hmm, ok. It's gonna tricky, it sounds like. Because the requirements in the summer vs winter differ so much.

you want 25celsius minimum inside ..with led more 28 degree because they develop less heat at the canopy than hps (no infrared)

Yup. Fully aware of this often unheeded advice, it's hard to fully understand or do at first. I know to keep the temps up where they need to be to get the plant up to 82*F ish. From experience :)

what you will need for sure is a big ass dehumidifier
the ac will run sometimes .. beware of short cycles with oversized AC.. you dont want it to start/stop more than 6 times per hour ..

I'm wondering if I'm too concerned with the AC, and not enough with the dehu., too. Haha. Especially with no HIDs effectively drying out the environment some.

the advantage of minisplit inverter is that the computer of the AC adjust the speed of compressor depending of the cooling/heating needs.

Yea, this is exactly why I want/need an inverter style ac.

windows AC are "all or nothing" tech .. meaning they will turn on at full power .. cool the room and stop when the temp reach the set temperature

There are some, at least one, model of window ac with inverter tech - the Midea U window ac. Hard to find in canada, and I don't know of the quality and everything.

so .. do not oversize
Thanks for the tips.
 

getogrow

Well-Known Member
20 amp 4 wire 12/4 one to neutral one to ground and 2 hots. Its appears OP only has residential power so it's not going to be more complicated than that. Make sure you do it proper and have a conduit. A lot of power running through that line. Make sure your connections are tight as hell too
12/4 ?
Dude read the thread.... he has this covered. i think he knows more about electricity then you do ....no big deal though, thanks for trying!
 

Onextremebuzz

Well-Known Member
12/4 ?
Dude read the thread.... he has this covered. i think he knows more about electricity then you do ....no big deal though, thanks for trying!
When the going gets tough I guess you call the guys that know what they are doing. I know some about electricity. I'm not licensed though. Just enough to do what I need to do. I didn't fully read the thread I kinda got lost in all the technical stuff. But that part stood out. So I threw my .02 in.
 

getogrow

Well-Known Member
When the going gets tough I guess you call the guys that know what they are doing. I know some about electricity. I'm not licensed though. Just enough to do what I need to do. I didn't fully read the thread I kinda got lost in all the technical stuff. But that part stood out. So I threw my .02 in.
Well thank you for your time sir! you tried!
 

MidnightSun72

Well-Known Member
Hi,

I don't know exactly what make/model of AC I'll be picking up, so I'm wondering if I should just run 3 wire + ground, or 2 wire + ground? Some of these units use a neutral, right? Maybe it'd be best to run the 3 wire + ground, just in case, so it's there.

I'm thinking of/looking for 24000 BTU at most, 240V, Inverter (mini split or window/through wall design) and would also like to know, what sort of amperage these units *actually draw* - as I'm getting some mixed info that isn't adding up or making sense to me.
24K should draw around 10a depending on efficiency??? My 30K is 12.5amp draw. But I dozed everything for the max fuse recommended which is 20a.

you ever think about a 24K window AC a lot cheaper to get into. I usually get my ACs from a local auction/scratch and dent. $150-$200 for 12-24K air conditioners. And the 230V ones never sell sometimes they go even cheaper cuz everyone buys 110V
 

2com

Well-Known Member
24K should draw around 10a depending on efficiency??? My 30K is 12.5amp draw. But I dozed everything for the max fuse recommended which is 20a.

you ever think about a 24K window AC a lot cheaper to get into. I usually get my ACs from a local auction/scratch and dent. $150-$200 for 12-24K air conditioners. And the 230V ones never sell sometimes they go even cheaper cuz everyone buys 110V
PM'd you.
 

getogrow

Well-Known Member
Just got a 24k mini split. im running 12/2 for power. I have a 20 amp breaker on it. The unit says "max fuse 30a" but its never going to get clkose to 30 amps so i decided to go witrh a 20a breaker. No pops yet. over 90f here. Im in a 12x12 with 4 lights running. Well 2k of hps and 1400w of led. Its humid so the heat kicks on the dehumy too. Its almost too big. I dont think its "short cycling" but iom not 100%. It runs 3 or 4 times an hour.

