Help me identify this compressor

[SustaiN]

Today I got an old deepfreezer from the scrapyard. The stickers has been destroyed but there is still some marks from them and i'm almost sure it's a Danfoss. The refrigerant is R12 and the freezer seems to work perfect.

Here is a pic of it:
http://img412.imageshack.us/img412/4853/dsc017934vx.jpg (http://imageshack.us)

If you know anything about this compressor (ratings etc.) please let me know and do you think it would be enough for a decent single stage?
;)

[SustaiN]

Update. I took these pictures to help identifying the compressor:
http://img453.imageshack.us/img453/796/dsc017964gu.th.jpg (http://img453.imageshack.us/my.php?image=dsc017964gu.jpg)

http://img453.imageshack.us/img453/6766/dsc017979db.th.jpg (http://img453.imageshack.us/my.php?image=dsc017979db.jpg)

http://img453.imageshack.us/img453/1658/dsc017983kf.th.jpg (http://img453.imageshack.us/my.php?image=dsc017983kf.jpg)

Is it a 1/4 hp or higher. I really want to know if I can use this compressor for my comming ss project ;)

[Marvin]

I think would be hard to help if it doesnt have any label or reference....

[Stewie007]

Its got a stamp, I'd check that with the major manufacturer codes.

It looks like it might be a Tecumseh to me. But they all look pretty similar. So who knows..

[Gray Mole]

99% sure it's a danfoss, and from the size of it, I'd say FR7.5A or FR10A with optional oil cooler. My FR7.5A has almost the same code, and the '75A' in the upper code might mean 7.5 displacement.

If it's an FR7.5a, it's 1/5HP and I'd say it would work well in a single stage. I just built a chiller from mine and and it's working quite well.

Send an email to Danfoss, they'll be able to cross reference the compressor for you.


Gray

[SustaiN]

Yeah I was also almost sure it was a Danfoss. today I got some new compressors for free and they all work great. One of them is a "big" Aspera - a little bigger than the Danfoss you've just identified for me (thanks btw ;)). which one should I choose:

http://img500.imageshack.us/img500/1774/dsc018003zs.th.jpg (http://img500.imageshack.us/my.php?image=dsc018003zs.jpg)

http://img496.imageshack.us/img496/1213/dsc018015iv.th.jpg (http://img496.imageshack.us/my.php?image=dsc018015iv.jpg)

http://img496.imageshack.us/img496/6463/dsc018023qa.th.jpg (http://img496.imageshack.us/my.php?image=dsc018023qa.jpg)

http://img496.imageshack.us/img496/4095/dsc018032mi.th.jpg (http://img496.imageshack.us/my.php?image=dsc018032mi.jpg)

http://img496.imageshack.us/img496/1456/dsc018041qw.th.jpg (http://img496.imageshack.us/my.php?image=dsc018041qw.jpg)

http://img496.imageshack.us/img496/4650/dsc018052vs.th.jpg (http://img496.imageshack.us/my.php?image=dsc018052vs.jpg)

http://img496.imageshack.us/img496/2325/dsc018068rq.th.jpg (http://img496.imageshack.us/my.php?image=dsc018068rq.jpg)

... and NO I don't like scweppes Tonic water hehe :). It was just the only thing I could find so you could compare the compressors hight.

[Gray Mole]

Hey that TL2.5 is cute ;) I've got a TL4A and thought it was pretty small lol

The FR7.5 if that's it's size for sure is a good little compressor for single stage. At 1/5HP is ok, but not gonna set any temp records.

If you've got one that's a little bigger, you could use it, but the 2.5 is jsut a little small for cpu I think. Good GPU cooler though :D

What's the specs of 'em all?? You lucky :banana: lol Wish I could get more freebies!

Gray

[SustaiN]

hehe yeah I know its a little small. Ill probably use it for making a vacuum by connecting it in series to a couple of the other compressors :)
The problem is I don't have any specs, the labels have been taken off from the biggest compressors (the aspera and the danfoss FR7.5) :( The aspera compressor is physically bigger than the FR7.5 but I'm not sure its better though. If I search for the number printed on the top of it I don't get anything :(

[SustaiN]

Well I finally think I've found some specs for the aspera compressor. According to a french site I found out that the compressor is a Aspera LBP-LST 1/4 HP, 715.6 BTUH at 45 fahrenheit. Isn't this okay specs.?

[the_new_guy]

where do you get the freebee compressors?

[SustaiN]

A friend of my dad had some of these lying around and my dad then brought some home to me :)

[Gray Mole]

Sweet :) I've been lucky buying 'em for pretty cheap lately so I don't feel so bad.

It's a tough call on the compressors but I think the 1/4HP is the winner.

If it doesn't give what you want you can always chop it ou and pipe in the Danfoss, once the system's together it's pretty easy to swap compressors.

You shoudl be able to make some nice toys with those though, you could always try to cascade the 1/4 and 1/5HP compressors for a GPU hehehehe

Gray

[the_new_guy]

hey i noticed that the first compressor has a oil cooler, one of the compressors i was looking at to buy also has a oil cooler, can i just block them will they help or cause probs ? should i look for a compressor without a oil cooler?

[Gray Mole]

The compressor I used (FR10A) in the Low stage on my cascade is a version with oil cooler, and I just left the rubber blanks on it. I don't know if that's a problem, but it ran without a problem, and that part is isolated so I wasn't worried.

