Doing it again :) 2x 2.5HP cascade - worklog

[piotres]

Hi

I'm doing it again - this time 2x 2.5HP cascade, without case, without optional adds, just pure power (I hope it'll be powerful ).

Specs :

compressors: HIGHLY (Hitachi) CTHU333WC6-U - R407c, 28488 BTU. 48.8ccm each - 2 pcs
evap: steeper 54mm
XV: captube 0.9 mm / captube 0.9 mm (on both stages)
HX: plate HX , 30 plates
condenser: 4.8 Kw, alu-cu, cooled by 2x 254mm 230V EBM fans
refrigerants : R507/R1150
oilseparator : Shine Year automatic
safety : 2x RANCO cut-offs (one to each stage) with manual reset, Torrecilla 6.0l expansion tank
case : Black metal baseplate
others: -

Work done till now:













































To be continued ...

Regards
Peter

[Patrickclouds]

holy crap. never seen so many things done wrong.

use copper fittings for size reduction and don't crimp a 16mm t-piece to 6mm schrader connector or the rest of you pipes
did you drill the filter drier for connecting the shrader and the captube for high pressure cut off switch? a t-piece dosn't cost that much but looks more proper.
you shouldn't connect a security relevant component with captube.
now i understand why you polish your evaps because you are using phosphor rads instead of silver.
the "anaconda" has no effect because you didn't fix the pipe.

don't you want to improve your skills? or is there some other reason why you always do things in the same wrong way?

[mytekcontrols]

holy crap. never seen so many things done wrong.

use copper fittings for size reduction and don't crimp a 16mm t-piece to 6mm schrader connector or the rest of you pipes
did you drill the filter drier for connecting the shrader and the captube for high pressure cut off switch? a t-piece dosn't cost that much but looks more proper.
you shouldn't connect a security relevant component with captube.
now i understand why you polish your evaps because you are using phosphor rads instead of silver.
the "anaconda" has no effect because you didn't fix the pipe.

don't you want to improve your skills? or is there some other reason why you always do things in the same wrong way?

Hmmm... looks like someone had a bad day or something.

Yes the vibration eliminator should be clamped at the HX side to be most effective, although I wouldn't say it has "no effect" without it. It just isn't as effective.

Edit: With such a short connecting tube running between the vibration eliminator and the plate HX, there really isn't a need to clamp the tubing since the HX represents a pretty solid object.

The only concern I would have with drilling into the side of the filter dryer and then brazing would have to do with heat possibly damaging the desiccant inside. Other wise I don't see it as looking improper, in fact I think this build looks very nice indeed.

The use of a cap tube to connect a high side pressure switch I know is extremely frowned upon by organizations like RWTUV, but the use of 1/4" (or similar metric size) tubing instead, ends of usually cracking over time due to vibration (happens all the time on Polycold's CE units). In tests that I helped conduct, when using a medium ID cap tube such as 0.042" with several loops and the same in 1/4" od copper tubing, neither would protect the compressor from blowing reed valves if the compressor discharge were blocked downstream. And when dealing with a normally escalating discharge pressure due to over charging, failure to buffer, or no cooling water, both solutions were deemed equally effective at shutting down the compressor in time before any damage could be done. The idea of introducing a delayed reaction with a cap tube on a pressure switch is highly overrated unless one were to use something extremely small or very long.

I love the extremely well polished evaporators

This build is looking great!!!

[ryba]

holy crap. never seen so many things done wrong.

use copper fittings for size reduction and don't crimp a 16mm t-piece to 6mm schrader connector or the rest of you pipes
did you drill the filter drier for connecting the shrader and the captube for high pressure cut off switch? a t-piece dosn't cost that much but looks more proper.
you shouldn't connect a security relevant component with captube.
now i understand why you polish your evaps because you are using phosphor rads instead of silver.
the "anaconda" has no effect because you didn't fix the pipe.

don't you want to improve your skills? or is there some other reason why you always do things in the same wrong way?

Well, I don't see it the same as you. His build working? Yes, it is. Your projects are done maybe more pro, but working so/so. Piotres 1:0 Patrickclouds.

[runmc]

Thanks for sharing your project Peter. I hope this machine is a winner for you.

[piotres]

holy crap. never seen so many things done wrong.

use copper fittings for size reduction and don't crimp a 16mm t-piece to 6mm schrader connector or the rest of you pipes I prefer to crimp it and make 1 brazing point, than two (two if I use reduction). I crimp pipes and braze in that way since longer than 5 years and almost none of mine units have a leak so - it works . So why I should change it ?
did you drill the filter drier for connecting the shrader and the captube for high pressure cut off switch? a t-piece dosn't cost that much but looks more proper. same as above - more brazing connections = more possibility for leak - it I use "T" 1/4 for shrader I must make 2 brazed connections more, if also another "T" for safety device pipe - total 4 points more . Plus lenght of part shrader+drier will be MUCH longer . As You can see there isn't much free space on baseplate.
you shouldn't connect a security relevant component with captube.
now i understand why you polish your evaps because you are using phosphor rads instead of silver. And ??? So what rods You use to braze cooper to copper ? I've tried more than 5 types of rods and those which I use currently work the best IMO for copper. "Few" units done using those rods and - no leaks .
the "anaconda" has no effect because you didn't fix the pipe.

don't you want to improve your skills? or is there some other reason why you always do things in the same wrong way?

