pelt cooling that is not that cool.....
 

ok so i got my first water cooling system going, and i am dumbfounded as to why my water/pelt block is not near as cold as i thought it would be. it does stay a good 15 degrees F (9C)cooler than ambient (being at 75-ish F / 24-ish C) besides having 1.) a small hole in an approx. ~8" X 11" (~20cm X 28cm) radiator 2.) massive air bubbles in the whole loop, 3.) via aqua 1300 pump, and 4.) a 220watt peltier with an antec true430 all to itself (about 75%-78% powered)....what could be the problem?

i plan on getting a a nice 5" X 5" X whatever" all copper heater core when i get to working on it again. i will also try to prime the whole system with no air in the loop and see if that makes a different.

i'll post picts of the block, as well as the whole system (funny stuff!) that i am using when i get home.

How low do you want your temps? Frankly a 220 should get you 15C below ambient. Think you may have a dud tec? I had a 68 Watt tec and it sucked. It wasnt labeled properly. You sure thats a 220?

Another question.. why dont you have an air trap to get rid of those bubbles? That would really bug me.

Your heat isn't exiting the system nicely, creating high temps everywhere.

1)clear up the area to allow the core (which one?) to have more airflow.

2)get an airtrap (a tee will do).

3)measure the voltage at the TEC, and figure out its power usage.


It's usually not terribly difficult to figure out where most of the heat is being trapped: either your water's hot, or the air through the rad is (usually both). Your water temp will be a good indicator.

@winewood
i was expecting my tec to do like -20C with no load on it. i purchased the 220w at BeCooling here im not sure of the deltaT on it (i know, should have sourced it out better, but i was ignorant at the time of purchase)

as for the air bubbles, it was a test run to see what would happen, i plan on having a nice stainless steel reservoir at the top of the system with a nice small screw on cap for just that problem.

@bigben2k
the core of the proc is the one in the sig, JIUHB 0302 t-bred b xp1700

the air-trap issue is covered above

i will measure the voltage tomorrow, right now im just getting settled back in at home from 3 days of gdc goodness


ps:i know its a crude system, and its pure water in the system and yellow bottle, not actually antifreeze...

ok lets try posting this again...

AHAH!!

When my rad fan is off and no air flows through my radiator, the temp curve goes down to 15C then back up slowly as heat cascades into the water and isnt released. Without a fan on your setup, your pelt will fight a loosing battle. Once you get that taken care of, the pelt will overcome the barrier and do well. Remember to put thermal paste on your tec and sandwitch it good and tight between the copper blocks. If it's loose, you will loose some efficiency of the pelt.
Add a simple desk fan to blow through the radiator. It will allow the tec to go much cooler. So, bigben is right as usual.

In my previous post, as to the 15 below ambient.. i meant.. If the tec was good, you would have NO problems getting below that mark.

ok thank you winewood, ill see what a 18 inch room fan can do for my temp improvements tommorrow :D

Hey Tim,

Looks like you're on the right track... :)

Another suggestion: Get rid of the flow meter (if you really have to have it, put it on the discharge side of the pump - you don't want anything restricting flow on the suction side). With good air flow moving thru your radiator you should be able to see -20 to -30 C on the cold side (depending on how cool your ambient air is).

Good luck,

ok well, havent touched the system since the first time i posted...

the reservoir is in the works, gonna be a nice piece of 4" stainless steel pipe with some really pretty end caps on it. its gonna have a air-trap/fill cap and in and out barbs on it. expect picts soon

o and i noticed something about my block deign....i had integrated the peltier into the cold plate and i believe the heat is migrating around the outside of the pelt back to the cold side, kinda making a heat loop within the block. when i get a chance, i with take the current cold plate off, and make a new one.

i did go on a search for a nice 5" X 5" X 2" heatercore by using the heatercore db, only problem is that the one i want is the 2-563 its 76$ on the heatercore4u site, and kraigen quoted me at near $80 for it....wtf?? the other one i looked at is the 2-588 and that one is $73 on the heatercore site. im not gonna even bother getting a price on that one...

im gonna hit ebay and see what shows up

I say that HC is too small, especially if you decide to add more watts to your system in the future. Get the largest one you can fit.

Brian W

just got done with tweaking the system some more. removed the flowmeter, fully primed the system (no air in it at all!), put a big fan on the radiator on low speed, took the cold plate off and ran it with just the pelt thermal pasted onto the water block. and guess what? got some frost!!! i wish i would have taken a picture of it now...

@ben: as for volts/amps, something must be wrong with the amp part of my meter(only said it was getting 1.5amps) but the volts were in the 11.58v-11.87v range. on the label on the antec psu it says it should supply a max of 20 amps on the +12volt rail, so i dont know whats up with that

@BrianW: yeah i totally agree with you now. i was looking at a bunch of heatercores and looks like the prices significantly drop when i went looking for more common cores. the choise is either gonna be a 65-90 ford truck hc (6" X 6" X2") or a 82-84 chevy,oldsmobile,pontiac core (6.25" X 6" X 2") both of these look in the $25-$35 range. and another thing after looking at heater cores: those things are ugly looking. i found an old article on overclockers that shows how to clean and shine one up. so i will be polishing the new heater core when i get it and do a short leak test.

Yeah they are a bit ugly outta the box:

http://thengc.net/images/watercooled...odified_03.jpg

But you can get em pretty w/ a lil work....

http://thengc.net/images/watercooled...sanding_02.jpg

Can't wait to paint these babies...

http://thengc.net/images/watercooled...sanding_06.jpg

Brian W

very nice brian! i hope my can look that good. on the overclockers article, it assumed the rad was from a pick and pull, so the porcess included soaking it with bleach and hot water for like 30 mins, then using something like scotch-brite on it to shine it up. i have a scotch-brite wheel on the grinder right now but im kinda scared if that will rip it up rather than shine. only one way to find out :D

ok, so just another little update...

the cold plate has been replaced with something more flat. and it was siliconed up last night, so its curing at the moment.

still need to get a radiator. ive got a few more common and cheaper ones written down somewhere. gotta call around and see whats up.


so...this project may be getting put on hold due to my dads car being a prick (ive been borrowing it cause my car is out of commision) and ive gotten tired of dumping money into that pos. so i want to dump money into my pos and get it going again.