Water Chilling Q & A

[aSilvrHaze]

DIY Window AC chiller pics(credit goes to Budlydoright from another forum)
First 2 pics are slightly modded window unit, just bend evap coil to a lower point and set in your reservoir. Next set shows coaxial heat exchanger installed in place of evap coil, pump water in/out of the coil instead of submerging in reservoir. Last pics show a way to duct the heat from an indoor chiller to another location.

I'll be setting up a manifold to run through the new house I'm about to set up, so I'll take some pictures of that project when it comes.

 

[ttystikk]

Instead of trying to duct my chiller's heat anywhere, I just haul it inside for the winter. It heats my whole home with the 'waste' heat from my op.

 

[ttystikk]

If you set as said not much difference adding a dual stage. Just loop thru both and back to Rez. The first one is stage one. The second compressor kicks in when needed if set a few degrees above stage 1.
I had to because of stock didn't have but 2 degrees swing. On n off every few minutes for only a few. Lots of startup amps add up! Now 6 degree swing and start up down to 3 to 5 times a hour for 4 to 7 min run time.

After giving it some thought- and discovering a bit of a gift from the shop!- I would prefer to run one Ranco or one controller and have both chillers run on the same cycle.

Another bonus is that if each chiller is on a different side of the house yet runs at the same time, no one need catch on that there are two- the noise of the one covers the other!

 

[seebobsled]

After giving it some thought- and discovering a bit of a gift from the shop!- I would prefer to run one Ranco or one controller and have both chillers run on the same cycle.

Another bonus is that if each chiller is on a different side of the house yet runs at the same time, no one need catch on that there are two- the noise of the one covers the other!

With your experience of blowing 30amp breakers... really! Staggered starts will help balance start ups! Watch your amps.
Be safe.
Chillers are not illegal. Lol.

 

[Toker Ace]

OK Ty, I've been obsessing on this thread for a few days and I think the addition of a cooling tower could save you a bunch of power. The way you have your system set up, you could add the benefit of evaporative cooling while keeping your system topped off with your city water. I am trying to wrap my mind around a hybrid system of evaporative cooled air and water cooled air after rh is reached and for cooling one or two lights, 1200W max. My room is unusable save for CFLs lately because I'm too cheap to run A/C that I don"t have. I'm going to get off my ass this weekend and start getting some cheap environmental upgrades. This is a great thread.

 

[ttystikk]

OK Ty, I've been obsessing on this thread for a few days and I think the addition of a cooling tower could save you a bunch of power. The way you have your system set up, you could add the benefit of evaporative cooling while keeping your system topped off with your city water. I am trying to wrap my mind around a hybrid system of evaporative cooled air and water cooled air after rh is reached and for cooling one or two lights, 1200W max. My room is unusable save for CFLs lately because I'm too cheap to run A/C that I don"t have. I'm going to get off my ass this weekend and start getting some cheap environmental upgrades. This is a great thread.

Did you get anything going yet? I'm still struggling with the powers that be to get my second chiller back, hoping things happen soon.

Here's how your evap tower could work; get a big water tank, like a 7' diameter stock tank and build your tower above it! Now, fill the tank with fish... the water from the tank could go through a biofilter and on to water and feed plants, while simultaneously oxygenating and temperature controlling it. At this point you could install a water to water heat exchanger in the fish tank from the HOT side of a water cooled chiller (that is, the part carrying heat away from the chiller) and use the cooling tower to shed the excess heat! This would work great during the summer and it would be all the cooling one might want all winter, lol

 

[aSilvrHaze]

Is there any way to determine the cooling BTU capacity of heat exchangers, like the ice box? Somewhere I remember reading a figure around 6,000BTUs, but I'm not sure for which size that was. I recently found a couple of water-to-air heat exchangers on ebay, 12" link & 8" link. They're used to heat air using hot water and are rated at 26k BTUs for the 8" and 50k BTUs for the 12". I'm assuming these numbers would change quite a bit going from heating to cooling, but I really don't know....

 

[seebobsled]

Is there any way to determine the cooling BTU capacity of heat exchangers, like the ice box? Somewhere I remember reading a figure around 6,000BTUs, but I'm not sure for which size that was. I recently found a couple of water-to-air heat exchangers on ebay, 12" link & 8" link. They're used to heat air using hot water and are rated at 26k BTUs for the 8" and 50k BTUs for the 12". I'm assuming these numbers would change quite a bit going from heating to cooling, but I really don't know....

Yes 6000 btu for 6" , 8000btu for 8". That is if they are getting the 3-5 gallons per minute! Lower the flow drop BTUs.