Look at the rating. Most are normal but some are different and need more or less power. Look at the max fuse rating and the actual amp draw.
 

2com

Well-Known Member
Just got a 24k mini split. im running 12/2 for power. I have a 20 amp breaker on it. The unit says "max fuse 30a" but its never going to get clkose to 30 amps so i decided to go witrh a 20a breaker. No pops yet. over 90f here. Im in a 12x12 with 4 lights running. Well 2k of hps and 1400w of led. Its humid so the heat kicks on the dehumy too. Its almost too big. I dont think its "short cycling" but iom not 100%. It runs 3 or 4 times an hour.

Look at the rating. Most are normal but some are different and need more or less power. Look at the max fuse rating and the actual amp draw.
Hey bud.

Thanks for sharing your new gear setup. Nice one on getting a mini split. Did you have it installed?

Man, I don't see how I could need a 24k btu then, in a 10 x 10 with 2000-2200 watts of led.
Is this a "sealed" room? I assume it is. If so, tanked co2 or burner? I can't remember if you told me before. How man btu is the burner if there is one, and how much wattage/amperage is your dehu?

I think any decent, inverter (variable compressor) split ac is gonna do it's best to run at varying, and limited speeds, etc., if "oversized" (within reason). They can just slow down, instead of short cycling on and off.

Thanks for the tips too.
 

getogrow

Well-Known Member
Hey bud.

Thanks for sharing your new gear setup. Nice one on getting a mini split. Did you have it installed?

Man, I don't see how I could need a 24k btu then, in a 10 x 10 with 2000-2200 watts of led.
Is this a "sealed" room? I assume it is. If so, tanked co2 or burner? I can't remember if you told me before. How man btu is the burner if there is one, and how much wattage/amperage is your dehu?

I think any decent, inverter (variable compressor) split ac is gonna do it's best to run at varying, and limited speeds, etc., if "oversized" (within reason). They can just slow down, instead of short cycling on and off.

Thanks for the tips too.
I found out that i do not "need" 24k but i didnt know that until after i bought it. Im borderline short cycling. it was 100 bucks more then the 12k unit so i had to , correct ?
heat= 2x hps 1k , 1400w of led and a 35-40 pint dehumy. (not sure on power consumption of the dehumy... im guessing around 3-6 amps. 3-800watts give or take a hundred.) Not sealed. no co2. Oh...an the hps are in cooled hoods.

If i had 4x 1k hps with no hoods then that would be a perfect unit for the setup. The way it is , im sure i could seal it and add gas if i wanted to. That was the original goal.

All in all , i have done a lot of hvac research to come up with this conclusion but im not confident in my words. Oversizing is wrong. Im sure my power bill will let me know about it too!
My buddy grabbed a 12k unit and its not quite enough so i would rather be in my shoes then in his! In his defense , his room is sealed and has a burner in it. He uses led but LOTS of them.
 

2com

Well-Known Member
I found out that i do not "need" 24k but i didnt know that until after i bought it. Im borderline short cycling. it was 100 bucks more then the 12k unit so i had to , correct ?

Correct. "This is the way."

heat= 2x hps 1k , 1400w of led and a 35-40 pint dehumy. (not sure on power consumption of the dehumy... im guessing around 3-6 amps. 3-800watts give or take a hundred.) Not sealed. no co2. Oh...an the hps are in cooled hoods.

Oh, not sealed and no burner. I maybe shouldn't directly compare then. What's the "lung room" environment like? Or is the supply air from outside and going right back outside?

If i had 4x 1k hps with no hoods then that would be a perfect unit for the setup. The way it is , im sure i could seal it and add gas if i wanted to. That was the original goal.

All in all , i have done a lot of hvac research to come up with this conclusion but im not confident in my words. Oversizing is wrong. Im sure my power bill will let me know about it too!
My buddy grabbed a 12k unit and its not quite enough so i would rather be in my shoes then in his! In his defense , his room is sealed and has a burner in it. He uses led but LOTS of them.

I'd rather be in your shoes there too.
Replies in quote^.
 
Top