450W isn't your heatload, I'd really be surprised to hear what you think will get you that high. Not to mention a Chilly1 really starts to suck it above 250W or so. Holds to 300W okay.
And you really can't predict. -30C If you tune well?
The difficulty is not only in parts selection, but tuning becomes incredibly hard. The tinyiest effect on stage one turns into a huge effect down the line in the second stage. It's a balancing act. And dealing with high pressure refrigerants like ALL low temp ones (for 2nd and 3rd stages and such) require a great knowledge of what your doing, pressures can go VERY high.
Also, is it simple to take the refridgerant out? Or do i need a car repair place to do it?
Have a few more questions...thanks a ton for answering all these noob ?'s i reaaly appreciate it.
For oil i was going to use mineral oil because from what i heard that is compatible with propane. So could i just put in jhonsons baby oil? Or does it have to be some kind of industrial grade stuff?
Does the oil have to be "compatible" with the compressor or is the compressor only made to handle certain lubricants?
Can any compressor take any refridgerant? Or is there some kind of limiting factor that wont let me throw propane into an a/c unit?
Sorry for mispellings...i wrote this on my ipod
With a rotary, removing the oil is not easy. The system of a rotary requires you to drill through the top of the compressor to get half of the oil out. Just flipping it will only yield you the other half in the pan. Propane and other hydrocarbons are compatible with all oils. And Jhonsons baby oil is not suitable, you don't know what else is in there and it's not made to the same specification, or weight, or expansionary weight. (Think engine oil where it has a room temp and load temp volume).
Compressors can handle almost any refrigerant with the proper oil. However they cannot handle all pressures. R410a will kill most compressors quickly as the higher discharge temperatures and pressures do immense damage.Edited by NoL - 7/12/09 at 11:31pm