I have another compressor with oil cooler and it said in the specs of it that it was for R22 with air or oil cooling, and for R502 with air AND oil cooling, so I think it's just the amount of heat on the compressor, if it's going to get more abuse, you need to cool it more effectively.

Gray

[SustaiN]

Hehe yeah could be pretty cool making a cascade but I think I wouldn't get good results with these compressor. Another thing is that this is going to be my first build so jumping into cascades wouldn't be easy for me even though I might be using some "low pressure" gasses :)

Well, I think I'll use the Aspera compressor then. It's in better condition than the danfoss so I don't need to give it a new paintjob etc. But lets see, if it doesn't work i'll just swap the compressors.
I just have three question now: If I use the Aspera compressor, would it then be fine just to connect the last three compressors in series and make a good vacuum pump. If so in which order should I connect them? Finally, do I need to use nitrogen if I make a good vacuum?

Thanks for the quick answers and your help in this thread!!! :)

[the_new_guy]

how does the oil get circulated? maybe i will put a small radiator to cool the oil, and use a standard condenser and run 402a( if i find any, no luck yet) the compressor is a 134a 1/4 hp

sorry for hijacking thread.

[Gray Mole]

Nitrogen is a 'luxury' item, but it's very useful and I highly recommend it. It makes vaccing far more effective, and can cut vac times by a long ways. It's also very good for pressure testing.

It really depends on how deep a vac you can pull. Unless you have a micron/torr gauge I don't know if I'd recommend using 'series' compressors cos you won't know if you're pulling hard enough to get the moisture out.

I don't have a micron gauge yet, but I've got a pump that pulls to 15 micron and as long as I blast the system out I'm pretty sure it's clean. Still not 100% without a gauge but I just can't afford one atm.

You can try it out though, and if it takes all the moisture out, and you don't get moisture blockage in the captube then you're fine. Just easier if you can speed up vac's and know where you stand for vacuum pressures.

Sounds like you're on your way for phase though, just buy the tools as you can afford them, and you'll notice that you KNOW if you NEED something or you can live without it as you go along, believe me lol

Gray

[SustaiN]

The_new_guy no that's a good question you're not hijacking anything :) I'm not quite sure how it works but I don't think you need an oil cooler ;)
Well, I've just ordered alot of the needed tools to make a unit. This is what I'll get:
Manifold guage with hoses
flaring tool
swaging tool
pipe bender
pipe cutter

Hope this is enough for making the first unit. After I have made this I think I'll get the more proffesional tools such as a real vacuum pump gradually ;)

Btw. can't I read how deep the vacuum is on the manifold? :)

[Gray Mole]

hehe

I thought I'd be fine with the manifold, but it's only a guideline. A micron gauge tells you DEEP vacuum accurately, so you know for sure if you're losing pressure ie leaktests, or if you've pulled deep enough to get the moisture out completely.

I plan to get one as soon as I've got the cash, but you're right, the tools sure add up.

I didn't run an oil cooler at all on the cascaded one and it's fine.

I actually ran the other with the suction line through it and it was a pain to pipe in, and it still ran quite hot, so I don't know. I'm pretty sure you're supposed to run an oil pump line through it with a radiator, but I've never bothered.

Gray

[SustaiN]

Okay thanks! :) I'll probably get a micron guage later. I think I've spend enough money on tools for now!! hehe
When I do the evac I think I will heat up the pipes with my propane torch to speed up the evac and to to be (almost) sure all the moisture has boiled off. ;)

[wdrzal]

Nitrogen is a 'luxury' item,

Gray
Nitrogen is not a luxury item,its mandatory. the main reason for nitrogen is to prevent oxidation and scale from forming on the inside of the copper when brazing. This scale will block filters and valves and cap tubing and will cause compressor oil to turn rancid. Once this forms on the inside it is impossible to remove completly .

a micron gauge can wait, nitrogen setup can't

[chilly1]

A 1/5 hp compressor is goofd for a single stage and will do -38 to -45 loaded depending on load and charge.

[Gray Mole]

Nitrogen is not a luxury item,its mandatory. the main reason for nitrogen is to prevent oxidation and scale from forming on the inside of the copper when brazing. This scale will block filters and valves and cap tubing and will cause compressor oil to turn rancid. Once this forms on the inside it is impossible to remove completly .

a micron gauge can wait, nitrogen setup can't

I've been purging out with propane lately as I'm finding it's doing a better job and is cheaper for me to use. I don't recommend that to anyone as there can be dangers but that's what I'm using more now than ever. I'm also qualified to weld through the automotive trade, and have taken relevant courses in Propane handling.

Nitrogen is not necessary for purging if you have other means. Nitrogen is not necessary for vacuuming, though it's very helpful. I still blast out with nitrogen now that I'm set up for it, but for brazing I really like propane.

To me, Nitrogen is a luxury item. A purging gas is mandatory.

I wasn't looking for an argument Walt.

Gray

[SustaiN]

Thanks for a great thread. This sorted a lot of things out for me!! love this forum ;)

[SustaiN]

Btw, one last question. Which refrigerant should I choose. I think I can get R404a easily but would that work well out with this compressor you think (I know I have to change the oil to POE)? Or what else would work well?

[the_new_guy]

use R402a/R507/R404a
R402a>R507>R404a