R22 vs R404 differences

[heatkaft]

So I recently started working for my father, who sells walk-ins and condensers. He said R22 refrigerant is starting to become phased out because of the increasing cost and harm to the environment so he said he is going to stop selling R22 and move to R404 instead.

I'm just wondering, what are the main differences (if there are alot) between R22 and R404?

[Six]

Off the top of my head, 404a is a blend not compatible with mineral oil. Runs at lower pressures and can fix capacity issues in old systems.

Not a drop in replacement.

[jpsmith1cm]

Off the top of my head, 404a is a blend not compatible with mineral oil. Runs at higher pressures and can fix capacity issues in old systems.

Not a drop in replacement.

That's what you meant to say, isn't it??

R-404a has a higher saturation pressure for a given temperature than R-22 does.

404a will tend to run a cooler discharge temperature, though.


I do believe that it is a better refrigerant.

[icemeister]

Off the top of my head, 404a is a blend not compatible with mineral oil. Runs at lower pressures and can fix capacity issues in old systems.

Not a drop in replacement.

I believe heatkaft is asking about R22 vs R404A more in terms of how they compare when used for new installations rather than as replacement refrigerants.

BTW..., if you check your PT chart you'll see that pressures are a bit higher than R22 at the same saturation temperatures.

The primary driving force to cause a switch from R22 to R404A in commercial refrigeration system today is probably cost. As the cost of R22 increases, the price of R404A has come down significantly. Many of us in this business made that decision some years ago simply because R404A is in many ways a much better refrigerant.

One very big plus is R404A runs at much lower discharge gas temperatures, meaning the compressor and its oil are a lot cooler at the same conditions. That translates to greatly improve compressor life expectancy since the oil isn't being cooked to the point of breaking down and slowly killing the compressor.

Another advantage is R404A works equally well on low, medium or high temperature applications...so one refrigerant for all. I like that immensely.

[timtech6408]

R404 is a better A/C refrigerant because of the lower temps but works like R410 in heating. The discharge temps are lower than the normal for what an R22 system would see. The new dry R22 units have mineral oil in them so they are already compatable with R404. Many are starting to use that since the price of R22 is getting bad.

[heatkaft]

Looks like I have a lot to learn because I didn't understand most of what you guys meant but I guess I did notice that R404 is used for cooler and freezer condensing units but I haven't seen any R22 freezer units yet.

[icemeister]

R404 is a better A/C refrigerant because of the lower temps but works like R410 in heating.

I don't see where you're coming from with this info. Could you expand on it a bit so we understand?

The discharge temps are lower than the normal for what an R22 system would see.

This is true.

The new dry R22 units have mineral oil in them so they are already compatable with R404. Many are starting to use that since the price of R22 is getting bad.

Didn't you mean to say they contain POE oil? Either way, not all dry units are currently being shipped with POE (which is compatible with R404A).

But one issue I see with what you suggest is no manufacturer of dry units (that I'm aware of) has approved R404A for use in their units...ie, no warranty.

Another thing I'm concerned with is how would you properly select the expansion device required? For example, if the system has a fixed orifice, the orifice flow capacity must be nearly double that of R22...and I doubt there are any charts out there to tell you the right one to use.

I would think a much better solution for dry units with R22 compressors containing POE oil would be to use R407C as long as the manufacturer allows it. I know that R407C is now an approved R22 substitute in dry units from Nordyne...there may be others.

[jpsmith1cm]

Looks like I have a lot to learn because I didn't understand most of what you guys meant but I guess I did notice that R404 is used for cooler and freezer condensing units but I haven't seen any R22 freezer units yet.

R-22 in a low temp application isn't the greatest match.

It will work, but it has some issues, namely high discharge temperature that can lead to oil breakdown.

R-404a has been used in low temp applications for quite some time, now, so I don't expect you'd see too many R-22 freezers.

[barbar]

R404 is a better A/C refrigerant because of the lower temps but works like R410 in heating. The discharge temps are lower than the normal for what an R22 system would see. The new dry R22 units have mineral oil in them so they are already compatable with R404. Many are starting to use that since the price of R22 is getting bad.

If the dry units have mineral oil, then the units are NOT compatible with R404a.

[Six]

That's what you meant to say, isn't it??

R-404a has a higher saturation pressure for a given temperature than R-22 does.

404a will tend to run a cooler discharge temperature, though.


I do believe that it is a better refrigerant.

Yep sry. It was off the top of my head with out referencing a PT chart. I was multitasking at thw time as usual.

[jdwendling]

Ice is right as usuall R404 for all. I thought that us Ref. Techs had it all sorted out R404 would be our refrigerant!!!! But Iv'e learned that the big BOX stores (WM) are requesting R410 A So Copeland is complying and doing the work to supply Compressors rated for R 410A service ( OH NO) I hope the coil manufactureres are able to comply also

[Six]

I believe heatkaft is asking about R22 vs R404A more in terms of how they compare when used for new installations rather than as replacement refrigerants.

BTW..., if you check your PT chart you'll see that pressures are a bit higher than R22 at the same saturation temperatures.

The primary driving force to cause a switch from R22 to R404A in commercial refrigeration system today is probably cost. As the cost of R22 increases, the price of R404A has come down significantly. Many of us in this business made that decision some years ago simply because R404A is in many ways a much better refrigerant.

One very big plus is R404A runs at much lower discharge gas temperatures, meaning the compressor and its oil are a lot cooler at the same conditions. That translates to greatly improve compressor life expectancy since the oil isn't being cooked to the point of breaking down and slowly killing the compressor.

Another advantage is R404A works equally well on low, medium or high temperature applications...so one refrigerant for all. I like that immensely.

No way to discern his specific intentions. I took the part about him just starting as a reason to give him general information.

Went off memory and didnt reference a pt chart or google. Guess Im getting old.

[craig1]

Ice is right as usuall R404 for all. I thought that us Ref. Techs had it all sorted out R404 would be our refrigerant!!!! But Iv'e learned that the big BOX stores (WM) are requesting R410 A So Copeland is complying and doing the work to supply Compressors rated for R 410A service ( OH NO) I hope the coil manufactureres are able to comply also

410a would allow significantly smaller pipe sizes which would decrease both the cost of the copper and the refrigerant to fill it. I can see why they want to investigate 410a for refrigeration.