OPEN VALVE STEMS GENTLY
When opening valve stems, turn the hexagonal
wrench until it hits against the stopper. Do not
try to force the valve to open further.
Inset a hex wrench into the valve and turn it
about a 1/4 turn to release some refrigerant
into the system. Once the needle moves,
close
the valve. The system is now partially
pressurized.
Wait for a few minutes to make sure that
there is no change in pressure. The system is
ready to be fully pressurized.
Unscrew the blue charge hose from the
service port quickly to minimize the release of
refrigerant
through
the Schrader valve.
Remove the cap from the low pressure
master
valve
(the larger valve). Using the hex
wrench,
open both valves until the
y
hit
their
stops. The
system is now pressurized.
Screw back all three caps on all valves and
ports and
tighten
them by hand.
Note on Adding Refrigerant
(R410a)
ADDITIONAL REFRIGERANT PER PIPE LENGTH
Depending on the length of the installed piping, you may need to add additional refrigerant to
your system.
The unit comes pre-charged for
Nx
25' (7.5m) of piping with R410a type refrigerant.
The additional refrigerant to be charged can be calculated using the following formula:
Connective
Pipe Length (
ft
)
Air Purging
Method
Additional Refrigerant
Vacuum Pump
None
>
Nx25'
Vacuum Pump
Liquid Side: Ø
1/4"
(ø
6.35mm
)
(Pipe length – 25') x 0.16oz/ft
(Pipe length –
7.5m
) x 15g/m
Liquid Side: Ø
3/8"
(ø
9.52mm
)
(Pipe length – 25') x 0.32oz/ft
(Pipe length – 7.5m) x 30g/m
CAUTION
DO NOT
mix refrigerant types.
Air Evacuation
4.
5.
3.
2
.
6
.
SENA/18HF/MOZ
The dual zone unit doesn't come with master
valves. Each line has to be vacuumed separately
before opening the high and low pressure
valves which will release the refrigerant into the
system.
< Nx25'
Model number
Number of ports
N
Total Connective Pipe Length (ft)
SENA/18HF/MOZ
SENA/30HF/MOZ
SENA/36HF/MOZ
SENA/48HF/MOZ
2
3
4
5
50
75
100
125
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35