keep it on ice for life!
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keep it on ice for life!
Moisture is you enemy. Insulate,insulate,insulate and when your done insulate more...
chilly1 i wish you lived close so we could turn my prommy into a mod'd monster
hey Chilly,
Why you dont name each parts in those pics? That whould be great...
I think it is obvious skate2snow ;) get a cataglogue from ur nearest refrigeration specialist and everything will be catagorised in there.
He draw it to explain people, if people didnt understand how to loop a cascade, they probably dont know what each parts are...
Don't see why any temperature is great as long as the insulation is goodenough to keep the moisture from condensing on the components.
What is a TXV and how is it different form a cap tube?
I work at an automotive garage and we use soemthing called an orafice tube thats only about 2 inches long, is the TXV similar to that?
No a txv is what is on the higher end auto's Some use an expansion block, like all things automotive they rename it change the fittings to something no one else has and charge fifteen times the cost. The oriface tube is a fixed metering device that also includes a debris screen, this is simmilar in action to a capillary tube, theere is also an after market expansion tube that will meter the flow of refrigerant depending upon the entering temperature, so it will restrict the flow the hotter the entering refrigerant is. I had a 69 Mecury Montery 429 2brl, it had an R-12 AC with a 3 ton TXV The sensing bulb strapes on the suction line exiting the evap. The bulb senses the line temperature and restricts the flow of refrigerant if it gets too cold but this is depending on pressure.
Whats too cold? IS their anything where the user adjusts it, or does it just know?Quote:
The sensing bulb strapes on the suction line exiting the evap. The bulb senses the line temperature and restricts the flow of refrigerant if it gets too cold but this is depending on pressure.
also
is your website up? you seem very knowlegable and willing to help others understand, just wondering if it is up if their are any guides or nething.Quote:
Retawi@cox.net my addy.... got anything you need... working ona website
Thanks in advance.
Well the drawings are a good start and if you have questions PM me. Or email me and I will help you build your own. You can set the superheat with the TXV.
Three stage...
hmmm guess that answers my question about a reciever when using a CPEV....
Only need a very small reciever too large and the system volume of high pressure gas will be too high.
Why arent oil seperators used on the first stage of these systems, or on single stage systems? Is it just a matter of cost? Wouldnt the condenser and hx be more efficient if oil was seperated in the first stage, or is there a performance hit by adding one?
Regards
John.
At higher than -50 temperatures the oil returns well enough and if you have oil that will remain miscible to -100 while remaining viscous enough to lubricate the compressor then for systems within those temperatures then you would not need an oil separator. Although you would gain from the use of an oil separator on the single stage compressor it would be only 1 to 2 degrees at most. The addition of oil solvents with vapor pressures higher than the suction pressure is sometimes used to facilitate the return of oil in cases where there is no oil separator and where a small amount of oil may bypass the oil separator.
I think I understand that, are you saying there would be a small gain, because heat transfer would be better at the condensor and hx as the oil wouldnt act as a barrier to heat transfer between the refrigerant and copper transfer vessel. Also are you saying that there is no disadvantage?
Regards
John.
There is a little disadvantage when the float lets the oil into the compressor, but not much other than the additional cost of construction.
Is an interstage HX the same as a shell and tube HX, or are they different. Also what does the reciever in picture 1 do? Is it mjust a holding tank?
Same, There are two recievers they store the liquid that has comndensed in the condensers but hasn't moved on to the metering device.
Is that like what an accumulator does with gas, or is that not what an accumulator does?
No an accumulator is where the liquid that did not boil off in the evaporator is trapped.
Ahh, ok, so is an accumulator or a reciever essentally a tank, or are their more parts to them?
An accumulator has a u shaped pipe in it with a very small hole in the bottom for oil pickup. A reciever also has a dip tube in the bottom of the tank so the oil will go out with the liquid refrigerant.
If you have an oil separator in your system do thses still trap oil? I thought an oil separator separated it all and sent it back to the compressor?