Any Thermodynamics/Watercooling Pros Out There?

[Bobby Smith]

Before you start, this email I sent to Hydro Innovations is long, so back out now if you don't have the time to read it..............anyways, any flaws anyone can see with my logic would be much, much appreciated - please people, talk me out of this (but do so logically given the parameters I've presented, don't just say "fuck watercooling"). And you don't need to be a "pro" to respond, I'd love anyone's opinion.

Dear sir or madame:

I've corresponded with you guys before and you're great - I currently have a Hydrogen CO2 Gen and a Cool Coil in my grow room, but I'm now trying to add some more of your gear so have a couple more questions.

Real quick, my setup:

14x10 sealed room, super insulated (R19 at least, R30 in some areas) but inside a non-insulated garage (so gets to 20F in winter and 100F in summer in the garage area)
Veg tent has 700 watts (non air-cooled)
Flowering area has 2400 watts - cooltubed on a closed circuit, so heat from the bulbs is GREATLY reduced
All ballasts are digital
96 pint dehumidifier
1/8 and 1/15 chillers (but they would be gone if this idea moves forward)
Watercooled CO2 generator (run off of tap water, drain to waste)

I think that's about it for the basics of my heat producing equipment.

This room is currently cooled by a 14K dual hose portable AC (which would become the 96 pint dehuey if this idea moves forward), but that is unable to keep the room completely sealed (portables suck), so I want to go fully watercooled for that reason and for the increased efficiency (i.e. lower electric bill).

I have a crawlspace under my house which stays <=65F in the dead of summer and around 50F for the other nine months of the year.

I was planning on putting a 150-200 gallon reservoir in there (the crawlspace), and from that running a feed and return line into an ice chest (insulated "beer cooler") located in my grow room - that would basically be my "epicenter" - somewhere in the 30 gallon size range - I understand that you guys recommend a 50 gallon reservoir with a proper sized chiller, but I'm trying to use as much of the cool ambient air as possible to cool (without using a chiller), so I need to go bigger on the reservoir.

This ice chest would feed one or two 8" Ice Boxes (purely for AC needs, not for attaching inline with the aircooled lights) and one or two cool coils (reservoirs of 25 gallons and 40 galllons, respectively).

There will (eventually) be a 1HP chiller hooked up to the reservoir for the summertime, but with the ambient temps down there that (IMO) won't be necessary until May at the earliest.

Anyways, my questions are as follows:

1) How many 8" Ice Boxes do I need for this application? Can I get away with one or do I need two?
2) What size pumps do the Ice Boxes need to operate? I've read the "head at 8' for 500GPH" stuff, but that's over my head - could you simply provide a link to a pump that would power this properly for me? I'm not the brightest bulb in the box.
3) What water temp would I need to maintain in my epicenter to perform these functions? I'm guessing around 60F (as your website recommends a 20F difference for supplemental AC).
4) At what temp is the effectiveness of the chiller seriously compromised? Whereas the crawl space is 65F in the dead of summer, I realize that the chiller will certainly heat it up to some extent (but I'd be shocked if it ever got over 85F) - and no, the chiller can not be located outside, it must be in the crawlspace for security reasons.
5) Is 30 gallons a reasonable size for my epicenter (located inside the grow room), or would I want to go bigger?

Also, every piece of equipment is going to be run off of its own pump and controller, so I'm not planning on setting up a manifold - my 1/6HP pumps suck 600 watts, so to leave that running fulltime to pressurize the piping would defeat the purpose of going watercooled to me.

Again, really appreciate everything you guys do and I'm sorry for how long this was - just wanted to get all the details in there.

Thanks,
Bob

 

[motta-tokka]

Did not read all of that but from what I have discovered is that its not worth "dealing with the extra heat". I would rather remove it entirely in summer and if needed, or use the air heat in winter. Think about it ;) I run sealed, co2, chiller, etc.

Basically adding a additional fan to control light temps, allowed me to vent that heat outside. Its on a dial now so when its really cold I actually have it all the way down or off! My garage is 51F-45F at night and the 1000 watts keeps it 77-81 no problem. THe a/c is set at 82f as a security precaution.

 

[Bobby Smith]

Did not read all of that but from what I have discovered is that its not worth "dealing with the extra heat". I would rather remove it entirely in summer and if needed, or use the air heat in winter. Think about it ;) I run sealed, co2, chiller, etc.

