Is there a 502 replacment drop in?

[refermadness]

Hi all,
I have an old Hobart reach in freezer that just isn't getting down in temp like it used to. Nothing is iced up, all coils clean, fans,and compressor running. Guages say its running at about 5psi suction. I think it is slightly low on charge. Nameplate says 502 , I don't have any. I was wondering if I evac the system find the leak and repair it, what refrigerant could I put into this freezer without having to change the oil and filter driers? Thanks for help-refermadness

[wambat]

Yes, 404a, you will use about 10% less refrigerant in the system

[Blaster]

Yes, 404a, you will use about 10% less refrigerant in the system

404a needs POE oil

if you can replace some of the oil with AB oil you could use r402a

think would be the best solution

[Peter_1]

Why not simply add a drop-in like R408a?

[refermadness]

Thanks for replies. So which refrigerant should I use? Everyone had a different answer. A drop in replacement is preferred. Thanks again

[Temprite]

Peter has the right answer.

Use 408A.

Then you dont have to change the oil.I have done it many times.

[Andy T]

Isceon 69l drop in.

[Raven]

Hi,
Drop in for R502.
R408A
R402A
R402B
R403B
HP80
HP81
69L
Dont forget to change the drier,
Hope this helps,
Cheers,
Raven

[wambat]

I invite to go here and notice the lubricant recommended. As you are in California this should be easy to obtain It's called R422 or MP79
http://refrigerants.dupont.com/Suva/.../isceon79.html

Benefits


provides easy, quick, cost-effective retrofits—easier retrofit than R-404A and R-507
non-ozone-depleting HFC
in most cases no change of lubricant type during retrofit is required -- compatible with traditional and new lubricants
enables continued use of existing equipment
20% lower Global Warming Potential (GWP) vs. R-404A and R-507
can be topped off during service without removing the entire refrigerant charge

[refermadness]

Hey thanks for the feedback I think I will go with the
408A as I have a jug of it on site. I have a ton of different refrigeration equipment in my building that I am responsible for maintaining so I am sure you will be hearing from me again. Thanks again refermadness

[Toolman]

Yay the R408 won in the end , you can put it on top of the remaining R502 as well you know , it saves trying to do something with the "reclaimed " gas afterwards .

[Toolman]

Hey thanks for the feedback I think I will go with the
408A as I have a jug of it on site. I have a ton of different refrigeration equipment in my building that I am responsible for maintaining so I am sure you will be hearing from me again. Thanks again refermadness

Why do we have all these new gases available especially when you consider a lot of them contain much the same (R134 in R404)
Could it not be possible to the manufactures to standardise gases or is it just a ploy to have lots of them & keep the price up
Regards
Raymond

When ozone depleting rules kicked in about all it did was give those clever marketing people an opportunity to market yet another product . In Australia there's MANY MANY gases avaliable most of them do the same job , and are probably the same gas underneath . We just make all new jobs R404 . Retro refits are just with the drop in gases R409 & R408

[John Wood]

Definately R408a, it is very happy with mineral oil, however I would not mix it with R502!!!!!!

BTW, Whats the point of using a drop in refrigerant if you have to change to AB oil, it's not really a drop in then is it?

[saud khan]

hi
the best is use 408a if you have a site glass just charge it till it is clear

[tommy 1234]

i have a freezer that takes r-408 but i have alot of r-502 can i mix the two together???

[tommy 1234]

what will happen if r-502 and r-408 are mixed together there is only a ten degree difference in the refrigerants

[Peter_1]

r408a is a drop-in, the name says itself. , sure you can.

[chillin out]

I have always used R408, just fling it in on any R502 job on top of the remaining gas and oil.

Chillin

[powell]

R408A, as the others have noted.

[thebigcheese]

i use 408 but call it 69 is it the same thing???

[powell]

i use 408 but call it 69 is it the same thing???

Isceon 69 is R403b.

