Overclock.net › Forums › Cooling › Specialized Cooling › Phase Change › (UPDATED) 3.2 kw chiller unit as a school project
New Posts  All Forums:Forum Nav:

(UPDATED) 3.2 kw chiller unit as a school project - Page 2

post #11 of 45
Thread Starter 
im not worrying about high temps on anything sinse this thing is going to be outside under a roof in norway now it is -12C below frezzing i am more worried about not getting egnought head pressure xD also this will not be super chillin this wil hold a watertemp of + 5 to - 5 and maybe sometimes go supercold like -30 or somthing but im not worried about the winding varnish this is going to get cooked the windings are rated to 300 C + in working conditions before it starts to take damage i know this becuse my dad was working on rewinding everything from small motors to 200MW ones insanly huge but they all used the same varnish wich is super strong. im more worried about an oil problem and head pressure issues of being to low but thanks for the advice anyway biggrin.gif just to say we have had an heat pump a ductless split one thats bien run for 3 years constantly and we have had it for 6 years we dont use it alot in the summer time but it has never broke down even at temps as low as -25C they just never die thumb.gif also aslong as you have a good airflow over the compressor that will also help alot of keeping the stator packs cold wink.gif. also i run this when it was still an aircon at tems as low as -40 the comp discharege stayed cool and the pressure was not bad either but it was around 100 psi...isj damn brain xD but now im going to take a weekend brake and play skyrim smile.gif also btw im not worried about compressor overheat AT ALL cus there was almost no superheat at low temps. this will be run in a cold enviorment be aware of that and it wil be not run at long peripds of time just to say thumb.gif
post #12 of 45
A couple options for raising head pressure during cold ambient would be, installing a head pressure control valve(Headmaster) and or a fan cycling pressure switch. The Headmasters can be quite expensive, you should at least add the fan cycling switch. I recommend a switch adjustable from 100-400psi with 40-150psi pressure differential. Look for Ranco or Danfoss.

The high pressure cutoff for your application with r410a can be 350-400psi. Use a manual reset type.

You don't need a huge receiver.. 30mm x 300mm is fine. If copper costs too much then use a steel pipe rated for the pressure.

A 50 plate hx is fine. Oil won't be a problem in the -30c range. If going lower then add a small amount of propane to facilitate oil return. You can go ahead and add it either way.. the small amount won't hurt anything. Just pre-charge to 40psi with propane "gas".. the rest r410a liquid.

Note.. you'll need to run a methanol blend for the coolant when operating that low in temp. You can run a non-flammable mix up to around -30c.. after that it needs more methanol to keep from slushing/freezing. Iwaki or Little Giant pumps can handle the fluid and temps perfectly fine. I use Prestone De-Icer washer fluid to -30c. PEAK is another good brand.
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
post #13 of 45
Thread Starter 
well i got a frequency controller for the fan so that it will variate the fan speed and not just on off but is it ok to run a 50 plat hx botom to top for the rifrigirant so it will have time to boil off withot a oil sep cut its so DAMN expensive 450 bucks mad.gif then 25 precent tat upon that agein tis is going to cost me a kideny tongue.gif lol but the reciver diamiter is hard to get small pices off copper and also steel mad.gif but my dad is looking if they have any at work they got copper and stailess steel pipes i think so ill ask if i can have 40 cm of pipe and endcaps is no problem its just to run to the stor and get some thumb.gif and for a pump i will use a grundfoss pump like this http://www.plumbcenter.co.uk/en/heating/pumps/grundfos-magna-upe-25-60-speed-circular-domestic-bare-pump-1-ph-62508 that will do the trick smile.gif but i want to run bottom to top without an oilsep will save me alot of money and hassle if its safe tho thumb.gif
post #14 of 45
I wouldn't allow pressure that high Drew unless hes using a retail receiver rated for that pressure. 300 to 350 psi is adequate for his needs and shouldn't be an issue for his homemade receiver.

Just my 2 cents...
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
post #15 of 45
@SD...The main reason I suggested a 350-400psi cutoff is because all the r410a systems I've worked on had discharge pressures well above 300psi. If CS can keep discharge pressure below that then all the better. Maybe use an adjustable cutoff switch and start at 300psi .. increase if needed.

I did take into consideration the smaller diameter tubing of 30mm/1.125". The working pressure for 30mm drawn copper is close to 900psi... annealed from brazing process is still well over 500psi.. burst pressure will be many times that. The end caps of course are the weakest link.. but at approx 1in² the force applied is still only 350-400psi. The problem is when ppl start to use much larger diameter tubing and improper end caps. I always keep the receivers thin(1.125"OD) and tall... if they need to be short then I'd use a retail unit.

