Instructions
118U3276C - AN18658643414604-001401 | 5
© Danfoss | DCS (CC) | 2020.06
ches and relief valves don’t exceed the maximum
service pressure of any system component.
• Verify that all electrical connections inside the
condensing unit are properly fastened as they
could have worked loose during transporta-
tion.
• When a crankcase heater is required, the unit
must be energized at least 12 hours before ini-
tial start-up and start-up after prolonged shu-
tdown for belt type crankcase heaters.
• The unit is equipped with a main switch with
overload protection. Overload protection is
preset from factory, but it is recommended to
check the value before taking the unit in ope-
ration. The overload protection value can be
found in the wiring diagram in the unit front
door.
• Check if discharge temperature sensor is firm
and has proper contact with discharge pipe.
12 – Start-up
• Never start the unit when no refrigerant is char-
ged.
• All service valves must be in the open position.
• Rotalock valve on the receiver must be tur-
ned 1 round to close direction to get the right
condensing pressure for the pressure transmit-
ter
• Check compliance between unit and power
supply.
• Check that the crankcase heater is working.
• Check that the fan can rotate freely.
• Check that the protection sheet has been remo-
ved from the backside of condenser.
• 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.
• Eventual reverse rotation of a 3-phase compres-
sor can be detected by following phenomena;
the compressor doesn’t build up pressure, it has
abnormally high sound level and abnormally
low power consumption. P05 models are equip-
ped with a phase-reversal relay and compressor
doesn’t start, the compressor doesn’t build up
pressure, in case of wrong phase sequences.
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.
13 – 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.
• When a sight glass is provided observe the oil
level at start and during operation to confirm
that the oil level remains visible.
• 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.
• For P02 version models (OP-xxxxxxxxxP02E) :
- Check sight glass and make sure no bubbles in
liquid line for proper liquid injection.
- When o30 is set 19= R404A or 40=R448A or
41=R449A and readout U26 > 125 in controller,
check and make sure liquid injection is ON. Eco-
nomizer inlet pipe should be cold.
• Do not overcharge the system.
• Follow the local regulations for restoring the
refrigerant from unit.
• 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.
14 – Emergency running without controller
In case of controller failure, the condensing unit
can still be operated when the controller standard
wiring (picture 4) is modified into a temporary
wiring (picture 5) 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 24
(room thermostat DI1) and put them together
with an insulated 250 Vac 10mm² terminal
bridge.
• Remove wire 25 (room thermostat DI1) and
wire 11 (compressor supply) and put them
together with an insulated 250VAC 10mm² ter-
minal bridge.
• Remove wire 6 and connect it with terminal
bridge for wire 11 and 25. A fan pressure switch
or fan speed controller can be connected in
series to wire 6.
• Remove wire 14 (crankcase heater) and connect
it to the compressor contactor terminal 22.
• Remove wire 12 (supply crankcase heater), ex-
tend this wire by using an 250 Vac 10mm² termi-
nal 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).
15 – Maintenance
Always switch off the unit at main switch be-
fore opening the fan door (s).
Internal pressure and surface temperature
are dangerous and may cause permanent injury.
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.
The condenser must be checked at least once a
year for clogging and be cleaned if deemed ne-
cessary. Access to the internal side of the conden-
ser takes place through the fan door. Microchan-
nel coils tend to accumulate dirt on the surface
rather than inside, which makes them easier to
clean than fin-&-tube coils.
• Switch off the unit at main switch before ope-
ning the fan door.
• Remove surface dirt, leaves, fibres, etc. with
a vacuum cleaner, equipped with a brush or
other soft attachment. Alternatively, blow com-
pressed air through the coil from the inside out,
and brush with a soft bristle. Do not use a wire
brush. Do not impact or scrape the coil with the
vacuum tube or air nozzle.
• Before closing the fan door, turn the fan blade
in a safe position, to avoid that the door hits the
fan.
If the refrigerant system has been opened, the
system has to be flushed with dry air or nitrogen
to remove moisture and a new filter drier has to
be installed. If evacuation of refrigerant has to be
done, it shall be done in such a way that no refrige-
rant can escape to the environment.
16 – Declaration of incorporation
• Pressure Equipment Directive 2014/68/EU
EN 378-2:2016 - Refrigerating systems and Heat
Pumps - Safety and environmental requirements-
Parts 2: Design, construction, testing, marking
and documentation.
Low Voltage Directive 2014/35/EU EN 60335-
1:2012 + A11:2014- Household and similar elec-
trical appliances-Safety-Part 1: General requi-