Basically adding a additional fan to control light temps, allowed me to vent that heat outside. Its on a dial now so when its really cold I actually have it all the way down or off! My garage is 51F-45F at night and the 1000 watts keeps it 77-81 no problem. THe a/c is set at 82f as a security precaution.

Hey man, thanks for taking a look but I think it's a little more complicated than that - I'm trying to figure out the cooling power of water when using the earth instead of a chiller (to oversimplify a bit).

Fans in/out of the garage are not possible - the portable AC's current setup is pulling in cool air from the crawlspace and exhausting into the garage - there are no possible intake/exhaust areas in the actual garage.

Anyways, I'll post the answer I get from HI in this thread.

 

[Bobby Smith]

Bumpity bump.........

 

[TrichromeFan]

The biggest problem I see with using the earth for cooling, is lack of control. You might have water temps sit at 72 degrees, and not be able to do a thing about it with the earth being the cooler. Are you trying to avoid costs on the equipment and electric? The only difference would be the cost of the chiller. You could always incorporate an underground holding tank with a chiller as well. It may work more efficiently. Perhaps...

Did I read correctly, are you sending the ac exhaust back into the grow area?

-TF

 

[Bobby Smith]

The biggest problem I see with using the earth for cooling, is lack of control. You might have water temps sit at 72 degrees, and not be able to do a thing about it with the earth being the cooler. Are you trying to avoid costs on the equipment and electric? The only difference would be the cost of the chiller. You could always incorporate an underground holding tank with a chiller as well. It may work more efficiently. Perhaps...

Did I read correctly, are you sending the ac exhaust back into the grow area?

-TF

No, definitely not trying to avoid costs on anything - take a look at my journal if you wanna see waste and excess at its finest.

That said, I am definitely cognizant of my electricity usage in a non-medical state with draconian penalties, and would like to do everything I can to reduce it.

Also hate that I had to use a portable AC (can't really have an HVAC guy into my garden where I am) which is going to exhaust smell and not work efficiently - FYI, no, not venting back into the garden - intake is from the crawlspace, and exhaust is through the insulated roof of the room and into the garage (pic attached).

"You could always incorporate an underground holding tank with a chiller as well. It may work more efficiently."

That's pretty much exactly what I'm trying to describe - the water temp would be kept at 60F (or less, guessing probably in the low to mid 50s is where it would be without the heat from my garden) via the natural cooling of the earth supplemented with a 1HP chiller when needed - so the water never gets above 60F, but the chiller/pump only run when they're needed (controlled by a Ranco controller or something like that - obviously still some details to work out).

Would still be able to control temps down to a degree (Sentinel CHHC-1) with the use of the Ice Boxes as an "AC", and this would actually allow me more control of my grow - when I want cooling I'd get it without the (sometimes negative in cases of low RH%) additional dehumidifying that AC provides (14K AC would then be my large dehuey).

 

[motta-tokka]

I would like to chime in one more time for ya.. Check out the hydro innovations site for what they tell you to use for cooling.. If you think you are going to try to get away with using less your going to have yourself problems like I did. I experimented for months with it and now dialed in without it.

Having a res in a cool remote location is a great idea (I had the same). Think of a few things.. Gravity for the pumps to travel upwards, feet of travel, heat given off by the pump running (hopefully with a timer to be on only when you need it), heat given off by the lamps and anything else where the icebox will be located, that will slowly heat the water. Volume of water and then the temp of water will be the two biggest concerns in my opinion with or without a chiller. Thermo cooling would be great if you could find a cheap DIY style, but from what I have seen they were crazy expensive, AND imagine all the feet of travel for that? If you can find away around the problems that is a awesome solution using less energy than a chiller.

Again if you have enclosed hoods then the bulk of your heat should be coming from the lamps, which you could easily solve by taking air from a cool place (outside the grow), to the lamps, right back outside or somewhere it could go where it would not matter much (a attic in winter is awesome!).

Hopefully the people who have had luck can chime in but if they do you will more than likely hear two things.. Big reservoir, big chiller.

I would post a big pic of the whole tent but I don't have a wide shot of the whole thing.. This kind of sums it up.

http://i617.invalid.com/albums/tt254/mmjspots/DSCN3875.jpg


I am sure it could work for anyone. It could have worked for me too if I would have purchased a bigger cooler and more water.. At that point I figured that those purchases, PLUS the cost of electricity to make them work, is not worth dealing with lamp heat when you could just remove the heat entirely from the space required.

Take care and happy growing. :damnhippie:

 

[RMCG]

I still think adding in a heat x-tractor would help pull down your big res temps down.