CS.. that's great you already have a frequency drive there. Hopefully it will have quick enough response time during starts. The slightly higher hpco might be needed in this situation. A fan cycle switch can still be incorporated as a backup to prevent excessive pressure spikes.

You won't have any problems feeding the 50 plate hx bottom to top at -30c. Obviously the system will be capable of temps below that so I highly recommend the shot of r290(propane) regardless. Keep the suction line 3/8"/9.5mm and incorporate a nice size "u" bend to help meter off excess liquid. If you only need occasional sub -40c use for like pc benching then I wouldn't worry about an oil separator. Just cycle the compressor with pump off every few hours and the velocity/elevated temps will carry the oil back to the compressor.
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
post #16 of 45
Maybe start at 300 to 350 psi and if its not tripping on a regular basis then great otherwise adjust it up to 400 - 450...

No biggie either way..
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
post #17 of 45
Thread Starter 
THANKS for all the tips i can get a 400 psi cut out for cheap so i think im getting that since its 10 precent of a ajustable one. also do i need high qualety propane or can i use regular sulphur added propene aka BBQ propane. the freqency controller is 3 phase like what the hell a 2 amp 3 phase fancontroller like sometimes i really hate 3 phase mad.gif so i cant use that but ill get a danfoss 3 amp one later for about 200 bucks thumb.gif but its a good thing i dont need to use an oil sep tongue.gif also PROGRESS in sheet metal


and here is the berginnings of the front shroud for sound insulaition biggrin.gif I LOVE METAL ITS SO EASY TO WORK WITH


and for the back of the case


condenser and fan secured with screws biggrin.gif 6mm from fanblade to condenser so im happy with that, moves **** loades of air wink.gif


also heres my braizing joint you think it looks ok


and heres an aditionai 24 7 chiller with a sc12dl comp in the making im painting the case black as you can see but i need to clean the compressor out with some oil since its bien exposed to the elements for 2-3 years but no rust inside the comp and it functions alright so il just flush it with oil a couple of times and hopefully that wil be ok rolleyes.gif



thats all for now and thanks agein for all the really great tips its really helping me out here smile.gif
post #18 of 45
Nice metal work there CS! Do you have a shear and brake?

That's too bad about the 3 phase controller. We have opposite situation at my work.. we now need 3 phase controllers and have a bunch of single collecting dust. rolleyes.gif

The braze joint looks ok.. just a bit lumpy. Just so you got some to flow down into the joint. It's all about preparation and heat control.. a good quality filler rod helps too.

No fan shroud for the condenser? The fan bracket screws are nutted I hope.

Are you going to add a reservoir?

If you're adding a solenoid valve then make sure to position hpco after the condenser.

You can clean the Danfoss out with mineral spirits too if you like... just make sure it all drains out and evaporates.

Any propane will do... I use Coleman camping fuel or Bernzomatic for torch.

Is the 24/7 chiller for pc then?
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
GRX
(13 items)
 
  
CPUMotherboardGraphicsRAM
Phenom II X4 965 @ 5.7Ghz Gigabyte 890FXA-UD5 XFX HD 5850 1160/1200 vmods -15c 4GB G-Skill Flares PC3 16000 
Hard DriveOptical DriveOSMonitor
WD Caviar Black 1TB Lite-On DVDR Vista/XP Acer 23.6" 
KeyboardPowerCaseMouse
MS Ultra 750W Benchtop FTW! Logitech 
Mouse Pad
Walmart Special 
  hide details  
Reply
post #19 of 45
Heh very nice work there. I just ordered a pan break and shear for the holidays, so excited.
post #20 of 45
looks large enough for two compressors a 20 plate hx and an oil sep...
hmmm
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
My System
(15 items)
 
  
CPUMotherboardGraphicsGraphics
i5 2500k Biostar TZ77XE4 6950 6950 
RAMHard DriveCoolingOS
8gb - DDR3 main: 120gb SSD 830 + 3 1tb drives Air Win7 
MonitorPowerCase
3 x DELL ST242OL  OCZ 900W Lian-Li Custom 
  hide details  
Reply
New Posts  All Forums:Forum Nav:
  Return Home
  Back to Forum: Phase Change
Overclock.net › Forums › Cooling › Specialized Cooling › Phase Change › (UPDATED) 3.2 kw chiller unit as a school project