Page 27
mrcool.com
Refrigerant Piping Connection
3.
TORQUE REQUIREMENTS
4.
1. Excessive torque can break the nut or damage the refrigerant piping. You must not exceed the
torque requirements shown in the table below.
2. You can find the coupling size and torque rating by looking for the stamped part number on the
connector and using it to find the corresponding torque rating in the table below.
3. Note there may be differences in TorqueWrenches (i.e. automotive torque wrench versus an
HVAC torque wrench) and that a socket-style wrench cannot be used here.
NOTE: Torque ratings in the table below are to be used if you have access to an HVAC torque
wrench. These are available for purchase from online retailers. However, it is possible to complete
installation of refrigerant line sets with conventional open-ended/crescent wrenches. It is
imperative, however, that you not overtighten the connector, and that once the lines have been
fully connected, you follow the steps to check for leaks. If you do not feel comfortable attempting
this, please contact a qualified HVAC technician.
1
2
FA06
FA09
FA12
FA16
3/8 in (9.5 mm)
1/2 in (12.7 mm)
3/4 in (19.1 mm)
1 in (25.4 mm)
18-20 lb/ft
(24.4-27.1 Nm)
30-35 lb/ft
(40.6-47.4 Nm)
45-50 lb/ft
(61.0-67.7 Nm)
60-65 lb/ft
(81.3-88.1 Nm)
Stamp
(on
connector)
Coupling Size
inch (millimeter)
Maximum
Tightening Torque
lb-ft (N-m)
Using the image below as a guide, and the steps
outlined in this paragraph, you will now tighten the
nuts of the screw connectors of the Fast Connect™
Line Set to the indoor unit. Using two appropriate
sized open-ended wrenches (depending on the
dimensions of the connector) or adjustable crescent
wrenches, place one of the wrenches on the nut
marked “1”, and the other wrench on the nut marked
“2”, as shown in the image below. Now, turn the
wrench marked “2” in the direction of the rotational
arrows, as shown, while holding the other wrench in
place. Continue to tighten the connector until snug.
NOTE: work quickly and make sure the screw
connectors do not become crooked as you
tighten them.
*If an HVAC torque wrench is available:
Once the
connector is snug, using the torque wrench, tighten
the connector to the specified torque rating, listed in
the table above (based on pipe size).
*If an HVAC torque wrench is NOT available:
Using the two wrenches you used to tighten the
connector, once the connector is snug, turn the
wrench slightly beyond that point to torque the
connector, but do not overtighten it.
Repeat the same process for the second line.
