7). Mount the valve stems nuts and the service
port cap.
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N·m (13.27 ft·lbs).
Always leak check after servicing the refrigerant
system.
3. Adding refrigerant if the pipe length
exceeds chargeless pipe length
Procedure:
1) Connect the low pressure gauge from the
gauge manifold set to the 3 way service valve
(this is the blue hose on most sets).
2) Connect the middle hose from the manifold set
to the refrigerant container (this is the yellow line
on most sets). With refrigerant 410A the container
must be inverted (upside down) when adding the
refrigerant. Note that the 2 way and 3 way valves
must be in the open position.
3) The air in the gauge hoses needs to be purged
out. use the pressure from the system to purge
the low side line, loosen the connection on the
manifold for a second, next open the to valve on
the refrigerant container to pressurize the line,
now loosen that hose at the manifold for a second
and purge that line.
4) Set the refrigerant container on an electronic
charging scale and record the weight or zero the
scale depending on the scale used. Next
determine the refrigerant charge to be added.
5) Start the unit in the cooling mode and lower
the set point so the unit won’t shut off during the
charging procedure.
6) Refrigerant can now be added to the system,
open the low pressure valve on the gauge
manifold set to start charging the unit with liquid
refrigerant, keep track of the refrigerant being
added to the system (do not overcharge the
system).
7) Once the correct charge has been added to
the system close the low pressure valve on the
gauge manifold set and record the operating
pressure. The system is now charged and the
unit can be shut off. Close the valve on the
refrigerant container and disconnect the hose
from the manifold set, also disconnect the hose
from the 3 way valve and replace and torque all
caps.
Be sure to use a torque wrench to tighten the
service port cap to a torque 18N·m (13.27 ft·lbs).
Always leak check after servicing the refrigerant
system.
5.5 Adding the refrigerant after running
the system for many years
Procedure
1) Connect the low pressure gauge from the
gauge manifold set to the 3 way service valve
(this is the blue hose on most sets).
2) Connect the middle hose from the manifold set
to the refrigerant container (this is the yellow line
on most sets). With refrigerant 410A the container
must be inverted (upside down) when adding the
refrigerant. Note that the 2 way and 3 way valves
must be in the open position.
3) The air in the gauge hoses needs to be purged
out. use the pressure from the system to purge
the low side line, loosen the connection on the
manifold for a second, next open the to valve on
the refrigerant container to pressurize the line,
now loosen that hose at the manifold for a second
and purge that line.
4) Set the refrigerant container on an electronic
charging scale and record the weight or zero the
scale depending on the scale used. Next
determine the refrigerant charge to be added.
5) Start the unit in the cooling mode and lower
the set point so the unit won’t shut off during the
charging procedure.
6) Refrigerant can now be added to the system,
open the low pressure valve on the gauge