r-12 to 134 comp

[cube]

Has any changed to 134 comp and left the r-12 cap tube in on med temp unit?I so how did it work?

Thanks

[markettech]

Huh?????:confused: :confused: :confused:

[cube]

Huh?????:confused: :confused: :confused:

switching a r-12 unit to 134 but not changing the cap tube.

[markettech]

Why would you?

[k-fridge]

It's so close it should be fine as long as the compressor capacity is the same. But as asked above...why would you? Changing to 134 and POE you also need to blow the system out good and possibly flush to get the old oil out. You may find you have less capacity with 134 in an R-12 system.

I'd just charge it up with MP-39 or R-409, either will work great for Med temp. And you don't need a 134 compressor, just go back with an R-12 compressor. AB oil is best but on a close coupled system you're OK with mineral also.

[cube]

Why would you?

More and more supply houses are getting away from r-12 AE 4440 here.

[k-fridge]

More and more supply houses are getting away from r-12 AE 4440 here.

That's odd, very common compressor. Copeland has a twin for it too that is nearly identical. AEA 4440 comes with AB oil, great candidate for one of the blends.

[markettech]

K:

Good reply and I wasn't trying to be a smart a$$........Just get a little leery when a first timer comes on here and asks very very vague questions. Coupled with the fact that the poster has NO information in the personal profile, I sometimes wonder if its legit or maybe somebody's customer got PO'd cause a tech changed the cap tube and is now looking for ammunition.

[markettech]

Cube:

Give us some background. Have you converted a unit and it didn't work correctly?

[k-fridge]

K:

Good reply and I wasn't trying to be a smart a$$........Just get a little leery when a first timer comes on here and asks very very vague questions. Coupled with the fact that the poster has NO information in the personal profile, I sometimes wonder if its legit or maybe somebody's customer got PO'd cause a tech changed the cap tube and is now looking for ammunition.
Good point, I forget about the DIYers that come on here.

[cube]

Thank's guys.Relax live in FL been doing this 25yr's,no bar,or rest owner.Always use 409,so i was just asking.

[k-fridge]

Thank's guys.Relax live in FL been doing this 25yr's,no bar,or rest owner.Always use 409,so i was just asking.

Personally; I;m not a fan of 134, especially in retrofits. OK, I'll just blurt it out, IT SUCKS. LOL.

I'd stick with the AEA 4440 (Tecumseh 1/3 hp med/high temp R-12 or blends) and 409 any day.

[markettech]

Good enough Cube.....................welcome aboard.

Get you're post count up and apply for Professional status;)

25 years - maybe I can learn something from you:)

[cube]

Good enough Cube.....................welcome aboard.

Get you're post count up and apply for Professional status;)

25 years - maybe I can learn something from you:)

Thanks for the kind words.:)
Supply houses are more geared up for A/C down here.:(

[phosgene]

I have done it on small fractional horsepower systems and it has worked fine.

[the mojo]

Welcome to H talk cube. Come back often so we can shoot the breeze .:D

[icemeister]

While most of the R12 MT compressor changeouts and refrigerant retrofits I've done over the past ten years or so have been to interim blends such as R401A (MP39), more recently I have been swinging over to using R134A with good success.

The proper sizing of cap tubes is a good question. I use three different references as guides for selection.....Supco, JB Industries and Tecumseh. The Tecumseh chart essentially says to use the same size (ID) and length for either R12 or R134A while the others indicate a longer tube of the same ID is required. JB states add 10% and the Supco chart for a 1/3 HP MT on R12 is 72" of BC2 (.040") and 79" of BC2 for R134A which is also +10%.

In practice, I have used the original R12 cap tube size for R134A with no problems. Just be sure to adjust your charge to get between 20F and 40F superheat at the compressor with the box at temperature and you'll be good to go.

Also, stay away from those bullet type filter-driers. Use a Sporlan C032-CAP-T instead. ;)

[cyro]

I much prefer 134 over 409, Glide is better also.

Just put a 4440yxa and be done with it.

Most of todays smaller condenser fins are so close they tend to catch all the dust and clog faster which will raise your head, 409 and close fins just don't mix well.

[emcoasthvacr]

what would be the superheat for both LT & HT apps? I'm quessing 10-20 for LT, but what about HT?


While most of the R12 MT compressor changeouts and refrigerant retrofits I've done over the past ten years or so have been to interim blends such as R401A (MP39), more recently I have been swinging over to using R134A with good success.

The proper sizing of cap tubes is a good question. I use three different references as guides for selection.....Supco, JB Industries and Tecumseh. The Tecumseh chart essentially says to use the same size (ID) and length for either R12 or R134A while the others indicate a longer tube of the same ID is required. JB states add 10% and the Supco chart for a 1/3 HP MT on R12 is 72" of BC2 (.040") and 79" of BC2 for R134A which is also +10%.

In practice, I have used the original R12 cap tube size for R134A with no problems. Just be sure to adjust your charge to get between 20F and 40F superheat at the compressor with the box at temperature and you'll be good to go.

Also, stay away from those bullet type filter-driers. Use a Sporlan C032-CAP-T instead. ;)

[cube]

While most of the R12 MT compressor changeouts and refrigerant retrofits I've done over the past ten years or so have been to interim blends such as R401A (MP39), more recently I have been swinging over to using R134A with good success.

The proper sizing of cap tubes is a good question. I use three different references as guides for selection.....Supco, JB Industries and Tecumseh. The Tecumseh chart essentially says to use the same size (ID) and length for either R12 or R134A while the others indicate a longer tube of the same ID is required. JB states add 10% and the Supco chart for a 1/3 HP MT on R12 is 72" of BC2 (.040") and 79" of BC2 for R134A which is also +10%.

In practice, I have used the original R12 cap tube size for R134A with no problems. Just be sure to adjust your charge to get between 20F and 40F superheat at the compressor with the box at temperature and you'll be good to go.

Also, stay away from those bullet type filter-driers. Use a Sporlan C032-CAP-T instead. ;)

Never tried...but always wondered....COOL HAND LUKE.

[TGoodrich]

A Copeland ARE37C3IAA 1/3 HP compressor with R-414B (HotShot) works just fine. Icemeister is right on the mark recommending an 032CAP-T filter drier. An obstructed cap tube is often the cause of the compressor failure in the first place and POE oil only makes it more likely to plug!

[gerryboy00]

Also, stay away from those bullet type filter-driers. Use a Sporlan C032-CAP-T instead. ;)

never seen those. Is the T mean tap for press. reading on the dryer?

[markettech]

never seen those. Is the T mean tap for press. reading on the dryer?


You got it;)

[gerryboy00]

look what I just found :)

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lots of stuff in there:

http://www.uri.com/is-bin/intershop.static/WFS/PrcTransaction/-/en_US/docs/catalog03.pdf



.