I've answered You in Your quote (bolded).

Thanks for all nice comments.

[Patrickclouds]

@ ryba

All my units work very well if you mean temperature and load. Haven't had a single complaint or defect unit. Not one broken suction line.

There are different engineer standards you have to follow. In our case it is the electronic and refrigeration engineering. If you decide for your own not to follow them it is up to you but my life is too short to make any compromise. I do it in the best way.

When you take a look on the receiver you see that there is no rotalock valve. It is not alowed to braze on a pressure container like you did. You cannot sell a unit that outrages againt so many refrigeration engineering standards.

I use 55% silver rods for evap brazing, because you don't have to heat the evap that much. --> less oxidation

evap without polish:


reduction t-fittings:


more fittings: oh and look, you can insulate phase seperator without using armaflex tape.

[piotres]

I purge mine evaps during brazing so they are 100% clean inside. And outside - why just not to clean and polish it after brazing ? it's simple and quite fast work so I do that.

Sorry, but IMO Your evaps without cleaning and polishing don't look good.

I don't prefer silver rods, I've 2 leaks in mine units since I make them, and both were on connection of copper to steel, where I use 45% Ag rods with flux. IMO 3-5% phosphor rods works much better when we braze copper to copper than 40-55% Ag rods.

[runmc]

I use Dynaflow

Silver not necessary IMO.

[Buckeye]

Peter you make really beautiful units

I have one of your evaps on my rig and it was really nice to get that and look at it, almost made me sad to actually use it HAHA
The your big 54mm steppers are just so nice. Someday I wil get one of those beasts

[piotres]

Update.

All is already brazed.







Plus some electric done, but only to prepare the unit for loadtesting .





And some "final" electric. No more chineese switches (too much problems with them and they are not trustworthy). Now I use only Arcolectric (England).

[mytekcontrols]

Coming together rather nicely

Peter --- just curious as to what you have in mind for insulating your flat plate HX. Will it be inside a polyurethane foamed enclosure, or just be armaflex covered?

Hey those new rocker switches look like something I've used before made by Cherry (Allied Electronics p/n 70207306, MFR p/n WRG32F2FBGLN)

[piotres]

HX will be just covered with armaflex.

[piotres]

That should had been a worklog, but ...I hadn't got time to upload pictures .

Unit is already finished .



First charge.



CHY shows -120



315W loaded with "cloth" insulation.







Clear coat on polished pipes.













1st stage unloaded on CHY (-60*C).



2nd stage unloaded on voltcraft (-107*C).



Loaded with 315W after 4 hours test (-103*C).











Finaly finished .





And almost ready to go.

Regards
Peter

[mytekcontrols]

She's quite the beauty!

Looks like it's working great
And I love the logo!

[sdumper]

Piotres I really like this build.

Question though. It seems like a bit of overkill using compressors that large. Do you see any gains in load handling?

[piotres]

In fact, gain of performance under load by using 20k+ BTU compressors isn't big. In this cascade I make -103 on mine 315w dummy, to compare cascade with 8-10k BTU compressors make -86 to -89C on the same dummyload (http://www.piotres.com/?go=1,index,000044,value_cascade,). Nevertheless I think that 18k BTU compressors will be enought to get -95C to -100C@315W in mine case (of course I've written about R407c rotaries).

Here mine another cascades and temperatures on main page to compare: http://www.piotres.com/

Those 315W dummyload kicks units' asses much stronger that mine previous 260W dummy .

[almighty15]

Peter - another epic build log

[sdumper]

In fact, gain of performance under load by using 20k+ BTU compressors isn't big. In this cascade I make -103 on mine 315w dummy, to compare cascade with 8-10k BTU compressors make -86 to -89C on the same dummyload (http://www.piotres.com/?go=1,index,000044,value_cascade,). Nevertheless I think that 18k BTU compressors will be enought to get -95C to -100C@315W in mine case (of course I've written about R407c rotaries).

Here mine another cascades and temperatures on main page to compare: http://www.piotres.com/

Those 315W dummyload kicks units' asses much stronger that mine previous 260W dummy .

Good to know thanks

[piotres]

Movie on Youtube:

http://www.youtube.com/watch?v=zbcJw...1&feature=plcp

[-cyclone-]

Great job piotres! I like your painting style -)

BTW what is the actual life resource of properly built rotary units of this type?

[piotres]

The oldest units made by me are approx 5 years old, and till now I've replace only one rotary compressor in "mine" cascades. I hope that is good answer for Your question .

[chaotic]

Very beautiful work

[M.Beier]

3730W on the compressors, aaaargh!!! Thats 'a bit'

Crazy project!!! Great result, trying to figure how much 315W is on computer hardware, got a feeling this is going to do graphics.

[piotres]

Power consumption of that unit is "only" 2200-2800W .