On Jun 14, 6:15 pm, Bill wrote:
We are replacing our 15 yr old 3 ton Trane 10 seer (still works but
not efficient and underpowered) with an American Std 3 1/2 ton heat
pump with variable speed air handler 14 seer. Air handler in the
garage, compressor outside in backyard about a 16 ft. straight line.
The copper used to run underground (straight line); a few years ago we
had a leak and before I had a chance to talk with the repair guys they
ran a 50 ft length around the garage, through the utility room then
out to the back. This has worked but I have always wondered about the
efficiency. Since we are going to the expense of repl the old unit I
am wondering if it would be worth it (does it even matter?) to run a
new line of a much shorter distance 18 - 25 ft depending if we go
underground or above. Does this create a higher load? Thanks - Bill

I think when you increase from 3 to 3.5 ton they will probably want to
replace the lineset. I think the 3.5 ton will require a 1 and 1/8th
inch suction line. And yes I would want a shorter more direct run....I
dont know if you would notice much in an efficiency increase but a
shorter more direct route leaves less joints in the
tubing...hopefully....

Also...a new lineset will leave less chance of leaving behind any
contamination from the old system if it wasnt as clean as dry as it
should be.