10/19
55908014-17
INTERCONNECTING PIPEWORK
1. The indoor unit has a low pressure charge of N
2
, which may be safely released into the atmosphere
before connection. The service valves on the outdoor unit should remain closed (IN, fully clockwise)
until pipework has been fitted and system evacuated.
2. Connecting the pipework
a. Remove the flare nuts from the suction and liquid service valves.
b. Ensure that the suction line is fully insulated: if an expansion line is used this should also be fully
insulated.
c. Place the flare nuts over the incoming pipework and flare the pipe ends. The use of a little
refrigeration oil on the flaring tool will help.
d. Connect the pipework between the units. Do not leave pipe ends, valves etc. open to the
atmosphere.
R407C is very hygroscopic and will absorb damaging levels of moisture if left open.
Always use two spanners when tightening the flare nuts to avoid twisting the pipes. Use a small
amount of refrigerant oil on the mating surfaces.
e. Sight glasses and filter driers are not necessary, but if required should be fitted between the
outdoor unit liquid shut off valve and the expansion device.
EVACUATING
1. Connect a vacuum pump to the service ports on the outdoor unit valves and evacuate the system to 1000
microns (1 Torr) or better and allow to be held for a minimum of 15 minutes.
2. Replace the caps on the service ports, (torque to 25NM).
ADDING REFRIGERANT
1. All units are fitted with head pressure control. The link wire across the orange terminals allows the fan
to operate at full speed. THIS SHOULD BE REMOVED AFTER CHARGING
2. If a manual HP cut-out is fitted, ensure that the reset button is depressed.
3. A 3 minute delay occurs between successive compressor operations.
4. R407C should be introduced through the Schrader valve on the indoor unit, or the service port on the
suction service valve on the outdoor unit. No other refrigerant must be used.
NOTE: LABEL R407C POE (supplied loose) TO BE FIXED ABOVE SERVICE VALVES.
CHARGE (g)
No extra POE oil needed with liquid lines.
Charges shown are for guidance: actual charge will depend on the individual application. It is recommended that
you charge to a sweat line on the outlet of the evaporator and/or a full sight glass if fitted.
Additional
charge
based on:-
25g per 350g of additional refrigerant to a maximum of 300g
NOTE: The new 17 Series CKC are pre-charged for a 3 metre pipe run with R407C Refrigerant. See
chart below. The old 23 Series CKC have a small nitrogen charge.
PLEASE CHECK BEFORE INSTALLATION.