Installation Guide for NHPA Split-System Heat Pumps
6
20’
Max*
Vertical
Change
Standard
Line Set
50’ Max*
Line Length
20’
Max*
Vertical
Change
*Call National Comfort Products
for Greater Line Lenghts
For example:
• When the refrigerant lines have to be fastened to floor joists or
other framing in a structure, use isolation type hangers.
• Isolation hangers should also be used when refrigerant lines
are run in stud spaces or enclosed ceilings.
• Where the refrigerant lines run through a wall or sill, they
should be insulated and isolated.
• Isolate lines from all ductwork.
• Minimize the number of 90� turns.
Maximum Allowable Liquid Line Pressure Drop =
50 PSI
Subtract .43 PSI for each foot of Liquid Lift (if any)
Do Not Exceed this value when selecting Liquid Line
Field Installation:
Install the units per the manufacturer’s recommendations. Route
the copper lines between the unit
Step 1:
The tubing should be cut square. Make sure it is
round and free of burrs at the connecting ends.
Clean the tubing to prevent contaminants from
entering the system.
Step 2:
Wrap a wet rag around the copper stub before
brazing
.
Note: Take precautions to prevent noise
within the building structure due to
vibration transmission from the refrigerant
lines (Some examples provided below).
