# 48478A006
Page 9
removed during the first flush.
After each system
flush, allow the recovery machine to pull a vacuum
on the system at the end of the procedure.
9. Close the valve on the inverted R22 cylinder and the
gauge set valves. Pump the remaining refrigerant out
of the recovery machine and turn the machine off.
10. Use nitrogen to break the vacuum on the refrigerant lines
and indoor coil before removing the recovery machine,
gauges, and R22 refrigerant drum. Re-install pressure tap
valve cores into the 4SHP16LT unit’s service valves.
11.
Install a thermal expansion valve approved for use with
R410A refrigerant
in the liquid line at the indoor coil.
Refrigerant Metering Device
4SHP16LT units are designed for use with TXV systems
only. An R410A system will not operate properly with an
R22 metering device.
Expansion valves equipped with Chatleff-type fittings are
available from the manufacturer. See Table 3 for proper
TXV for each unit.
To install an expansion valve (see Figure 9):
1. Separate the distributor assembly and remove the
piston orifice and used teflon seal. Insert nozzle end of
the expansion valve along with a new teflon seal into the
distributor and tighten to 20 – 30 ft. lbs. Use backup
wrench on all wrench flats.
Overtightening will crush
the teflon seal and may cause a leak.
2. Attach liquid line portion of distributor assembly along
with new teflon seal to the inlet of the expansion
valve. Tighten to 20 – 30 ft. lbs. Use backup wrench
on all wrench flats.
Overtightening will crush the
teflon seal and may cause a leak.
3. Connect the external equalizer line to the equalizer
port on the suction line and tighten to 8 ft. lbs.
Table 3
TXV Data
l
e
d
o
M
t
r
a
P
r
e
b
m
u
N
0
3
-
,
4
2
-
T
L
6
1
P
H
S
4
1
0
V
X
T
4
H
6
3
-
T
L
6
1
P
H
S
4
2
0
V
X
T
4
H
-
T
L
6
1
P
H
S
4
0
6
-
,
8
4
3
0
V
X
T
4
H
4. Strap the superheat sensing bulb to the suction header.
If installing an expansion valve on an indoor coil that
previously used a fixed orifice, be sure to remove the
existing fixed orifice. Failure to remove a fixed orifice
when installing an expansion valve to the indoor coil will
result in improper operation and damage to the system.
Manifold Gauge Set
Manifold gauge sets used with systems charged with
R410A refrigerant must be capable of handling the higher
system operating pressures. The gauges should be rated
for use with pressures 0 – 800 on the high side and a low
side of 30" vacuum to 250 psi with dampened speed to
500 psi. Gauge hoses must be rated for use at up to 800
psi of pressure with a 4000 psi burst rating.
Liquid and Suction Line Service Valves
The liquid line and suction line service valves (see Figure
10 on page 10) and service ports are used for leak testing,
evacuating, charging, and checking charge.
Each valve is equipped with a service port which has a
factory-installed Schrader valve. A service port cap
protects the Schrader valve from contamination and
serves as the primary leak seal.
To Access the Schrader Port:
1. Remove the service port cap with an adjustable wrench.
2. Connect gauge to the service port.
3. When testing is completed, replace service port cap.
Tighten finger tight, then an additional 1/6 turn.
If necessary, remove R22 flow control device
(fixed orifice/thermal expansion valve) from
existing line set before installing R410A approved
orifice or expansion valve.
Metering Device Installation
Figure 9
