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06-24-2004, 11:19 AM
How is it for r-12? Just found out about it and thinking of ditching 409. Any sugestions?

gbfromsd
06-25-2004, 01:17 AM
I have an account at a VA hospital here. All their walkins are on FR-12. No problems there.

Use 416 all the time on 12 changeouts often, works just
fine. 2yrs now and all my soldiers are still marching.

edward301
06-25-2004, 04:19 AM
Have some old Singer 20hp reffer units. Recently
changed out compressor and put r416 in.

Works great, and runs at lower pressure.

taylortech
06-27-2004, 04:47 PM
Use it all the time on med temp boxes. Unsure about low temp.

06-27-2004, 06:11 PM
We use it place of 134 from time to time. Better head in confined spaces

R12rules
06-27-2004, 06:40 PM
Originally posted by lusker
We use it place of 134 from time to time. Better head in confined spaces

Now what do you mean by better head?

Presure is nothing I am concerned about. It's the temperature I worry about.

Inquiring minds want to know....

R12rules
06-27-2004, 07:01 PM
If the stuff works, well ... then it works. And that's nice.

But the question of how well it works in comparison to what we have in other blends of "blends" .... it may not meaure up.

I dug out my PT chart for this blend and found that at a 15F evaporator, which is where your gonna be runnin' your walk-in boxes at.... Good Ol' R-12 is displaying a back pressure of 18 PSIG back pressure.
For 416 to be at 15 degrees, we will display a backpressure of 10 PSIG.

Hmmmm.... from eighteen pounds down to ten pounds back pressure.
Hmmmm..... does the term; "Volumetric Effeciency" come to mind here?

Let's look at the head pressure for 100 Degree liquid temp.

R-12 would be around 118 PSIG head pressure and 118 divided by 18 is a ratio of 6.5 to 1.

Now with 416 we have 114 for our head divided by 10 for our back pressure which equals a ratio of 11.4 to 1.

Hmmm.... 6.5 to 1 versus 11.4 to 1 ...... hmmmm.... this blend requires almost forty percent higher compression ratio to do the job as Good Ol' R-12 did.

Now before I begin sounding like an engineer here ... like discussing piston clearances in the head and re-heat/re-compression of gasses ... perhaps somebody can look up in some chart and discover how effecient this blend really is.

Cause with the math I just performed ... it appears to me this stuff wont work nearly as well as Good Ol' R-12 did.

06-27-2004, 07:39 PM
Let's see, if the winds come from the North East at a flow rate of 10 to 18 MPH while the sun is rising in Texas on a rainy day at 9:30 am we can reduce our head condensing TEMPERATURE by 8.3% but only on the third Thursday of the month.

This is why we like to use it on 134a cap tube systems with a 16 or less oz weight charge boxes that are in tight and scary places with little or no air flow.

Remember, we charge to superheat and subcooling, not to weight, head or suction pressures!

Now if you do the math with a 120* condensing temperature and a 8.3% reduction in heat that is only 9.96 degrees. If I can keep a good liquid seal, coil frost down to a minimum with and possibly increase of compressor life... I'll take every degree I can muster.

And.... if we are low on truck stock 134A but have plenty of R416 on a weekend night... then we trip over this fact by accident and it worked. Well....

I still don't like blends, never have, never will. Give me back my R12 and R502. I hope no one here really believes that we are creating a world catastrophe. Or that man is so bold that he thinks he can change the world climate with a little CFC or HCFC.

icemeister
06-27-2004, 07:52 PM
Good point on the pressure ratio, but if you're calculating it you have to use PSIA values and not the PSIG. With the example used, if you add 14.7 lb/sq in to each and redo the math, the ratios are now 4.1 and 8.8.

R12rules
06-27-2004, 11:17 PM
Lusker, I never bought into that crap about ozone holes in the first place.

In fact, I advocate we all stop using the blends altogether and go back to using only the originals!

The hell with the EPA and the Montreal Protocol!

I say we all get our butts up in the morning and drop off our blends at the shop and pick up ... by whatever means we deem possible/profitable ... and pick up some Real Freon. Then we sell it to our customers! And we dont sell them nothing but the real thing anymore!

And all we carry on our trucks is12, 22 and five-o-two. Just like in the old days.

So ... Lusker, if you think YOUR WEIRD .... move over buddy.

Lmtd, so your saying that 416 is not a good replacement for 12 based upon the compression ratio math?
That's what I thought.

I never did that math before. ... I just happened to be in an awnry mood so I went for it.

:p

dchrbac
06-28-2004, 11:51 PM
Ive seen they are selling automotive cans of freon that say "Freeze 12". Anyone know if this is 416? Just curious.

rocket
06-29-2004, 02:36 AM
Freeze 12, yes it is R416
R416 was originally developed for Automotive use
The auto industry didn't adopt it, now they are selling it to us. It has shown mixed results.

Copeland, Tecumseh and Carlye only approve the following blends for R12 replacements:
R404A MP-39
R401B MP-66
R409A
that's it!
You can use whatever else you wish, but you are on your own

superfittertech
07-02-2004, 09:31 PM
rocket not R404A you must mean R401A

rocket
07-02-2004, 09:40 PM
sorry,
typo error
MP39 is R401A
Thanks for correction