copper oil supply line

ewh

Sometimes it seems like the simplest questions are the hardest to find answers to with web searches....

what kind of copper tubing should be used for a 3/8 od oil supply line? 3/8 refrigeration, 1/4 type L, utility grade?
(assuming it isn't touching concrete, buried, etc.)

thanks.

bulldoglax

3/8 soft copper polyethylene coated

ewh

does it have to be polyethylene coated if it is up off the ground?

also, i have seen it buried in a corrugated blue plastic tube. does that meet code? and if so what grade copper should be used in that tube?

Bob Bona_4

I'd run 3/8" *ID*. Either one is soft L rolled. Sleeved or coated meets code, you're protecting from corrosion, and where it is in a traffic area it should be damage protected.

ewh

okay, so type L soft copper is the stuff to use...
just out of curiosity, why do you suggest 3/8 id?

Bob Bona_4

Why not go the bigger size if you're going to do it. Gives more wiggle room for sludge accumulation, and reduces friction loss if it's any kind of a lift situation.

STEVEusaPA

I'd only go bigger if it's recommended by the pump manufacturer for proper sizing. Bigger can make more it harder to eliminate air, especially if it's not a gravity job.

Jim Hankinson

Check with your local code official if this is something that will be inspected. Some jurisdictions require minimum 1/2" OD. As Steve said it can be harder to get all the air out, especially if the line goes overhead.

EBEBRATT-Ed

If tubing is bought at a refrigeration supply house it will be sold as OD outside diameter size. So 3/8" od (refrigeration tubing marked ACR) is exactly the same as 1/4" L (nominal size tubing) except the nominal size plumbing tubing is not sealed and cleaned for refrigeration use. Neither one is coated for installing in concrete floors or buried.

You just need to look at the box the tubing is in . It is usually marked.
same goes for:
1/2" od=3/8" nominal
5/8 od= 1/2" nominal
3/4 od is an oddball used on refrigeration only
7/8" od=3/4 nominal
1 1/8" od= 1" nominal
etc all the way up to 4 1/8 od=4" nominal

ACR=air conditioning and refrigeration tubing is the same as "L" tubing except that it has been cleaned and dehydrated

ewh

thanks for all the replies.

ebabratt-ed: that is exactly what i wanted to know. and probably why it was hard to find an answer about whether to use refrigeration or type l.

hatterasguy - I did look at the price!

Solid_Fuel_Man

If any physical protection is needed, I use 3/4" SCH80 electrical pvc conduit. I've had good luck pushing 3/8 ref tubing through the factory 90's of the pvc as well.