HVAC Question

What is in the pipes, its temperature, flowrate and pressure?

I know this may be radical thinking, but what does the maker of the equipment have to say about this?

If you fry a unit due to improper installation the manufacturer will not be obligated to replace it at a discount.

ASK THE MANUFACTURER.

As ignator and lyn have stated, follow the manufacturer's recommendation. Here's a link to Goodman's document, http://securenet.goodmanmfg.com/Toolkit/LongsetGuideLines/R-410A%20Long%20Line-set%20Application%20for%20Goodman%20Condenser%20Application.pdf, but you should follow your specific manufacturer's advice. They may also have additional requirements such as crankcase heater, hard start assist, TXV, oil trap, etc. You can also Google 'long line set'.

The 3/4" and 3/8" are fine for that run, no need to alter line size...I've run them much further with no problems...Some manufacturers may recommend different sizes for different models, just use the recommended size for the model unit you are installing for the entire run.....More important to check for leaks, get a good vacuum, don't kink the line, and install a filter drier....

The 3/8" line, probably tube rather than pipe, is liquid refrigerant, not discharge. There is no such thing as 7/8" pipe; that is probably tube O.D. Because the evaporators are below the rooftop condensing units, oil return is a possible issue; if so, enlarged suction lines are undesirable. An enlarged suction line does not serve well as a suction accumulator. What is the refrigerant?

There is such a thing as 7/8ths pipe. ACR(air conditioning and refrigeration) pipe is rigid nitrogen charged (for moisture and dirt) with both ends stoppered. It comes in dimensions from 3/8th up to 4 1/8th. It drives plumbers nuts when I try to explain it to them. 3/4" copper plumbing pipe is the same OD as 7/8ths" ACR.

He should go with the manufactures specs and install "P" traps on every 10' of vertical riser.

That's not pipe; it's tube.

But in the trade warehouse's it is refereed to as pipe, Copper pipe / ACR. When you ask for tube they will ask you back......... do you need soft copper or Vinyl.

Basically, in the warehouses tube comes in a roll (annealed) and pipe is a stick (rigid dehydrated or open) in 20' lengths.

Right or wrong terminology is different here than in the field, always has been, ahhh well, time for a beer.

Beer is universal

You might compare what happens when Googling "ACR pipe" versus "ACR tube". Many of the "pipe" hits lead to "tube". There are many more hits on "tube" than "pipe", and relatively fewer of them mention "pipe".

Pipe is traditionally specified by nominal I.D.; tube by actual O.D.

I was a union refrigeration fitter for some years, and a system designer/drafter even longer. For most of this time, supply houses in the U.S. referred to copper water pipe (e.g., 3/8, 1/2, 3/4; actually 1/2, 5/8, 7/8 O.D.) and to ACR tube. Sizing tables were based on tube sizes. It is possible that the distinction and language have degenerated recently. Thank you so much for helping.

If you have no experience and support from manufacturer - don't do it, a lot of consultant, engineers, technicians had carried out with negative result and they damage the compressors.

You might loss your job - if you do ti?

Your equipment should come with directions for pipe size increase/reduction. 10 M rise will require careful consideration for proper oil return, as another poster has said. This much rise will almost certainly require traps, too. To keep from voiding warranty, get the info from the manufacturer. This situation is beyond the area where rules of thumb can be good enough. Remember, good enough is not always right but right is always good enough. -- JHF

For strters we need to know which refrigerant you will be using. That, as well as the capacity and length of run, effects the sizing of th pipe.

Lou Bindner

R410 is the refrigerant for these machineas.