R404 or R408?

[jeffcolledge]

I'm installing a new air cooled 5hp outdoor condensong unit with capacity control tomorrow. It was originally a water-cooled 3hp unit, that had R408 dropped into it about 4 years ago. The condenser split and it's in a bad location, so I opted to go with an outdoor unit. It's the original txv, and I was told I could use R404 or R408. I would like some thoughts on which is better, I believe R404 is, but I'm trying to save the expense of buying a bottle, if the R408 will do. I will be using virgin ref as I already have a bottle of R408. Thanks.

[Dad]

Jeff,

If it was an old 502 system then drop 408 in it. If you use 404 you will need to change the oil in the compressor to POE. IF your area has a cold climate be sure to use a head master or a fan cycle control too.

Check here for the refrigerant info and your PT charts

http://www.refrigerants.com/frame.htm


funny, i just checked your profile to see where you are... forget about the cold climate remark... you know what to do

[jeffcolledge]

Hey Lusker...thanks for the reply
The compressor comes with POE oil in it already. The unit has all the bells and whistles for low ambient capacity control too. I was just curious what some guys thought was a better refrigerant and why!

[Dad]

Jeff,

Both, unfortunately, are blends. 408 and 404 are widely used by our company. As long as you check your PT charts, do your math on subcooling (on the liquid line) and superheat (at the evap) you will have no fear in using either.

Don’t forget, blends are not full sight glass charge refrigerants. If you have good readings just before off cycle you are good to go.

[mad_max3]

Why use 408-a. 404-a is a standard refrigerant now. If you use 408 you will need to carry around one more jug of refer and another recovery cylinder. Plus I have looked at three different P/T charts for 408-a and they were all different. If I had to replace 502 I would use HP-80. If I was putting in a new compressor I would go 404-a.

Hope this helps.

[2seasons-employed]

JEFF, IF YOU HAVE 408 YES IT WILL WORK, BUT I BELIEVE YOU WILL LOSE THE COMPRESSOR THE ONLY THING THAT WILL WORK WITH THE MINERAL OIL WILL BE HP 81, , THE COST OF IT HAS WWENT DOWN , AND IN COMPARISON TO 408 ITS MORE COST EFFECTIVE, 404-A HAS BOTH OF THEM BEAT COST EFFECTIVE WISE EXCEPT, THAT THE ONLY CONFRONTATION IS CHANGING THE OIL, DEPENDING ON THE AGE OF THE COMPRESSOR......COMPATABILITY WISE..YET THE TXV WILL WORK IN ALL THE 502 REPLACEMENT APP'S OR APPLICATIONS, YOOU CAN USE WHAT YOU WANT SINCE IT'S A NEW APPLICAATION/CONDENSING UNIT, LABEL IT FOR THE NEXT GUY, THINK SERVICE FRIENDLY, AND MAKE LOTS OF MONEY, DOING IT

[hvacmd2002]

R507

[condenseddave]

Originally posted by 2seasons-employed
JEFF, IF YOU HAVE 408 YES IT WILL WORK, BUT I BELIEVE YOU WILL LOSE THE COMPRESSOR THE ONLY THING THAT WILL WORK WITH THE MINERAL OIL WILL BE HP 81, , THE COST OF IT HAS WWENT DOWN , AND IN COMPARISON TO 408 ITS MORE COST EFFECTIVE, 404-A HAS BOTH OF THEM BEAT COST EFFECTIVE WISE EXCEPT, THAT THE ONLY CONFRONTATION IS CHANGING THE OIL, DEPENDING ON THE AGE OF THE COMPRESSOR......COMPATABILITY WISE..YET THE TXV WILL WORK IN ALL THE 502 REPLACEMENT APP'S OR APPLICATIONS, YOOU CAN USE WHAT YOU WANT SINCE IT'S A NEW APPLICAATION/CONDENSING UNIT, LABEL IT FOR THE NEXT GUY, THINK SERVICE FRIENDLY, AND MAKE LOTS OF MONEY, DOING IT

Turn off your capslock.

HP81 is a blend, sold in 13 lb bottles for use only in Manitowoc's out-of-production "B" series ice machine.

You might've meant HP80, which is a 502 replacement that runs a higher discharge temperature than 502.

408 is not only compatible with mineral oil, but is nearly identical on a PT chart to 502. It's disadvantages include higher cost than 404a, and the fact that it's scheduled for phaseout, just like R22. (The latter will make the former climb even higher in the near future.)

404A is an HFC, which is never scheduled for phaseout. It is an excellent choice for new installs, and is not really all that difficult to use during a retrofit such as this.

Neither 404, nor 408, or even HP80 will cause compressor failure. All are approved by the major compressor manufacturers.

