Believe it or not Trane Application Guide SS-APG001-EN says "to slope 1/4" to 1" per 10 feet of run toward the evaporator"
We were installing some 80 ton splits about 15 years ago when i got this. I took issue with it and called engineering, they said yep if you install our equipment that is the way we want it done.
There is a lot of other good stuff in there too, about P traps and such.
Remember this is for their system
Slope in pipes towards compressor is so important for oil return. I had an opportunity to repipe a 10,000 sq ft freezer that was not properly sloped. Before the job we constantly had oil problems and endless compressor failures. Afterwards never lost one compressor! It was an older system using Carlyle 5F40 compressors. It took some time to convince the customer it was a major issue with his system. Now he is my best customer and sends me tons of referrals.
C:\Users\morsi_000\AppData\Local\Packages\microsof t.windowscommunicationsapps_8wekyb3d8bbwe\LocalSta te\LiveComm\b041c7cb911ec3cd\120712-0049\Att\20003a0f\WP_20140329_003.jpg
How does this one grad everyone?..... got a call for a burned up Copeland compressor. At least a full bubble off from the unit towards the riser. Lasted less than 1 year
That's a really neat pipe support and condenser mounts. Never understood how someone could install a 2500 dollar condenser and not read the manual? The heatcraft manual is awesome and shows how to install with drawings even. I bet there is no p trap at the evap either? Could have brought the lines up 2 feet higher and they would have sloped to compressor. That would require about 10 more scrap block supports though......
actually is a P trap down below.....I bet its filled with 46oz of oil though. I should have taken pictures of the other 3 units piping. One is about a chest high loop that has no support, 30 ft horizontal run just poked into the side of the condensing unit.
What is wrong with this piping? I don't see anything that would cause any oil return issues with that tiny little system.
Double suction risers with single circuit compressor unloaders would require inverted trap. Would also require other pipe sizing requirements also.