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height length line set

Hey guys without manufactures literature how do I figure correct subcooling for these jobs,?1/2 psi rule? Is that correct? And how how it's that rule applied or should I just add a Schrader tee with misg? Thanks Paul s
ASM Mechanical Company
Located in Staten Island NY
Servicing all 5 boroughs of NYC.
[email protected]


  • Techman
    Techman Member Posts: 2,144
    edited July 2014
    Height of lineset

    Height is one thing(1/2 psi),tubing length is another (upto 3psi), LLFD is another(1 psi),  elbows & fittings is still another( ???), LL Solenoid Valve is also figured (1psi). The pressure access fitting will give you what resistance you actually have. And the SGMI will let you see the SubCooling. PaulS w/ a picture of the T and SGMI, I will send you both. Don't forget the two press readings.
  • Spence
    Spence Member Posts: 316
    Sub Cooling

    In residential applications, until you can obtain the manufacturer's data, you most likely are safe with 10 degrees.