Leak Testing - Lennox 12HPB Series Installation Instructions Manual

Service Valve
(Valve Closed)
service
port
to outdoor coil
service
port cap
Schrader valve open
to line set when valve is
closed (front seated)
Service Valve
(Valve Open)
insert hex
wrench here
service
port
to outdoor coil
service port
cap
Schrader
valve
Figure 13
Ball Valve (Valve Open)
Use Adjustable Wrench
To open: rotate Stem Counter-clockwise 90°.
To close: rotate Stem Clockwise 90°.
to outdoor coil
service port
cap
Figure 14

Leak Testing

After the line set has been connected to the indoor and
outdoor units, check the line set connections and indoor
unit for leaks.
stem cap
insert hex
wrench here
to indoor coil
(valve front seated)
stem cap
to indoor coil
stem cap
stem
ball
(shown open)
to indoor coil
service port
Schrader valve
Danger of fire. Bleeding the refrigerant
charge from only the high side may re-
sult in the low side shell and suction
tubing being pressurized. Appplication
of a brazing torch while pressurized
may result in ignition of the refrigerant
and oil mixture − check the high and low
pressures before unbrazing.
Refrigerant can be harmful if it is inhaled. Refrigerant
must be used and recovered responsibly.
Failure to follow this warning may result in personal
injury or death.
Danger of explosion: Can cause equip-
ment damage, injury or death. Never
use oxygen to pressurize a refrigera-
tion or air conditioning system. Oxygen
will explode on contact with oil and
could cause personal injury.
Danger of explosion: Can cause equipment damage,
injury or death. When using a high pressure gas
such as dry nitrogen to pressurize a refrigeration or
air conditioning system, use a regulator that can
control the pressure down to 1 or 2 psig (6.9 to 13.8
kPa).
Using an Electronic Leak Detector or Halide
1 − Connect a cylinder of HCFC-22 to the center port of the
manifold gauge set.
2 − With both manifold valves closed, open the valve on
the HCFC-22 cylinder (vapor only).
3 − Open the high pressure side of the manifold to allow
the HCFC-22 into the line set and indoor unit. Weigh in
a trace amount of HCFC-22. [A trace amount is a maxi-
mum of 2 ounces (57 g) or 3 pounds (31 kPa) pres-
sure.] Close the valve on the HCFC-22 cylinder and the
valve on the high pressure side of the manifold gauge
set. Disconnect the HCFC-22 cylinder.
4 − Connect a cylinder of nitrogen with a pressure regulat-
ing valve to the center port of the manifold gauge set.
5 − Connect the manifold gauge set high pressure hose to
the vapor valve service port. (Normally, the high pres-
sure hose is connected to the liquid line port; however,
connecting it to the vapor port better protects the man-
ifold gauge set from high pressure damage.)
6 − Adjust the nitrogen pressure to 150 psig (1034 kPa).
Open the valve on the high side of the manifold gauge
set which will pressurize line set and indoor unit.
Page 12
WARNING
WARNING
WARNING
WARNING