Stewie's Chiller Revision 3.0b Build :)

[n00b 0f l337]

Wait did you paint insulation foam?

[teyber]

5 hours later and its still tacky. I guess its not fast dry paint, hehe. Its drying to a more deep blue than the picture looks; although I did use a flash; it was dark.

hey, if you have a heat gun i would start using that. when 5 hours has passed and its still not dry in my experience it won't ever dry as its not sticking tot he thing your painting... i would hair drier that.

beautiful paint though

[Stewie007]

Wait did you paint insulation foam?

What's wrong with painting insulation foam? They do it on industrial units that hardly anybody will ever see. At Carrier, we paint ours grey. Prime, then paint; it doesn't fall off.

hey, if you have a heat gun i would start using that. when 5 hours has passed and its still not dry in my experience it won't ever dry as its not sticking tot he thing your painting... i would hair drier that.

beautiful paint though

Actually, today I came home to a nice glossy dry paint. There was minor tackiness in very few spots, but no paint came off, and I pressed somewhat firmly. I let it dry over night; it'll probably be fully dry tomorrow morning. And it still looks very much like the picture.

On another note, I brought home some loctite 554 from work today; it works way better than teflon; hehe. Its a good refrigerant sealant; if any of you don't use it, you should.

[bassie]

hey, if you have a heat gun i would start using that. when 5 hours has passed and its still not dry in my experience it won't ever dry as its not sticking tot he thing your painting... i would hair drier that.

beautiful paint though

It depents on the paint, most of the paint i have needs 12+ houres to dry.

Stewie, nice smurf color

[Stewie007]

Well this is just metalic exterior paint from Lowes, painted over a black primer. It is designed to dry without any special curing or heat.

I should have a little time to work on it this weekend, at least to get the brazing started.

[Stewie007]

Work has been sluggish, however I've assembled the evaporator side and brazed it. I'll have pictures later tonight, not much really. Just the compressor and applicable piping.

I leak tested this portion of the system from the rota lock to the TXV already by closing the valve to the compressor, and capping off the system on the opposite side.

The refrigerant loop is holding 300PSI steady for a week now. No leaks.

The water side held 50 PSI for equally long.

No leaks so far.

[Stewie007]

Alright, as promised, a few pictures of the rig so far. Its holding steady.

Just a pic from above, and one of my handiwork.

[Stewie007]

Alright, I got back to work today. I gotta say though, for some reason the condenser loop wouldn't fit the way I put it together last time. I guess I couldn't remember how I laid it out LOL. So I changed it up a bit.

Below you can see that I elevated the condenser on a platform made of a 3x3 block of wood. Attached is a metal piece that I wraped in insulation tape, cutting it, and making it look UNsloppy. Its screwed and glued to the wood base below.

I acquired a 3/8" cutoff valve for the condenser side as well. This way, I can fully isolate the compressor from the loop if need be by closing the rotalock valve and the ball valve on the high side. I still havent installed the equalizer tube.

After brazing the assembly, while purging with nitrogen, I tested the sucker to 300PSI. After equalizing the system on both sides of the TXV to 300PSI. No leaks!!

[Stewie007]

After much ado with the chiller loop, it was then onto the water loop. Alas, we encounter another difficulty in the design. Because the design changed in the way the inlets and outlets were run for the refrigeration loop, the chilling pump no longer fits into its side without interfering with other parts of the chiller, or in the future; other parts of the enclosure. Try as I might, I couldn't figure out a way to incorporate the monster into the design.

So I came up with a different solution. Given that this monster is a VERY high capacity pump, it wouldn't matter where in the system it was. So I designed a pump station for the chiller pump to reside. The condenser pump may later migrate to the same area, however, currently, I believe I'll keep it integrated.

The cooler pump relocation will involve a few changes in tubing design, but nothing that I would consider critical. The pictures below show the basic structure of the pumping station as it will be. Note that I rotated the impeller housing 90 degrees for a horizontal discharge.

Now is the annoying part. At some point in the past, a plastic... *shakes his hea* .. yes, a plastic piece on the impeller busted off. This part encased the impeller shaft, and would keep the impeller spinning true....However, now I have to replace the impeller assembly or get a new pump. I think little giant sells replacements..... No big deal, but it puts a slight hitch in the operation. Anyways, other than that, nothing else new. The wind chased me inside finally, and that is all .

[n00b 0f l337]

Truly beastly, hell of a pumping setup.

[Xeon th MG Pony]

Firstly, albeit late I'll comment on the paint, Usualy if it is cool out paint will take longer to dry, when doing heavy paint jobs I use chilled paint in my air brush, gives me longer working time to get the right adhearing and mixing effects, once compleated it goes into a warmed drying booth at 21c with a low volume fan to keep the air churning.

Secondly now: That is a low temp compressor! it is designed for a low SST so for a chiller I suspect many a head ach to come! (As another poster stated he had issues with starting, that is becuase he was using a wrong compressor with wrong equipment) For that you will need a CPR and or a MOP TXV and run it at well below 0 say -20C, and a pump down cycle is strongly if not flat out mandatory recomended!

Thirdly, the HXs, By your law's the vessels will have to be Hydrostaticly tested, you can do this with a greas gun and refrigerant grade Mineral oil, and test to 1000 psig, if all your brazes are good it will hold that no prob and they do look well don. Infact if you work for Carier their techs may be able to do it for you! That way you'll get a certified stamp on them!


Other then the fiew warnings and sujestions your project is looking excellent!

