So first, a little background on this project;
I've been having a problem with my BC29 overheating after I retrofit a 150W MH into the hood. Temps in the unit shot up to 87 at one point (yikes!).
Click for full size
So I decided to do a low-tech approach and install 4 80mm fans into the hood in the "doors" of the BC29:
Door #1 in the front:
Click for full size
Door #2:
Click for full size
And it helped, quite a bit. I'm peaking out at about 81 degrees now, which is still too high for my taste.
So it's time to do something a little more drastic I think. Now chillers IMO are awfully expensive. I started looking around a things like the Ice Probe, and the mini chillers from JBJ, etc. But none of those were really what I wanted or could afford.
So being the geek that I am I started doing some research on how the guys over at nanocustoms/nanotuners put together the ICA Nanochiller, which doesn't seem to be for sale anymore.
The ICA (and the iceprobe) both use TEC or Peltier units for cooling the water. If you're not familiar with the TEC/Peltier concept, check out the Wikipedia entries on Thermoelectric Cooling and the Peltier Effect.
Essentially the TEC is a little device that you pass electricity through and you end up with a cold side, and a hot side. The cold side can get REALLY cold too. These little units are used for cooling lasers, lab equipment, popsicles, etc.
I did quite a bit of research on these. My biggest hurdle was figuring out how to pass water over the TEC. The Nanocustoms guys were using cpu waterblocks, and an annodized aluminum "back plate" that the TEC cooled. I even found a post from one of the nanotuners guys in a corrosion engineering forum on the effects of saltwater against annodized 6061 aluminum.
Most CPU waterblocks are made of a cast plastic, or annodized aluminum, with a copper "cold plate". The problem here, is that if the annodization isn't PERFECT, you can wind up with little exposed bits of AL, when salt water is passed over these bits of AL, it corrodes. AL comes in various formats, but nearly ALL of them have some copper in it. And copper is bad to get "dissolved" into your tank!
Most of the oceanic corrosion people I spoke with (one is an uncle-in-law who's done some consulting for the Shedd) suggested I use Titanium as a cold plate.
Wow. Titanium. TI is EXPENSIVE stuff, and it's awfully hard to work with w/o the proper tools (of which I have none) or the proper skills (of which I have very little).
If all these terms are getting confusing, here's a pic to help explain how these are normally put together:
Click for full size
So my compromise for the cold plate area was to use Acrylic. Now Acrylic doesn't transfer heat very well. It's actually a fairly good insulator. So I'm going to need to be able to put some serious cold against this thing to make much of a difference in water temprature. The NC guys are using a 78W unit for the ICA, I need something bigger.
After doing some additional digging, I found some 138W units for sale on ebay that are the same size as the 78W unit over at NC. 40mmx40mm. This allows me to use the ICA waterblock to handle the water.
As for the heatsink, I didn't have anything on hand, but I did have some store credit with Fry's. I stopped over and found a cheap chipset cooler from Thermaltake called the "Crystal Orb", this little unit has a fan built into it. I'm not sure how well it'll work to be honest, but at $9.00 what the heck. I later found some old CPU heatsnks from a Pentium that I can use if the orb can't keep up.
Anyway, here's what I've built so far:
Side shot:
Click for full size
What your looking at here, is the completed unit. There are two peices of acrylic 1/8" glued together with weld-on #3. the piece closest to the heatsink has a hole cut in it large enough for the peltier to fit through, and the bottom piece has been routed down to about 1/16" thick around the peltier unit to get it as close to the water as possible.
Top:
Click for full size
Bottom:
Click for full size
The heatsink is held on with some thermal grease, and zip ties. I'll find something more permanent once I figure out if the Orb can handle the heat produced by the TEC.
The plan is to mount this in my hood above the return chamber, and use a small pump to push water through it.
I've still got some work to do. I'm performing a leak test this afternoon, and I plan on powering it up with a couple of 12V 1A "wall wart" style transformers. The TEC is rated at 12V/10A max current draw, so my little 1A unit isn't going to cut it for long, but it should be able to provide me with a proof-of-concept run and cool some luke-warm water.
One of the things that the ICA and IceProbe units lack are temprature controllers. The units are always "on". I don't really care for that much, especially since the current draw on these is pretty high. A little more research netted me a nifty little microcontroller called an "Arduino". This is like, the coolest thing ever. Easy to use, easy to program, and cheap. Just the way I like it.
I picked up an Arduino, a monochrome LCD, and thermistor "SparkFun". I also picked up some relays and other misc components from Mouser. I plan on embedding the thermistor in some airline tubing and epoxy and sinking that in the water. From there I should be able to sense the temp of the water and toggle on/off the TEC and heatsink fan, and the pump that will push the water through the waterblock.
I'm still waiting on the parts for the microcontoller. But I wanted to get this first part out there while it's still fresh. I'll post more once the microcontroller shows up.
