Instructions
© Danfoss | DCS (CC) | 2018.06 | 5
FRCC.PI.041.A4.02
The electronic controller is factory preset for ope-
ration with refrigerant R449A. If another refrigerant
is used, the refrigerant setting must be changed.
Parameter r12 must be set to 0 before (software
main switch= off).
• Push the upper button for a couple of seconds.
The first parameter code appears.
• Push the upper or lower button to find parame-
ter code o30.
• Push the middle button until the value for this
parameter is shown.
• Push the upper or lower button to select the
new value: 17 = R507A, 19 = R404A, 21=R407A,
37=R407F, 40= R448A, 41= R449A.
• Push the middle button to confirm the selected
value.
• Go back to parameter r12 and change it to 1.
• If necessary change also parameter r23 to de-
sired suction pressure (°C/°F).
• Change parameter c33 for pump down value ac-
cording your needs.
10 – Verification before commissioning
Use safety devices such as safety pressure swit-
ch and mechanical relief valve in compliance with
both generally and locally applicable regulations
and safety standards. Ensure that they are opera-
tional and properly set.
Check that the settings of high-pressure swit-
ches and relief valves don’t exceed the maximum
service pressure of any system component.
• Verify that all electrical connections are proper-
ly fastened and in compliance with local regu-
lations.
• The crankcase heater must be energized at
least 12 hours before initial start-up and start-
up after prolonged shutdown to remove refri-
gerant in liquid phase from the compressor.
Remove DI1 plug from the controller to avoid
compressor start and turn ON the main switch
during this period.
• The unit is equipped with a main switch with
overload protection. Overload protection is pre-
set from factory, but it is recommended to check
the value before taking the unit in operation.
The overload protection value can be found in
the wiring diagram in the unit front door.
11 – Start-up
• Never start the unit when no refrigerant is
charged.
• All service valves must be in the open position.
• Check compliance between unit and power
supply.
• Check that the crankcase heater is working.
• Check that the fan can rotate freely.
• Balance the HP/LP pressure.
• Energize the unit. It must start promptly. If the
compressor does not start, check wiring confor-
mity and voltage on terminals.
• Reverse rotation of the 3-phase compressor
will be detected from the controller and can be
detected by following phenomena; the com-
pressor doesn’t build up pressure, it has ab-
normally high sound level and abnormally low
power consumption. In such case, shut down
the unit immediately and connect the phases
to their proper terminals.
• If the rotation direction is correct the low pres-
sure indication on the controller (or low pres-
sure gauge) shall show a declining pressure and
the high pressure indication (or high pressure
gauge) shall show an increasing pressure.
12 – Check with running unit
• Check the fan rotation direction. Air must flow
from the condenser towards the fan.
• Check current draw and voltage.
• Check suction superheat to reduce risk of slug-
ging.
• The optimum compressor suction superheat is
around 6K. The maximum allowed superheat is
30K.
Observe the oil level at start and during operation
to confirm that the oil level remains visible. Excess
foaming in oil sight glass indicates refrigerant on
the sump.
• Monitor the oil sight glass for 1 hour after
system equilibrium to ensure proper oil re-
turn to the compressor. This oil check has to
be done over the speed range to guarantee:
- a good oil return at low speed with minimum
gas velocity.
- a good oil management at high speed with
maximum oil carry over.
• Respect the operating limits.
• Check all tubes for abnormal vibration. Move-
ments in excess of 1.5 mm require corrective
measures such as tube brackets.
• When needed, additional refrigerant in liquid
phase may be added in the low-pressure side as
far as possible from the compressor. The com-
pressor must be operating during this process.
• Do not overcharge the system.
• Never release refrigerant to atmosphere.
• Before leaving the installation site, carry out a
general installation inspection regarding clean-
liness, noise and leak detection.
• Record type and amount of refrigerant charge
as well as operating conditions as a reference
for future inspections.
Compressor failure to build up pressure: Check all
bypass valves in the system to ensure that none
of these has been opened. Also check that all so-
lenoid valves are in their proper position.
• Abnormal running noise: Ensure the absence
of any liquid flood-back to the compressor by
means of measuring the return gas superheat
and compressor sump temperature. The sump
should be at least 6K above the saturated suc-
tion temperature under steady-state operating
conditions.
•
The high-pressure switch trips out: Check
condenser operations (condenser cleanliness,
fan operation, water flow and water pressure
valve, water filter, etc.). If all these are OK, the
problem may be due to either refrigerant over-
charging or the presence of a noncondensable
(e.g. air, moisture) in the circuit.
• The low-pressure switch trips out: Check eva-
porator operations (coil cleanliness, fan opera-
tions, water flow, water filter, etc.), liquid refri-
gerant flow and pressure drops (solenoid valve,
filter dryer, expansion valve, etc.), refrigerant
charge.
• Low refrigerant charge: The correct refrigerant
charge is given by the liquid sight glass indi-
cation, the condenser delta T in relation to the
refrigerant pressure tables (pressuretempera-
ture), the superheat and the subcooling, etc. (if
additional charge is deemed necessary, refer to
section 8).
13 – Emergency running without controller
In case of controller failure, the condensing unit
can still be operated when the controller stan-
dard wiring (WD1) is modified into a temporary
wiring (WD2) as described below.
This modification may be done by authorized
electricians only. Country legislations have to be
followed.
Disconnect the condensing unit from power
supply (turn hardware main switch off)
• Contact of Room Thermostat must be possible
to switch 250VAC.
• Remove wire 22 (safety input DI3) and wire 6
(fan supply) and put them together. A fan pres-
sure switch (e.g. KP5) or a fan speed controller
(e.g. XGE) can be connected in series to wire 6
• Remove wire 10 (drive start) and wire 24 (room
thermostat) and put them together
• Remove wire 11 (drive start) and wire 25 (room
thermostat) and put them together
• Remove wire 53 and 55 from drive terminals and
connect a 10kOhm potentiometer as below:
wire 1 to drive terminal 55
wire 2 to drive terminal 53
wire 3 to drive terminal 50
• Turn the knob of the potentiometer to middle
position, which corresponds approximately
compressor speed 50rps
• Remove wire 14 (crankcase heater) and connect
it to the compressor contactor terminal 22.
•
Remove wire 12 (supply crankcase heater),
extend this wire by using an 250 Vac 10mm²
terminal bridge and 1,0mm² brown cable and
connect it to compressor contactor terminal 21
•
Remove the large terminal block from the
controller terminals 10 to 19.
• Connect the condensing unit to power supply
(turn hardware main switch on).
• Adjust the potentiometer to get the desired
speed.
• Replace the controller as soon as possible.
14 – Maintenance
Always switch off the unit at main switch and
wait 4 minutes (capacitor discharge time) before
opening the fan door (s) to avoid electric shock.
Even when main switch is OFF voltage is available
on the income terminals of main switch and this
should be considered during maintenance and
service.
Internal pressure and surface temperature
are dangerous and may cause permanent inju-
ry.Maintenance operators and installers require
appropriate skills and tools. Tubing temperature
may exceed 100°C and can cause severe burns.
Ensure that periodic service inspections to
ensure system reliability and as required by local
regulations are performed.
To prevent system related problems, following
periodic maintenance is recommended:
• Verify that safety devices are operational and
properly set.
• Ensure that the system is leak tight.
• Check the compressor current draw.
• Confirm that the system is operating in a way
consistent with previous maintenance records
and ambient conditions.
• Check that all electrical connections are still
adequately fastened.
• Keep the unit clean and verify the absence of
rust and oxidation on the unit components,
tubes and electrical connections.