[TopherTony]

I worry about the heat that pump is dropping into the loop. Also, depending on the pressure it exerts, the tubing you try to run from the chiller to the blocks might not hold, unless you decide to plumb the entire loop, a PITA I wouldnt want to imagine.

How does that pump compare to an IWAKI RD-30 at 24V?

[Stewie007]

@Xeon: Yeah, I do have some...... concerns about whether the compressor would work appropriately. I bought it knowing it was a low temp compressor, so I didn't just randomly select it on ebay, hehe. Its rated operating range is from -10 to +20 degrees F.

However, on the operational side, I am not very experienced. I have a vague understanding of most of this stuff, since I haven't every been on the test stand at work, hehe. That's what I'm doing here . So you'll have to help me, I'm don't completely understand the concept of a pump down cycle.

@Tony: Actually, I am counting on the heat from the pump to give me a better delta T. It'll almost act as a cooler heater, but not attached to the cooler. I tested it on my previous chiller to assertain the level of added heat. After running for 30 minutes, without running any type of cooling on the loop, the water was slightly warm. With a chiller on the loop, the pump won't be able to get as hot.

The piping will be mostly that up to the connections behind the desk. This is where it gets tricky. I am still not certain of how I am going to do this. I need the computer to be able to slide out on the slider so I can make adjustments, or connect and disconnect things. Flexible tubing is one idea, but then there is insulated rubber hosing. With a 0.5" ID, I could run it without worries. The inside connections are still not even drawn out. I am not even certain what kind of block I am going to use. But the piping, eh Im not worried. It will take time, but shouldn't be a huge headache.

As for the pump, it is three and a half times more powerful. However, that comes at a cost of using 4 times more power.... Probably overkill, but oh well, I already have it. hehe.

[TopherTony]

as far as a cpu block, I would recommend either MIPS, from Germany, or Apogee GTX with the addtional copper top. Replace the o-rings and you should be good.

[Stewie007]

as far as a cpu block, I would recommend either MIPS, from Germany, or Apogee GTX with the addtional copper top. Replace the o-rings and you should be good.

That's right, the GTX is all metal. I'll have to get some gasket material to replace the o-ring. It would be nice if they made the full coverage "stealth" for ATI graphics cards though. That would be super nifty . Although, I don't think I'm gonna chill the graphics car. I think I'm settling on just water cooling for the graphics cards. No need to put THAT much hardware at risk :p

[Xeon th MG Pony]

for a pump down cycle you need a low pressur switch, it attaches to the suction line, and you need a liquid line solenoid valve.

Once your set tempriture is reached the liquid line solenoid (LLS) Closes (Gets de-energised). The LLS is controlled by your loop thermistat.

The compressor is cycled via the Low Pressure Switch (LPS), When the LLS is closed it begins pumping the refrigerant in to the Condenser, as it does this suction pressure will drop, once it gets to around 5-6psi it will cycle the compressor off, and set the difrential to 5, so when the pressur raises to 10 it will turn the compressor on to bring it back to 5psi.

This way the compressor can start with next to no load.

Ask the techs at work to explain it to you further if there is still confussion.

Now with that you have to use either an MOP TXV or a CPR to prevent compressor over loading.

[Stewie007]

Edit: Actually, thats more like a set-up on a brine chiller.

What type of electrical controls do I need? It sounds likely to be expensive.

More to the point though, why is pump down essential?

[Stewie007]

By the way, what is a MOP TXV

[Xeon th MG Pony]

it is essential in order for the compressor to start unloaded, and as for parts all you need is a normaly closed solenoid valve and a Low pressur cut out switch with an adjustable range, one would immagin you all ready posess a therma stat, it is that which will control the Solenoid valve and the Low pressure cut out will control the compressor.

MOP stands for Maximum Opperating Pressure. It is a form of TXV that will regulate the suction pressure, you can use such a valve or you will need a crank case pressure regulating valve (CPR) In order to not over load the compressor. If you do not use these systems you will have many start up issues and possible compressor failure.

[Stewie007]

Well, I don't have a thermostat yet... I'm just in the building phase. I'm saving the complicated stuff for last :p

But I can't seem to find any MOP txv specification in any refrigeration store catalog. So how do I know if its MOP or not.

[DetroitAC]

Check the Sporlan and/or Alco websites. Sporlan will put a P in the code for a charge mead with a MOP, and sometimes they have different MOPs that you can select. You have to have their catalog to know what to ask for at the refrigeration store. If you wander in there and ask those guys to tell you what you want...they'll think you want what is on the shelf and easy for them!

I agree with Xeon that a low temp compressor isn't appropriate for a chiller. My guess is a medium temp, too lazy to look through the thread to see how cold you're going...

[Stewie007]

So when you say crankcase, THIS is what you're talking about, right?

So if I get one of these, I get a LPS and a solenoid valve, and some controls, and thats it?

I wanna do this right... and if it means adding trinkets here and there, so be it.

[Stewie007]

When I went to the refrigeration store, they put one together for me. Unfortunately, I guess it was wasted money :p

[Xeon th MG Pony]

Yes thats the valve you need, or a MOP with the CPR you do not need an MOP, with out an MOP you need a CPR.

The MOP will be tuned for the opperating SST of the compressor as it will not allow the suction to go above the compressors opperating pressure

[Stewie007]

The Max operating pressure of this compressor is 150 PSI........

I guess I'll get a crank then... but I still need the switch right?