 

[seebobsled]

Also I think those heat ex changers are thick for the btu rating. Check for air flow rate. They don't need air flow as much for heat gain if convection is available. Like a wort chiller, it works more on convection.

 

[ttystikk]

I have a bunch of the 8" models, and while they are thick, they do require some pressure from a good quality online fan to work properly. The other necessary ingredient is that the water temp in the heat exchanger be at least ten degrees cooler than the target temp of the room, and a bigger temp difference is better.

It's become clear to me that I need some heater core/exchanger units that are much larger in cross section than these little 8" duct sized items. I'm thinking about using a radiator from a small car and a squirrel cage blower to yield the cooling peer needed for bare bulb gardening.

Just a tease; I have a trick up my sleeve for my upcoming vertical bare bulb setup. I'm not spilling any beans yet, but you'll know it when you see it...

 

[seebobsled]

Hydro innovations are 1" thick his link is 3" thick. I got the 8" ice box exchangers without the plastic shroud from H.I. off ebay. I made a double exchanger now 2" thick and it works well. Take 2 ice boxes with water and air ran inline. Should help you for now.

 

[stickyfing3rs]

hey tty, just got a quick question for ya. I'm sure it's been posted but i can't find it. I'm wanting to run 2-4 systems off of one chiller (not big systems). could you point me in the right direction for the solenoid valves and temp controller i would need to run the cool coils? and also, I'm sure I'm going to have to upgrade but i have a 1/4 hp chiller. how many gallons do you think i could effectively cool with the cool coils and that chiller? everything is over insulated and in a sealed room so the chiller shouldn't need to try and keep up with that. thanks a bunch

 

[ttystikk]

Also I think those heat ex changers are thick for the btu rating. Check for air flow rate. They don't need air flow as much for heat gain if convection is available. Like a wort chiller, it works more on convection.

They need to be thick to efficiently exchange heat with air. Air has very little thermal mass, so it needs all the surface area it can get for effective heat exchange. By comparison, a simple copper line in the RDWC effectively exchanges heat in a water to water situation.

 

[ttystikk]

Hydro innovations are 1" thick his link is 3" thick. I got the 8" ice box exchangers without the plastic shroud from H.I. off ebay. I made a double exchanger now 2" thick and it works well. Take 2 ice boxes with water and air ran inline. Should help you for now.

Too expensive and still not enough heat exchange. I need a proper air handling unit, on the cheap. The lines should be sized for water, so that's why I'm thinking a furnace style squirrel cage fan blowing through an old car radiator might be effective.

Woodsmaneh has something like this. I should ask.

 

[seebobsled]

ttystikk, look through the trees.
stickyfing3rs asked a question

 

[ttystikk]

hey tty, just got a quick question for ya. I'm sure it's been posted but i can't find it. I'm wanting to run 2-4 systems off of one chiller (not big systems). could you point me in the right direction for the solenoid valves and temp controller i would need to run the cool coils? and also, I'm sure I'm going to have to upgrade but i have a 1/4 hp chiller. how many gallons do you think i could effectively cool with the cool coils and that chiller? everything is over insulated and in a sealed room so the chiller shouldn't need to try and keep up with that. thanks a bunch

The secret is to run the chiller at the target temp you want your RDWC systems at, or a couple degrees below. This way, no temperature control is needed! This for me is right about 60 F, so set the chiller for 55, and the RDWC runs at 63 or so.

 

[stickyfing3rs]

thanks man i was thinking to deep into it, like solenoid valves to regulate water flow to each system. u made my life easy

The secret is to run the chiller at the target temp you want your RDWC systems at, or a couple degrees below. This way, no temperature control is needed! This for me is right about 60 F, so set the chiller for 55, and the RDWC runs at 63 or so.

 

[ttystikk]

thanks man i was thinking to deep into it, like solenoid valves to regulate water flow to each system. u made my life easy

Damn right I did! You're welcome!

 

[CelticEBE]

Damn right I did! You're welcome!

ttystikk

Do you run straight water in your water cooled system, or a 50% propylene glycol 50% water mix?

Does anyone know of a cheap source for propylene glycol?

 

[ttystikk]

ttystikk

Do you run straight water in your water cooled system, or a 50% propylene glycol 50% water mix?

Does anyone know of a cheap source for propylene glycol?

Since my system is entirely indoors, I can and do run straight water. If part of your system is outdoors in a climate that might freeze, you will need to get glycol. I don't know where to get it in bulk. Propylene glycol is the non toxic version of antifreeze, that's why you use it instead of ethylene glycol. I'm told that glycol in the system aids efficiency slightly and lubricates the pump. I don't have proof of these assertions but they make intuitive sense to me.