Piping Connections; Precautions During Line Installation - York STEALTH H4TS024 Installation Instruction

035-14511-001 Rev. A (0602)
Dry nitrogen should always be supplied through the
tubing while it is being brazed, because the tempera-
ture required is high enough to cause oxidation of the
copper unless an inert atmosphere is provided. The
flow of dry nitrogen should continue until the joint has
cooled. Always use a pressure regulator and safety
valve to insure that only low pressure dry nitrogen is
introduced into the tubing. Only a small flow is nec-
essary to displace air and prevent oxidation.
All connections to be brazed are copper-to-copper and
should be brazed with a phosphorous-copper alloy material
such as Silfos-5 or equivalent. DO NOT use soft solder.
Install the TXV bulb to the vapor line near the equalizer line,
using the two bulb clamps furnished with the TXV assembly.
Ensure the bulb is making maximum contact. Refer to TXV
installation instruction for view of bulb location.
In all cases, mount the TXV bulb after vapor line is
brazed and has had sufficient time to cool.
8. Bulb should be installed on a horizontal run of the vapor
line if possible. On lines under 7/8" OD the bulb may be
installed on top of the line. With 7/8" OD and over, the
bulb should be installed at the position of about 4 or 8
o'clock.
9. If bulb installation is made on a vertical run, the bulb
should be located at least 16 inches from any bend, and
on the tubing sides opposite the plane of the bend. On
vertical bulb installations, the bulb should be positioned
with the bulb tail at the top, so that the bulb acts as a res-
ervoir.
10. Bulb should be insulated using thermal insulation pro-
vided to protect it from the effect of the surrounding
ambient temperature.

PIPING CONNECTIONS

The outdoor condensing unit may be connected to the indoor
evaporator coil using field supplied refrigerant grade copper
tubing that is internally clean and dry. Units should be
installed only with the tubing sizes for approved system com-
binations as specified in Tabular Data Sheet. The charge
given is applicable for total tubing lengths up to 15 feet. See
Application Data Form 690.01-AD1V for installing tubing of
longer lengths and elevation differences.
NOTE:
Using a larger than specified line size could result in
oil return problems. Using a line size smaller than specified
will result in loss of capacity and other problems caused by
insufficient refrigerant flow. Slope horizontal vapor lines at
least 1" every 20 feet toward the outdoor unit to facilitate
proper oil return.
4

PRECAUTIONS DURING LINE INSTALLATION

1. Install the lines with as few bends as possible. Care must
be taken not to damage the couplings or kink the tubing.
Use clean, hard drawn copper tubing where no apprecia-
ble amount of bending around obstruction is necessary.
If soft copper must be used, care must be taken to avoid
sharp bends which may cause a restriction.
2. The lines should be installed so that they will not obstruct
service access to the coil, air handling system or filter.
3. Care must also be taken to isolate the refrigerant lines to
minimize noise transmission from the equipment to the
structure.
4. The vapor line must be insulated with a minimum of 1/2"
foam rubber insulation (Arm-A-Flex or equivalent). Liquid
lines that will be exposed to direct sunlight and/or high
temperatures must also be insulated.
Tape and suspend the refrigerant lines as shown. DO NOT
allow metal-to metal contact. See Figure 3.
5. Use PVC piping as a conduit for all underground installa-
tions as shown in Figure 4. Buried lines should be kept
as short as possible to minimize the build up of liquid
refrigerant in the vapor line during long periods of shut-
down.
Sheet Metal Hanger
Liquid
Line
Incorrect
Correct
FIGURE 3 : Insulation of Vapor Line
TO INDOOR COIL
LIQUID LINE
PVC
CONDUIT
FIGURE 4 : Underground Installation
6. Pack fiberglass insulation and a sealing material such as
permagum, around refrigerant lines where they pene-
trate a wall to reduce vibration and to retain some flexibil-
ity.
7. See Form 690.01-AD1V for additional piping information.
Tape
Insulated Vapor Line
TO OUTDOOR UNIT
INSULATED
CAP
VAPOR LINE
Unitary Products Group