Water Chilling Q & A

[ttystikk]

Cool... let's muddle through this bro. Maybe it will help others.

Can you at least install it? What happens, what doesn't?

It downloads but then the phone can't find it

 

[ftwendy]

It seems there's no way to draw with Sketchup on tablets -- you can only display drawings. There are lots of people complaining about this so hopefully google does something about it sooner than later. Do you have a laptop or desktop?

 

[KitsapGrapeApe]

You'll need to separate your water droplets from your outgoing air, but yes. It really IS that simple. If your cooling system water is 60f, your humidity at 80f air temp will be about 70%. Perfect. Colder water will reduce dewpoint, and therefore RH.

Yes, it really is that simple. Simple and EFFICIENT. How efficient? My 2 Ton chiller keeps up with 16kW of bloom lights, AND dehueys as per the example above, AND cools all my RDWC. I know a lot of hvac professionals- on this site- who will sell you four times that much capacity in AC for the same job- and it won't work as well.

Are you rubbing air cooled lights? I'm trying to figure out how to seek some rooms up with my limited power. I'm trying to run 2 12k rooms on different light cycles, all the bells and whistles, fans, pumps yada yada yada and only have 140 amps to play with. Do you know off hand what kind of amperage draw say a 5 ton unit would draw ?

 

[Swany]

Are you rubbing air cooled lights? I'm trying to figure out how to seek some rooms up with my limited power. I'm trying to run 2 12k rooms on different light cycles, all the bells and whistles, fans, pumps yada yada yada and only have 140 amps to play with. Do you know off hand what kind of amperage draw say a 5 ton unit would draw ?

Between lights @ 60 amps and a 5 ton unit at around 35 amps you'll have plenty of power left for the rest of your equipment. With good electric ballasts you can get that power usage down below 50 amps for the lights. I believe Tty will confirm you can run less than 5 tones of chilling if you're using vented hoods. And if you're in Kitsap County WA and need an electrician I would love to wire your room ;-}

 

[ttystikk]

It seems there's no way to draw with Sketchup on tablets -- you can only display drawings. There are lots of people complaining about this so hopefully google does something about it sooner than later. Do you have a laptop or desktop?

Galaxy Note 2 phone.

 

[ttystikk]

Are you rubbing air cooled lights? I'm trying to figure out how to seek some rooms up with my limited power. I'm trying to run 2 12k rooms on different light cycles, all the bells and whistles, fans, pumps yada yada yada and only have 140 amps to play with. Do you know off hand what kind of amperage draw say a 5 ton unit would draw ?

Yes, I'm running air cooled lights, although perhaps not for much longer. I'm going to summarize here how I get 2 tons of chilling to go so far:

Split your op in half and flip; run half of your bloom at a time and then your cooling plant only has to be half as big.

Sealed and vented hoods shed 1/3 or more of the heat from your lights. PULL air through those cooling ducts, don't push.

Having a chiller cooling circuit with a big reservoir helps it handle short term heat spikes.

Use manifolds and be able to isolate circuits by having valves at both ends; these allow for consistent temps at all points of use, and the valves let you service or alter many aspects of your setup without the need to shut down the whole system.

There is more to cool than the air; keeping water temps and humidity under control is just as important. Insanely, people insist on counting the watts used for these cooling functions separately from the rest of their environmental control costs- or worse, not at all.

If the water in the cooling circuit is 60 degrees, this sets the dewpoint in the room at that value. At 60f, that means 100% rh! But at 80f, it means 70%rh, or just about perfect. Set your reservoir temp accordingly.

I mounted my in room cooling systems vertically. They now take up the same floor space as a 5 gallon bucket. The muffin fan sits on top, blowing air down through an Icebox heat exchanger and down rigid ducting and into a 5 gallon bucket. The bucket captures the water- distilled, reuse it!- and the air blows up and out. Cooling AND dehuey, simultaneously.

Additional circuits run to 3/8" copper hvac tubing coiled in the bottom of the RDWC head bucket. This of course cools the water. This is the other reason to keep your chiller reservoir at 60f, so it maintains the temps in your buckets at the target values.

In high summer like right now, I use a few more tricks; shade the portion of your compressor that's in the sun; this improves efficiency much more than the mfrs would like to admit!

Foliar spray in your room if it starts getting too hot; the evaporative effect cools quickly and the additional humidity will help your plants withstand the heat.

Do not buy or use dedicated flip boxes, as they limit your timing options and don't save much money over just buying ballasts and timers. Now, you can have your girls in early bloom getting 12/12, and the later bloom room (you ARE running perpetual, right?! This is another huge money saver!) would get 10.5 hours of light. This means there is an hour and a half with no lights on at all, so use it wisely! Time your morning flip to happen within 15 minutes. Then, try to have as much of that dark period occur in the afternoon flip as possible. Why? Because it's hottest out in the afternoon; giving your chiller a break is like a siesta; it gives your chiller a chance to fully catch up with its heat load in case it got behind during the hot party of the day.

The RDWC systems also act like a reservoir for thermal mass purposes, since they are thermally connected at all times with the chiller circuit. This means water temps will change more slowly and that is generally good for your ladies.

