Max distance for Split A/C units

[texanman]

What is a max rule of thumb for distance between the condensor and evaporator for typical small (around 10 ton) units on commercial retail buildings? Can refrigerant lines be oversized to reduce pressure drop? Is there a vertical distance rise/fall limit? Should the unit be ordered with any special options?
thanks,

 

[lowedogg]

100' line length is the rule of thumb, but the manufacturer should always be consulted.

 

[imok2]

If piping limitations are not available for the system, such as when you are moving an older machine, you can use a general rule of thumb. If the line set will not be more than 75 feet long, you are using the factory-recommended line size, and it’s not pushing liquid uphill more than 25 feet, very likely no special considerations are necessary. Remember, this is just a rule of thumb.

 

[Wareagl487]

For 5 ton and less, the majority of manufacturer's can run 250 equivalent feet (accounting for elbows and offsets)maximum. Most also warranty to 200 feet of lift with condensing unit above the air handle or 80 feet with the air handler above the condenser. We require in our specifications the manufacturer submit refrigerant pipe sizing calculations for long line applications. Over 5-ton you have some serious limitation 50 to 75 feet equivalent is about the maximum.

Attached is some helpful information provided by Carrier.

Andy W.

 

[trashcanman]

Some of the newer split systems like Daikin claim to go as far as 400' from the compressor.

 

[HVAC68]

The ones that Daikin claim that can go as far as 400', are the VRV systems (with inverter compressor technology) and not the conventional one-to-one split systems.

HVAC68