Get your facts straight before making statements like:

Posted by 2seasons-employed

IF YOU HAVE 408 YES IT WILL WORK, BUT I BELIEVE YOU WILL LOSE THE COMPRESSOR THE ONLY THING THAT WILL WORK WITH THE MINERAL OIL WILL BE HP 81

That statement is incorrect, uninformed, and irresponsible.

The purpose of this website is to disseminate good advice, not baseless opinions.

Now turn off your capslock.

[gbfromsd]

Most definitely 404a whenever possible.
It's a win-win for everyone, including the environment.

[hvacmd2002]

I'm curious why everyone pushes 404a and not 507. 507 is an azeotrope, has greater capacity, and doesn't fractionate. So why wouldn't you use it?

[2seasons-employed]

Jeff, you dont have to change the txv like you said, and the new compressor should be labeled for the type of oil, 408 is more costly than 404-a, and you'd have to change the oil if it were the old compressor, and the hp-81 would work just fine to recharge the old compressor. but, since you sold them a new system to update their freezer, he he, use the usual 404-a standard, its more cost effective for you and the customer and user friendly to the general contents of a service trucks inventory. i want some of the profit, so why dont you just bill that in too, and if you need to know how to be more billable just ask mad max, he he he!

[2seasons-employed]

hp 81 no oil change for mineral! as for 507 i would have to check! but its not user friendly, Nobody carries it except for you , and thats the only reason , i wouldnt use it, lol! think about it "user Friendly" the golden rule!

[2seasons-employed]

404-a stinks and isnt easy to find a leak, yet it has a high head and breaks down WAX, the blend is all we got that is cost effective than other refrigerants. and is most user friendly by everyone... but dont make laugh with that enviormental win win , he he!

[2seasons-employed]

hey daazzle me with diamonds hp 81 try it u'll like in fact u'll love it, dont ass-ume!! live and learn mr facts, not just flat out attack others without the knowledge to back your beliefs, theres too many techs thaat think they have all the knowledge, and dont he he he

[2seasons-employed]

youre too funny i had read more , dont attach your beliefs to the manufacturer's specifications, lmfao,Neither 404, nor 408, or even HP80 will cause compressor failure. All are approved by the major compressor manufacturers. "all except for hp-81 according to diamond dave and his personal friends at the manufacturing plants, also, dave it doesnt take much more than 13 lbs for a small to medium application depending on the location or length of the line-set, or size of compressor,etc;, also dave read your charts 404-a will phase out...... they all will just like you! yoou are just full of yourself dave and your impolite answer or attack is irresponsible, and shows yoour inexperience! you treat me so bad since the baby didnt come?

[2seasons-employed]

all refrigerants can cause a compressor failure Get Your Facts Straight mr mouth, slugging, changing to a new oil,aafter years of the same use poor oil transfer with certain refrigerants, you know so much you could speed-dial the manufacturers to figure out hp 81 has mineral oil capability, "LET THESE TRUTHS BE HELD SELF-EVIDENT"

[smilies]

Guys everywhere feel the way you do until they get trained on how to do it right. Including myself.

[jeffcolledge]

Thanks guys...and er ..uh "2 seasons employed" for your responses!
I installed the unit today and used 404, almost a full jug!
It is working great. I'm going to check on it tomorrow just to confirm everything is working to the best of it's capabilities. I'm sure I'll have to add a "winter charge" when it gets cold out though. I recommend this type of unit. It's a Larkin and it comes with an oversized, insulated heated receiver, head master control, ll drier, sight glass, compressor contactor, defrost contactor, evap fan contactor, time clock, time delay relay for anit-short-cyle of the compressor and a nicely labelled terminal strip for feild wiring. You basically pipe in your liquid line and your suction line, some wire and away you go! Oh yeah, it's a scroll compressor too!

[condenseddave]

Originally posted by jerrycoolsaz


Guys everywhere feel the way you do until they get trained on how to do it right. Including myself.

Same here.

Freakin' guy doesn't even know the name of the gas he's using.

[condenseddave]

Originally posted by 2seasons-employed
youre too funny i had read more , dont attach your beliefs to the manufacturer's specifications, lmfao,Neither 404, nor 408, or even HP80 will cause compressor failure. All are approved by the major compressor manufacturers. "all except for hp-81 according to diamond dave and his personal friends at the manufacturing plants, also, dave it doesnt take much more than 13 lbs for a small to medium application depending on the location or length of the line-set, or size of compressor,etc;, also dave read your charts 404-a will phase out...... they all will just like you! yoou are just full of yourself dave and your impolite answer or attack is irresponsible, and shows yoour inexperience! you treat me so bad since the baby didnt come?

Well, cupcake, oh you of so much experience, how's about posting up a link that shows when 404A will be phased out?

The EPA tends to disagree.

You've been doing this HOW long?