R 416 A question ?

[mark 11]

Any body know where i can get information on
R 416 A refrigerant,my supplier at JS said this
refrigerant is not recommended for low temp applications,
want to read literature to confirm this information,
thank you........

[icemeister]

Go here for info on R416A.

A number of guys here use it and like it for medium temp stuff, but the only good interim replacement refrigerant for old low temp R12 systems is R401B (MP66).

[Dad]

They are right. It is not good for low temp operation.

The suction pressure at 0* is almost non existent and will not assist in compressor cooling.

Choose another favorite "blendito"

[mark 11]

Thanks for the info guys!

[redneck hvac-r]

Why 401 and not say 404? or 408? Just checking as I have never used this refrigerant...

Thanks,

Redneck.

[cyro]

I agree Redneck

Those are my freon choices.

[icemeister]

Neither R404A nor R408A aren't suitable replacements for existing R12 systems because their basic physical properties, not the least of which are their pressure/temperature characteristics, aren't even close to those of R12.

To retrofit an existing R12 system there are quite a number of options out there. However, To retrofit an existing R12 low temperature system R401B (MP66) performs the best.

[redneck hvac-r]

Do you change out the TXV on the system when you "retro" with the mp66?

That would be the only thing I would think would be wrong with the other refrigerants but I just do what the boss tells me too. I think that the type of refrigerant in the original system and the properties of the new would not be matched unless the type of oil is correct and you change the head on the TXV then check to see how it is feeding and adjust accordingly if needed.

Any thoughts? All constructive criticism accepted graciously.


Redneck.

[cyro]

Of course I would never use 404A,408A to replace r-12 in a system already in use.

That was not his question.

He asked for low temp replacements.

I use 404A in low,med,& high temp applications all the time. Last year I installed 50 remote cold well pans from Barker Mfg. We designed all of them for 404A, at 30*td on roof copeland semi cold zone units.

[icemeister]

Originally posted by cyro
Of course I would never use 404A,408A to replace r-12 in a system already in use.

That was not his question.

He asked for low temp replacements.

You are correct that the OP didn't specify that the question was about replacements. Since his inquiry was about R416A, I simply inferred that an interim replacement refrigerant was what he was after. My bad.

[basicelectromechanic]

We've been using 416 as an alternative to 12 for med temp commercial applications for a few years now with success.

Although many use it as an alt for low temp applications I personally don't care to operate with negative suction pressures. Fact is with small cap tube low temp machines the death sentence is usually fatigue induced evaporator failure, the leak that cannot be cost effectively repaired.

With more expensive commercial interim retrofit I usually change the oil to POE and run R134.( When capillary replacement is prudent )
On rare occasion I've used 416 in TXV application. ( When using a temp control that cycles evap temp ) because of the negligable glide. The change in evap op pressure does require superheat adjustment to balance operation ( flooding, poor capacity and low head without)

It seems every year there is less R12 equipment, soon it will all be in the boneyard or recycler and we won't have to worry about interims.

[k-fridge]

416 can be used for low temp application but you need to know this;

-There will be a slight capacity loss, so if you're marginal to start with you got problems.
-You'll likely run some negative suction pressures.
-In a TXV system the valve may require some significant adjustment to avoid flooding. Run the superheat on the low end of normal (6-8) for compressor cooling and to keep discharge temps down.
-If the system has much line run or compressor is above evap you should run AB or POE oil. I've had the best luck with AB in 416 applications.

As mentioned above, the best blend to replace R-12 low temp is MP66. But it has some problems in certain applications too. Some of the fractional compressors, especially normal starting torque won't handle it. And you need to run AB oil with it.