LAYOUT BEST PRACTICES
General Information / Guidelines
Refrigerant Piping System Insulation
All refrigerant piping from the outdoor unit to the indoor units must be insulated correctly for safety and usage. Y-branch connections, header
branch connections, refrigerant piping, field-provided isolation ball valves (if present), service valves, and elbows must be properly and
completely insulated using closed cell pipe insulation (up to the indoor unit piping connections). To prevent heat loss / heat gain through
the refrigerant piping, all refrigerant piping including liquid lines and vapor lines shall be insulated separately. Insulation shall be a minimum
requirements for Ethylene Propylene Diene Methylene (EPDM) insulation.
Inside the outdoor unit, maximum pipe temperature is 248°F and minimum pipe temperature is -40°F. For field insulation of refrigerant piping
between outdoor units and indoor units, consider the following pipe temperature ranges for an operating heat pump system:
• Heating mode refrigerant temperature ranges:
Liquid 75-118°F; High Pressure Vapor 95-220°F
• Cooling mode refrigerant temperature ranges:
Liquid 75-118°F; Low Pressure Vapor
All insulation joints shall be glued with no air gaps. Insulation material shall fit snugly against the refrigeration pipe with no air space between
it and the pipe. Insulation passing through pipe hangers, inside conduit, and/or sleeves must not be compressed. Protect insulation inside
hangers and supports with a second layer. All pipe insulation exposed to the sun and outdoor elements shall be properly protected with PVC,
aluminum vapor barrier, or alternatively placed in a weather-resistant enclosure such as a pipe rack with a top cover; and meet local codes.
thickness, and meet UL94 MF-1 flammability.
The design engineer should perform calculations to determine if the factory-supplied insulation jackets are sufficient to meet local codes and
avoid sweating. Add additional insulation if necessary. Check the fit of the insulation jacket after the header fitting and all run-out pipes are
installed. Mark all pipes at the point where the insulation jacket ends. Remove the jacket. Install field provided insulation on the run-out and
main trunk pipes first. Install the LG-provided insulation plugs on the ends of all unused header ports. Peel the adhesive glue protector slip
from the insulation jacket and install the clam-shell jacket over the fitting.