I've been having a problem with my BC29 overheating after I retrofit a 150W MH into the hood. Temps in the unit shot up to 87 at one point (yikes!).
Click for full size
So I decided to do a low-tech approach and install 4 80mm fans into the hood in the "doors" of the BC29:
Door #1 in the front:
Click for full size
Door #2:
Click for full size
And it helped, quite a bit. I'm peaking out at about 81 degrees now, which is still too high for my taste.
So it's time to do something a little more drastic I think. Now chillers IMO are awfully expensive. I started looking around a things like the Ice Probe, and the mini chillers from JBJ, etc. But none of those were really what I wanted or could afford.
So being the geek that I am I started doing some research on how the guys over at nanocustoms/nanotuners put together the ICA Nanochiller, which doesn't seem to be for sale anymore.
The ICA (and the iceprobe) both use TEC or Peltier units for cooling the water. If you're not familiar with the TEC/Peltier concept, check out the Wikipedia entries on Thermoelectric Cooling and the Peltier Effect.
Essentially the TEC is a little device that you pass electricity through and you end up with a cold side, and a hot side. The cold side can get REALLY cold too. These little units are used for cooling lasers, lab equipment, popsicles, etc.
I did quite a bit of research on these. My biggest hurdle was figuring out how to pass water over the TEC. The Nanocustoms guys were using cpu waterblocks, and an annodized aluminum "back plate" that the TEC cooled. I even found a post from one of the nanotuners guys in a corrosion engineering forum on the effects of saltwater against annodized 6061 aluminum.
Most CPU waterblocks are made of a cast plastic, or annodized aluminum, with a copper "cold plate". The problem here, is that if the annodization isn't PERFECT, you can wind up with little exposed bits of AL, when salt water is passed over these bits of AL, it corrodes. AL comes in various formats, but nearly ALL of them have some copper in it. And copper is bad to get "dissolved" into your tank!
Most of the oceanic corrosion people I spoke with (one is an uncle-in-law who's done some consulting for the Shedd) suggested I use Titanium as a cold plate.
Wow. Titanium. TI is EXPENSIVE stuff, and it's awfully hard to work with w/o the proper tools (of which I have none) or the proper skills (of which I have very little).
If all these terms are getting confusing, here's a pic to help explain how these are normally put together:
Click for full size
So my compromise for the cold plate area was to use Acrylic. Now Acrylic doesn't transfer heat very well. It's actually a fairly good insulator. So I'm going to need to be able to put some serious cold against this thing to make much of a difference in water temprature. The NC guys are using a 78W unit for the ICA, I need something bigger.
After doing some additional digging, I found some 138W units for sale on ebay that are the same size as the 78W unit over at NC. 40mmx40mm. This allows me to use the ICA waterblock to handle the water.
As for the heatsink, I didn't have anything on hand, but I did have some store credit with Fry's. I stopped over and found a cheap chipset cooler from Thermaltake called the "Crystal Orb", this little unit has a fan built into it. I'm not sure how well it'll work to be honest, but at $9.00 what the heck. I later found some old CPU heatsnks from a Pentium that I can use if the orb can't keep up.
Anyway, here's what I've built so far:
Side shot:
Click for full size
What your looking at here, is the completed unit. There are two peices of acrylic 1/8" glued together with weld-on #3. the piece closest to the heatsink has a hole cut in it large enough for the peltier to fit through, and the bottom piece has been routed down to about 1/16" thick around the peltier unit to get it as close to the water as possible.
Top:
Click for full size
Bottom:
Click for full size
The heatsink is held on with some thermal grease, and zip ties. I'll find something more permanent once I figure out if the Orb can handle the heat produced by the TEC.
The plan is to mount this in my hood above the return chamber, and use a small pump to push water through it.
I've still got some work to do. I'm performing a leak test this afternoon, and I plan on powering it up with a couple of 12V 1A "wall wart" style transformers. The TEC is rated at 12V/10A max current draw, so my little 1A unit isn't going to cut it for long, but it should be able to provide me with a proof-of-concept run and cool some luke-warm water.
One of the things that the ICA and IceProbe units lack are temprature controllers. The units are always "on". I don't really care for that much, especially since the current draw on these is pretty high. A little more research netted me a nifty little microcontroller called an "Arduino". This is like, the coolest thing ever. Easy to use, easy to program, and cheap. Just the way I like it.
I picked up an Arduino, a monochrome LCD, and thermistor "SparkFun". I also picked up some relays and other misc components from Mouser. I plan on embedding the thermistor in some airline tubing and epoxy and sinking that in the water. From there I should be able to sense the temp of the water and toggle on/off the TEC and heatsink fan, and the pump that will push the water through the waterblock.
I'm still waiting on the parts for the microcontoller. But I wanted to get this first part out there while it's still fresh. I'll post more once the microcontroller shows up.
.Seems like after 3 moves the copper heatsink and my peltiers have disappeared.So since it looks like I have to start from scratch,I figured I would go a different route and try to help you in the process.