You have 2 temps to deal with entering water temp and leaving water temp, multiplied by 2.

EWT/LWT to your iceboxes and EWT/LWT going in to your big res in the crawlspace.

If you feed your iceboxes from your res, then on the return manifold, have that go in to another icebox/heat x-tractor that is pulling cool (50-65*) FROM your crawlspace and ducting that hot air outside, your EWT going back in to your res will be greatly reduced.

So lets say water leaving your Iceboxes in your room is at 90* (LWT).

Now it enters the heat x-tractor (EWT of 90*) and has 50* air blown across it, you will get a T diff of ~20* as it will equalize. So now the EWT of your big res is 70*. Much less heat that has to 'passively' dissipate in to your 50* crawlspace.

Evaporative cooling works better than passively cooled, but a wide and shallow res in your crawlspace would work better than a cylinder (tall/deep) with very little surface area for the heat to escape (think bath tub vs barrel).

 

[f1ydave]

Well I can't comment on everything you guys have mentioned.

Water-cooling is not efficient because of the cost of pumps to constantly run the water. Would you be able to remove the chillers? Maybe. You would need a reservoir designed with channels/walls built it in. You would need to figure out the time needed to cool the highest return temp so you could adjust for the flow needed.

As far as A/C goes, get rid of the portable and get a Mini-split. You can self install this drilling a few holes and mounting it. It is MUCH more efficient to run a mini-split, they say its 40% more efficient than central air. They exchange heat and not air. This allows you to have a truly closed environment.

You mentioned a freezer, I am not sure what this is supposed to accomplish. Freezers are designed exactly like refrigerators. They are designed to maintain a constant cool state, not constantly cool a warm state. Bringing hot/warm water in repeatedly will not be able to be cooled by a freezer.

You need to design an alternative way to "process cool".

 

[Bobby Smith]

Motta - thanks, appreciate the input. Right now in the room there's a 400HPS running (not aircooled at all), and the room stays at about 68-70F.

The flowering setup is 4 600s in one long cooltube (pic attached), with a 6" inline before and after the cooltube (both 425CFM) - air is being pulled from the crawlspace, through the lights, and then exhausted into the same exhaust vent as the AC (there's a "y" they share on both vents) - haven't run it yet, but I'm assuming I might have to put the fans on a temp control because I may NEED the heat from the lights (during winter) to get it up to 82F in order to maximize my CO2.

As far as things being controlled, there'd be two cool coils and the Ice Boxes to control, so there'd be three Ranco controls for the pumps for those three circuits - none of the pumps would run until the Ranco turned it on.

Same story for the chiller/pump combo - they'll be controlled by a Ranco and will sit idle until they're needed (I'm doing this for my two reservoirs immediately anyways, as the thought of a 200 watt pump running 24/7 for a chiller that never turns on irritates the shit outta me, in addition to MAKING the chiller run more because it's heating up the water :swear).

The travel distance wouldn't be much at all - no more than 6' from the reservoir in the crawlspace to where the Iceboxes would be mounted.

RMCG - THANKS FOR REMINDING ME!!! Great idea, will definitely implement that when and if I do this - already have the 6" fans running for 12 hours a day, so putting the return Ice Box right in front of that would be budda :)

Dave - not sure who mentioned a freezer, but it wasn't me. As far as the pumps constantly running, look up three sentences - that will not be the case, and is the reason I specifically told the HI dude that I'm NOT gonna run a manifold that stays pressurized (and use a constant 600 watts to do so).

Take another look if you're interested, pretty sure that this can and will work - regardless, we'll all know soon enough :)

-The Guinea Pig

 

[TrichromeFan]

Ok,
I have a question for you, that you may not have an answer for yet.
What is the humidity level that you are at in your room? Reason why I ask, is that I heard that the cool boxes are best for people in dry environments, an they can actually raise the humidity. Or so I've heard.

No question that you are a thinker, who doesn't mind experimenting.
Any thoughts of possibly just using a 2 ton window mount AC, rigged into a box, as to cool off the compressor and such? That way, you could migrate from the portable, and just use a dedicated dehuey. Just a thought. Not poo-pooing your idea, it would just occur to me to be a more simplistic approach.

-TF

 

[Bobby Smith]

Ok,
I have a question for you, that you may not have an answer for yet.
What is the humidity level that you are at in your room? Reason why I ask, is that I heard that the cool boxes are best for people in dry environments, an they can actually raise the humidity. Or so I've heard.

