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I should call this the 'miracle weight loss program' since that's what it's really about

So specs first...

120mm custom condensor
240mm custom condensor
(Edit - they're basically 3/4 of a 9000btu condensor, reworked for horizontal and vertical application. Should be 2/3 at least, so 6000btu or so total condensor capacity)
Custom shrouds
3/4hp Horizontal Tecumseh rotary
Piotres big stepper (old shape)
1 meter braided flex
Older Chilly1 case

So yeah, it's gotta be light.

Basically it might ship internationally and the whole 'if' is getting it under 20kg shipping weight. That's not so hard with some recips but Rotaries in this range are usually 15+kg and most I have are closer to 20kg on their own.

So I ordered in a horizontal after some questions about weight, and when it arrived it was exactly 11kg. Nice.

The case is a heavy steel, so I may need to start cutting 'blowholes' to save weight, but we'll see.

So far, assembled weight was 19kg. With gas, I know I'm starting to get closer to the 20 mark, but there's no holes for the top mount horizontal condensor.

I'm posting a few 'teasers' for now. It's gassed up and getting some nice results, but a couple guys were asking about 'custom' condensors and what I was doing. This is what I mean...










So I found the lightest steel I could find for the shrouds. They're strong enough, and really not carrying a lot of weight, but really weight is the issue.

The condensors are an ultralight type. Less than a kilo for both, including fans

the shrouds are a couple grams each. Only 22 guage.

Flexline and block add a fair bit, didn't weight those independently, but it adds up fast when your case is around 6+ kilos.

Otherwise it's 3/4hp performance so far. When I get a few more details done I'll post again.

It looks odd, but the compressor sits at a slightly upward angle.

The upper condensor is around 3/4" above the compressor when the case top is on and it'll screw into the top. Front condensor's shroud will get some 'speedclips' and then the screws will hold that up.

So a very 'specific' fitting, measuring everything so it's close. The pipes will give a bit of flexibility but it's got to be right or nothing works.

Oh, and the accumulator really IS that big. Odd looking thing, it's insulated in the pic with 6mm self adhesive neoprene but it's about 4 times the size of anything I've seen on an upright, or any horizontal for that matter.

So it's perfect for fitting again, meaning absolute PITA

This install is a 9" tall and wide case, and there's very little 'extra'.

May get a 200mm rear fan on it, but it's the weight. Not totally 'needed' but if I can it would really finish the back of it nice.

So that's basically what I mean by a custom condensor. having a bunch here means I can chop and braze almost anything and it's handy since getting someone else to do up a custom is a long wait or really expensive.

Have nooooo interest in making them all the time though. Takes a rod or two at like 5 bucks each (give or take) and the brazing, leaktesting, painting, and bending up a shroud is a lot of work, so here and there is fine but 'for everyone' there's just no way.

So I make 'em as it's needed but it's not really 'hard' just time consuming.

The shrouds and some other stuff still need more attention, but this is the basic idea. Been pretty neat so far, never had to get quite this picky before


There's a pic off their site. Shows the accumulator really well without insulation.




I measured well enough, it lined up enough to screw in the upper fan assembly and guards. Bit of clearance from the compressor so that's all good.

Well the final results are in

The unit runs just a hair warmer than with the case together, which is normal I guess. Airflow is mildly restricted with a case and I can't do a lot about that, but it's colder than I thought. I also need to increase the charge slightly, just to get it to cool down a bit faster. Static is 115psi now, still within a reasonable range.

Tuning is really odd. I left the last run of pipe uninsulated in charging tests and it frosts further with load than not. High side pressure pushing it further? Not sure, but it pulls back into the accumulator when it's unloaded. There's far more capacity than I can test now. It was holding 380w before the increase in charge.

The change to 50hz should be just fine now though. Estimate it at 400w+ at 60hz so 300w shouldn't be any problem with the slower speed if it affects it drastically.

Initially I was seeing -45c for a short load test, and if a person is benching with it on the shorter runs then I would imagine that's the kind of results you'd see. Increased charge brings it down a touch, but would rather lose a degree or 2 than not have full capacity.

For long prime runs and stuff, the longer load results are way more accurate.

So this is with the probe on the side under the heatshrink. It's a K bead probe so shouldn't see damage there. It's halfway down the evap, so not as close as I'd like but whatever. For a more true idea, I'd round down a little for a more 'evap base' temp.

406w -40.6


360w -42ish Sorry if it's upside down. Stupid imageshack


300w -43ish


200w -48 or so


100w -54


Unloaded after load tests -66c

Unfortunately 400w is the max my tester can do, and I had to turn off the heaters in the Garage to get that. The Garage power is only on a 30amp circuit and the load of everything pulls the voltage down a hair. Didn't really make a difference to ambient, especially with the phase unit acting as a heater
but I only turned them off for a final 'max load' test.

-40.6 at 406w is kind of funny
It was bouncing from 40.6 to 40.7 but I wanted to catch it there.

So I don't think this is a 3/4hp compressor. I mean, I've done what I can with the usual captube solder job and condensor's capable of maintaining the ambient even under load (tested at 23c ambient) but I didn't do anything fancy with Gas. R290 is becoming a favorite though. May not be as cold as some gasses, but it's so easy to keep the lowside pressure down that it's getting very good results with condensors that don't need to be as powerful.

I have to estimate closer to 1hp though. 16cc/64LRA doesn't quite sound like 1hp but bigger than 3/4 for sure, and the temps are too low for a 3/4hp unit.

For the versatility of a Horizontal Rotary though it's fantastic. Awkward, sure, but being able to use a large SS standard case is great. Very compact.

Noisy, well of course
it's a rotary!

So if anyone was thinking of this kind of thing, the minimum is a 9" wide and 9" tall case, but really to have 'good' room up top to do condensors then taller would be handy.

The Cooler Express (if it's 9" wide) would be perfect really. Tall enough for a lot of room.

If I deal with this kind of install again, I think that it'd be easier to do the top condensor setup but to fabricate a support bracket so that it was easier to install into the case top. It's not that bad, but a support would also mean it could work well without the case top on, and the temps are marginally better that way.

I'd have done the fan at the back but the room is really tight there too, and shipping could end up damaging it. So it's just open and Chilly1's old cases were very open so it's not too bad really.

That's that I guess. It's more or less ready to go at just barely under 19kg total weight, or around 42lbs.

I'll be packing it up and reweighing again, then I'll have to take it to the post office and get them to confirm that too. Once I can be 100% sure it's a 'pass' then I can go from there.

Working to that limit is tight for sure.

I think if I had a slightly lighter case it'd be easier, but at the same time the Chilly1 old case is seriously thick steel so damage won't be such an issue I hope. A lighter metal could get mangled on a long trip and that'd be a real shame.

Going to have to insure really high though, make sure that the cost of the shipping back again if they did do damage is definitely a good idea. Don't know if they'd just do it free and don't want to find out

So it's a success I guess. Mainly the weight really, over 20kg and it's not affordable to send overseas so I'm really glad I could keep that within the range.

The compressor was a pleasant surprise, though the strange tuning on it was a challenge. Judging by superheat wasn't really the way to go, more about max load and working down. Strange, but it's not flooding on max or no load so it's all good. Considering the price of the compressor was reasonable for a 3/4hp getting more than that is just a bonus.

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