 

[ftwendy]

Nice summary Tty. Lots to digest there -- thank you!

If you want an old (but working) laptop for free pm me and we will figure a way to get it to you.

 

[Swany]

I'm going to summarize here how I get 2 tons of chilling to go so far:

Great Tty - that explanation clears up a few lingering questions I had on your set up. What I want to figure out now is how to automate and time valve switching for each cooling loop. Do you do this?

 

[ttystikk]

Great Tty - that explanation clears up a few lingering questions I had on your set up. What I want to figure out now is how to automate and time valve switching for each cooling loop. Do you do this?

Hee hee hee... no, I don't. That just made things a whole lot simpler, didn't it? Every circuit sees water from the reservoir at the same temperature as every other circuit all the time. The target temp. is right about 60 f both for the optimal RDWC temp, and for optimal dewpoint.

This is a totally different approach to climate control. Now, you're just fully utilizing all the side effects of the cooling system, including the dehumidifying function.

 

[ttystikk]

The Iceboxes get a steady supply of chilling water constantly. The muffin fans blowing through them are controlled by the environmental controller, which is how it controls temps in the room.

 

[rick ratlin]

Great stuff, any advice on how to diy a cool coil? I noticed you use 3/8" copper tubing for chilling the rwdc. Is this a special copper tube, or any different from the coiled copper tubing you can buy at casa depot? Would copper be favored over stainless? Also, where'd you get that manifold?

 

[seebobsled]

304 stainless steel is best.

Copper is known to be leached into solution with salts. Some put copper sulfate on pots to stop roots from circling. I also heard people put copper in the bulkhead at the bucket to prevent plugging of tubing.

 

[Swany]

Hee hee hee... no, I don't. That just made things a whole lot simpler, didn't it?

So True ;-} I guess keeping the solution a constant 60 is not unlike the ground which is usually a pretty constant temperature. Controlling the air would be a lot simpler.

I also heard people put copper in the bulkhead at the bucket to prevent plugging of tubing.

That sounds like a good idea Bobsled. I have the plastic cone things that are made for the bulkheads I used, but the roots are probably just bunching around them. Some copper screening would keep the roots at bay, if it didn't cause a problem in the water. There are copper test kits out there. We put a device in our koi pond that has two copper bars - run a current between them and all the algie in the pond dies. The device came with a copper test kit similar to spa water test kits. If my screens are getting clogged when I take the plants down I'm going to try this.

 

[ttystikk]

Great stuff, any advice on how to diy a cool coil? I noticed you use 3/8" copper tubing for chilling the rwdc. Is this a special copper tube, or any different from the coiled copper tubing you can buy at casa depot? Would copper be favored over stainless? Also, where'd you get that manifold?

I got both the copper tubing and the 6 way Pex manifold at Home DePot. Just bend the coil around something that will make it fit into your RDWC.

 

[KitsapGrapeApe]

Thanks forthe info, I'm gonna do more research, 35 amps is workable, I have gas so I could just use gas for heaters for lights out.

 

[ttystikk]

Ok I just have kinda skimed through this. I don't know much about chilling. I bought a smaller chiller years ago, and treid useing it, but learned real fast that you gotta go big or go home with chillers.

So my question now is, are you guys talking about useing ground water to chill the lights. Like hooking your lights up to a well?

If so what do you do with the excess water, after it's pumped through the lights and is warm.

I probably have a million question. But Ill go one at a time.

You can use groundwater but I wouldn't recommend it; you'll gum up your system with mineral buildup. Instead, use a separate circuit of water for your cooling system. If you want to chill this water with an outside sources, use a heat exchanger.

I wouldn't bother trying to cool the lights themselves when you can just pull that excess heat out of the grow room. Only cool what you need to keep the room temps under control.

 

[ttystikk]

Thanks forthe info, I'm gonna do more research, 35 amps is workable, I have gas so I could just use gas for heaters for lights out.

Or, think about circulating air between rooms with lights on and those in their dark cycle. The dark room will help cool the air and will contribute co2. The warm air from the lit room will lower rh in the dark room...

 

[ttystikk]

BIG NEWS: I was getting my chiller serviced and it blew the relay. I have NO COOLING AT ALL right now, and yet I'm not overheating. WTF?

I am running city water through my water chilling system. At 64 degrees it is doing fine until my hvac guy gets back. After the 4th.

How does that work with AC? Oh, right- it doesn't.

TO REPEAT: I'm running 8kW of bloom in sealed rooms with no operational cooling system AT ALL. On July 4th. Temp is 93 today.

I'm using a lot of cold water, but I CAN. Think about it.

 

[ttystikk]

Update; thanks to a valve, I am able to run the cooling water at a low enough rate that efficiency is maximized.

Using MUCH less water now- and keep in mind that this is handling all cooling including air temps, humidity control and even rdwc.

I'm running all 8kW just to see how it does. 4kW was a walk in the park.

 

[ftwendy]

That's freaking cool..... city line in, sewer out? Is the meter in your house, or accessible? Might be worth noting how much water you use. Data........

Happy the band aid works for you bro. That's a testament.