No question that you are a thinker, who doesn't mind experimenting.
Any thoughts of possibly just using a 2 ton window mount AC, rigged into a box, as to cool off the compressor and such? That way, you could migrate from the portable, and just use a dedicated dehuey. Just a thought. Not poo-pooing your idea, it would just occur to me to be a more simplistic approach.

-TF

Lol, I'd have to "really" run it first before I gave you an answer - have been building since July with no end in sight.

That being said, those Ice Boxes do not raise humidity (as per the Hydro Innovations website - see question #3 in this link: ), and with my AC being able to be used as a 96 pint dehuey, humidity will not be an issue in the least (if it is, also have my current 25 pint dehuey I can add into the mix).

And yeah, have definitely considered building a plenum and running cool air into the back of a window AC, but I really think that letting mother earth (I'm not a hippy and don't know why I used that term, but it seemed fitting) handle my cooling seems like the best idea.

Plus, as you can see from that PVC monstrosity, I kinda like doing my own thing and being different :afroweed: - I can't compete with you med cats on wattage, but I'm currently unemployed and have more money than most, so why the heck not try to be innovative? :icon_spin:

After all, it is a competition, right? :)

Hell, if nothing else it'll let me show you guys how bad an idea it is to watercool a grow room :thinking

I really, really appreciate all you guys' input - hopefully you guys will save me a headache or two while getting this setup.

Oh, last question - can't find any distributors of HI gear around me and won't order off of the Net - how hard would it be to find someone around me to build me a custom-sized Ice Box? Who would I even talk to about that?

Lol, I go from not being able to change a tire last year to Captain DIY............life is a crazy ride people, enjoy it while you can :heart

 

[RMCG]

Go back into my IceBox for A/C thread.



There is a spreadsheet with dimensions of car heater cores. Just make a plexiglass shroud for it, or order something from one of the PC overclocker sites.

Cost like 22$ from NAPA or wherever. Now that you can change a tire, I'm pretty sure you can whip up a plexiglass box with a 6" or 8" flanges. :*)

 

[Bobby Smith]

Go back into my IceBox for A/C thread.



There is a spreadsheet with dimensions of car heater cores. Just make a plexiglass shroud for it, or order something from one of the PC overclocker sites.

Cost like 22$ from NAPA or wherever. Now that you can change a tire, I'm pretty sure you can whip up a plexiglass box with a 6" or 8" flanges. :*)

So something like this? (or two of these?)

 

[RMCG]

So something like this? (or two of these?)

Exactly.

The PC O/C guys use Nova cores, but as long as you can make a box to fit and have room for flanges, the more surface area the better.

 

[Nobodynobody]

Look on HI and water cool garden site that works with HI. Check and read all the FAQ. it will answer a ton of things on both sites.

Man to much to say on most post here all ready. Ill talk about the ones that are not on those sites.

For keeping a chiller where it keeps cold is idea. 12/12 works find because it has 12 hrs to let the water temps drop. Now the down fall. Your veg room is going to need a better idea.

Icebox VS GlassH2Ofixtures. I say the glass all the way if your all ready this far in to it. Icebox seems to be more of a better usage for AC

Check out Best Coast Growers site also for other info on ideas on cheaper Pluming pictures. There is a ton of ideas for not using a chiller!

Few or you guys have vary low temps. Well with enough $ you can buy a compressor less water chiller that works off temps below 55F.

 

[TrichromeFan]

Sweet DIY cooler idea with the heater cores, RCMG!

 

[Bobby Smith]

Lol RMCG, you are the man :)

Definitely gonna go with those heater cores instead of Ice Boxes - twice as big for 1/4 of the price.

Have a new plan in place, but I need to give it a little more thought to make sure it works in theory.

Nobody, I've reasearched this for the past 18 months and have spent well over 100 hours reading and watching everything related to watercooling - I feel like I'm at the saturation point for my knowledge, so now it's just time to put it to use.

Also, my veg room is a 2x4 tent located inside the 14x10 sealed room, so its atmosphere mirrors that of my flowering room.

I'll keep you guys in the loop with what happens, but this idea is going to happen in some form or fashion within the next month or two.

 

[Bobby Smith]

The link below has some sick handiwork - I remember this dude's threads from a while ago, he's sick with the custom work.

Check out posts 52-61; post #58 looks to have a custom car heater core setup (pretty sick).

http://www.invalid.com/grow-journals/131873-sog-grow-room-op-2.html

 

[TrichromeFan]

Sweet DIY cooler idea with the heater cores, RCMG!

Oops! :joint:

Sorry, RMCG. Dyslexic typer here.