Connection Of Refrigerant Tubing - Trane MCC 518 ZB Installation Manual

Connecting the unit with flaring
procedure
1. Flaring (If piping is procured or cut
at the site). Cut the copper tube to
the required length with a tube
cutter. It is recommended to cut
approx. 30-50 cm. longer than the
tubing length you estimate.
2. Hold each pipe downward when
cutting and remove burrs at the
end of the copper tube with a tube
reamer or file. This process is
important and should be done
carefully to make a good flare
(Figure 9 and Figure 10).
Copper
tubing
Reamer
Figure 9
Deburring
Before
Figure 10
When reaming, hold the tube end
downward and be sure that no
copper scraps fall into the tube.
3. Remove the flare nut from the
unit and be sure to mount it on
the copper tube.
4. Make a flare at the end of copper
tube with a flare tool (Figure 11).
Flare nut
Copper
Flare tool
Figure 11
6

Connection of Refrigerant Tubing

and Condensate Drain Piping
A good flare should have the
following characteristics:
- Inside surface is glossy and
smooth.
- Edge is smooth.
- Tapered sides are of uniform length.
Bending
5. When bending the tube, be careful
not to crush it. To prevent crushing
of the tube, bend it gently and do
not bend the tube at a radius
curvature of less than 100 mm.
6. If the copper tube is bent or pulled
too often, it will become stiff. Do
not bend the pipe more than three
times at one place.
Cautions before Connecting
Tubes Tightly
7. Be sure to apply a sealing cap
or water-proof tape to prevent
dust or water from getting into
the tubes before they are used.
8. Be sure to apply refrigerant
lubricant to the matching surfaces
of the flare and union before
connecting them together. This
is effective for reducing gas leaks
(Figure 12).
After
Connection
9. For proper connection, align the
union tube and flare tube straight
with each other, then screw in the
flare nut lightly at first to obtain a
smooth match (Figure 13).
tubing
Union
Apply refrigerant
lubricant here
Figure 12
Flare nut
Figure 13
10. Tighten the flare nut to the
specified tightening torque with
torque wrench and adjustable
wrench.
Condensate Drain Piping
- The drain hose should run straight
down the wall to a level where the
runoff will not stain the wall.
- There should be no traps. Avoid
putting the end of the hose in
water.
- To conveniently drain the system,
the drain hose must slant
downward, with a slope of at least
1 : 50 to prevent leakage as shown
in figure 14.
Figure 14
- When the drain hose is placed in
the room, insulate the hose with
foam polyethylene to avoid
damage to the ceiling or furniture.
- After completing installation of
refrigerant lines, wiring and drain
connections, bind the tubing,
wiring and drain hose (check if
local codes permit binding) into a
bundle by using tape at 100 or
200 mm (4" to 8") intervals. Make
sure the drain hose is at the bottom
of the bundle (Figure 15).
Drain hose
Figure 15
MCC-SVN02A-EN