R408a

[sdumper]

How does R408a compare to R507? will the temps be nearly identical in most builds?

Also what advantage would I have of using one of these more expensive filter driers over the spun copper which I have been using:
http://www.under-the-ice.com/index.php?cPath=31&osCsid=b60bccd2216918377513696e91094707

Sorry for all the questions guys but there is so much to learn :)

[[XC] gomeler]

I've used both types of filter/dryers and in short, the spun copper with valve combination is far superior in usability. It reduces the number of brazes and components needed and has enough desiccant to be effective in systems as small as ours. I have yet to have an issue with a spun copper filter dryer, I'm sold on them :up:

On R408a, it has a higher vaporization heat but a warmer boiling point and nearly identical liquid density. Cannot find it's vapor density but I suspect it'll be ever so slightly lower than R507. So in short, from what I can understand, R507 will boil slightly lower but remove ~10% less heat in delivering identical quantities of gas. You've already got R507 though so I wouldn't worry about another 1st stage gas :shrug: This is all from a basic understanding of refrigerant properties, I'm sure someone else can drop in and give a proper answer

[sdumper]

Thanks Chris!!

[DetroitAC]

The best way IMO to compare two refrigerants is to simulate a simple cycle using the same conditions. The reason is that two refrigerants may have properties slightly better, and slightly worse than the other so you need a cycle to sort out the effects.

I chose a very simple cycle in the range of a single stage, and assumed that both machines need to provide the same cooling power at the same temperature.

R507 has a 16% higher COP
R507 has a 3% lower Pressure Ratio
R507 has an 8% lower volume flow of suction gas

For all of those are parameters R507 is better :up:

[sdumper]

Super thanks!!