[Peter]

Hi,
Drop in for R502.
R408A
R402A
R402B
R403B
HP80
HP81
69L
Dont forget to change the drier,
Hope this helps,
Cheers,
Raven

In 18 months time you won't be able to use virgin product of any of the above in Europe, however the DuPont ISCEON MO79 replaces all of them.

[WINJA]

Isceon 69l drop in.

Have to agree , ive used lots of 69L in everything from blast freezers to small display cabinets with no oil change

[koh]

Hi!,

Best drop-in solution to replace R502 is DuPont Isceon 79. Most cases no oil change required.

Regards
Koh/Singapore

[al595017]

Hi, Can drop ins be used the other way round? ie can R408a be used to charge a R404a sytem if no 404a is readily available? What would be the effect on system?

Thanks

[lowcool]

the new refigerants react with the old oils,r22 is an example as works with poe & mineral oils

[cadwaladr]

thanks for replies. So which refrigerant should i use? Everyone had a different answer. A drop in replacement is preferred. Thanks again

69l works ok for me

[al595017]

Hi!,

Best drop-in solution to replace R502 is DuPont Isceon 79. Most cases no oil change required.

Regards
Koh/Singapore

Any advice available?
According to the makers Isceon 79 is better than R404a in some applications so would I be right in thinking that it could replace R404a? If so would it be a 5% less charge as suggested for retrofitting R502, R408a etc or the same charge as R404a?

Thanks

A

[lowcool]

408 for me works fantastic on medium temp too.go the croweaters

[davids2212]

hi
i had a job today with a foster freezer! it had no refridgerant in it but needed r502. i repaired the cabinet and then filled with r408a but the temp went from +22C and fell and sat around -1C !!!! have i got a control problem? HELP please!!

[saud khan]

need to know more about the cabinet is it control by expansion valves or capalary

[Andy T]

What Are the gauge pressures.You probably only got Suction connected.Chances are you have a low suction pressure.
Reasons:
Weight of charge incorrect
Moisture in system.Is the suction going into a vac and then shooting back up Again.
Blocked dryer. or capalary
Are the fans running.The tempurature won't drop until the Evap is cold enough to start the fans.
It could be lots of other things but we need more info from you.
I use R69L for a replacement for R502
Worked perfect in everything I used It In.

[davids2212]

I have only been doing this for three months so any help is much appreciated (passing C+G 2079 doesn’t make you a fridge engineer!!!) Got to play with the freezer for a couple of hours today! From previous engineer documentation back from 1993 they filled the freezer with 450g of r502. I put in 300g of r408a today and the freezer sat a –11deg C. low pressure reading 1.8 bar and frost build up on low pressure (suction) side before compressor (have I still over filled it?). The defrost heaters are not stuck on, good air flow, fans working and new door seals. Ladies in the canteen told me that the freezer always had a problem reaching temp and from when I first got the job there was a lot of ice build up on the evaporator.

it uses capalary and i do only have the suction line connected but it doesnt go into a vac and shoot back up it stays quite still at 1.8 bar!

will R502 still work or do i need to get R69L


Please somebody put me out of this misery, what have I missed!

[Andy T]

Engineer log.Nice.Sounds to me that you need to find the data plate on the room.It should have the refrigerant and weight of charge.Also check the comp for a match to the old gas.I would trust that more than the Engineers log.I charge the same amount of 69L as on the plate.If you do that correct.Then you can rule out it's somthing you have done wronge.Also with frosting on the coil and the unit never before working well.You should be looking for faults for that too.These faults can be tricky to find.Your at -11. thats better than yesterday.
I would charge it with another 150g.If it starts frosting back on the suction bad.Then I would double check the airflow.Fan rotation.Blocked air flow(boxes blocking intake,Panel put back wronge or missing)that sort of thing.
If it has never worked right.Is it really a freezer box,or has someone decided to convert it. or just set the temp down.Being on R502 suggest it is.but look at the name plate.there are two ways to find a fault.
No.1 First look for the fault.
No.2 Check everything to see if it all working correct.and stumble on the fault.Starting with the most likely.
You have only been doing it for 3 months.Call your boss and ask for onsite help on this one.