Miny Cascade : Budget Dual 1/2hp
So recently I had a few asks for a low budget cascade. Now normally those two terms can't be fit in the same sentence. Inherently, they are not low budget.
But sometimes exceptions can be made. And normally that requires a bit of sacrifice. But sometimes, just sometimes, you luck out :p
So, a miny cascade project. Dual 1/2hp 39R131F's from Rechi Precision.
Short toppers, and they run a bit hot, but they've never shown me less than there full 1/2hp :p
Condenser comes from a Copeland condensing unit (have about 20 of these things laying about, so time to use them).
Desuperheater is my new miny condensers, just under the dimensions of a 120mm fan, they're absolutely midgetish! Fitting a 120mm Panaflo 12G12L fan for good air flow with mid range noise.
Foam stack is the preinsulation first cuts for the 10 Plate HX. Which will be "bound" and insulated.
3ft flex line, Evaporator to be determined, and HPCO on the way.
The entire unit will most likely be cased in aluminum extrusion and acrylic/sheet metal to give it a solid indestructible approach. And of course I have a few other upgrades that can be fitted if the budget opens up a bit.
As for refrigerant,
R507a, R23 will be used.
Although not many builders can get their hands on R23 due to cost, I have a 10lb cylinder to be used, and it is much more ideal than trying to muscle R1150 to condense.
The goal will be about -70C, a solid dry ice range temperature, at the flick of a switchOf course unloaded will go lower for Spi etc giving that mid range bencher many are looking for to replace clumsy pots.
Hope you all enjoy this build as much as I do, I expect to be done with construction when the final parts arrive by next week (tuesdayish) and tune in the week after.
No owner on this one, so it might just go up for sale or just become a light weight show case.
52xx btuh 1/2hp Rechi. The specs on these might as well not exist. Finding the right run cap will be hard since I've found 3 conflicting numbers, will try them all after tuning and see which produces lowest power draw.
Progressing well, made the HX "box" from my favorite pink substance, and slot fitted the brazed and pressure tested plate HX. Using the mill I traced the ports and backside ridge into the foam. Snaps together, 3" thick, 10" tall, 5" wide. What a format.
Enjoy. Evap ordered from Ron. And searching up the HPCO now. I have some valve mount ones, but I raelly have grown to dislike them. Getting a stable long term seal can be a pain or just a general fight. Tho I could rip one off the 3 stager...
I'd recommend against R410a or R402a with these, they already run way to hot. I'm using r290 for oil, r507a primary, and already considering swapping to r134a if it'll do the r23.
As to some updates, first stage done, just need to tune when second stage is finished and ready for it. But we have frost! Amazingly she's quite quiet. Certainly can here it, but if you push down lightly on the HX box to muffle the vibration, there's not much but air flow noise. And speaking of that, this condenser setup's quite nice. I'm glad I went with the 13W motor on the fan.
I purchased a Supco vac gauge on ebay a while back, an old style one when my digital crapper out. It was sold as is, but at $25 it was hard to pass up. Even had a bidding war for it. But, I called Supco when I got it, told them I had purchased it second hand and wasn't sure if it was in Calibration.
They said send it over, so I did. They even paid return shipping. Recalibrated, all good now. Talk about great service, it's an old model, nothing close to there new stuff even.
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