Quote:
Originally Posted by Matt L
I am talking about pressure-temperature curves and critical temperatures, and specifically not saying that you use the same quantity of propane as you would R12 or R134a.
Adding isobutane (R600a) reduces the pressure quite a bit. That's why it is added to propane. But any leaks will not leak the two gasses at the same rate, which is why it is not a good idea to top off a blend. You should always reclaim and recharge instead. Then dispose of the reclaimed refrigerant properly.
Now, I don't see anything in the EPA regulations which prevent me from disposing of such a blend in my backyard gas grill. Perhaps there is something there though.
|
I get what you're saying, but all I'm saying is, you will never see ridiculous head pressures because you're using such a greatly reduced volume of propane (or whatever other hydrocarbon refrigerant) vs. how much 134a is required.
Comparing the temp/pressure curves of each material is fine and dandy, but it pretty much goes out the window here, because you're only using 10%-20% as much hydrocarbon material as you would 134a, in order to get the same cooling efficiency. This will more than outweigh any differences in temp/pressure properties between the two. Your analysis would be completely correct, if you were using like quantities of each material, but you're not. A 2 or 2.2
pound 134a system will actually function better with just a few
ounces of hydrocarbon. You're never going to have enough volume in the system to create absurd pressures.