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IOM_UMXCBA-UMXCA_801.1a4502.2_208027_200201_EN
UMXCBA/UMXCA
CONDENSER UNITS WITH
COMPRESSOR AND AXIAL FAN
INSTALLATION
REFRIGERATION CONNECTIONS
Damages caused by a wrong installation of the refrigeration connections between the
indoor and the outdoor units will not be covered by the warranty.
A wrong installation may entail the following sources of problems:
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Penetration of air, water or any type of object or animal.
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Pipes that are too thick or too thin.
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Strangled or poorly brazed tubes.
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Not complying with the current local laws because of a wrong layout and problems of aestheticism of the
façades, etc.
Likewise, the above mentioned consequences may have an impact on:
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Speed of the refrigerant inside the pipe (too high or too low).
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Migration and no return of the compressor oil.
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Noises.
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Explosive breaks of the pipes.
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Contamination due to refrigerant leakage (greenhouse gas).
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Break of the solenoid valves or the expansion valves.
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Increased electrical consumption and decreased performance and capacity.
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Decreased operation limits. The unit might even become completely inoperative.
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Breakage of the compressor or shortening of its operation lifetime.
Guidelines for the correct installation of the refrigeration connections
1. Select a suitable place and prepare the correct settlement of the units. Determine the length of the refrigeration lines
between the units.
2. Calculate the dimensions of the pipes (diameters, lengths) and the necessary couplings for the installation.
Use as a reference the nº 207682 document (REFRIGERATION LINES DESIGN (R410a)).
3. Before starting installation, control that the inside part of the tubes are clean and humidity proof. Use preferably long
radius curves, do not produce throttles when handling the tube.
4. Pipe installation:
- Cut the tube with a tubbing cutter and then remove the burr and recalibrate the
diameter that has been reduced. Recalibrate with interior gauge or tube
expander. Do not use file, knife, or any other non-specialized tool that could leave
particles inside the pipe.
- Reduce the number of brazing and remember that it should always be of the
strong type. In compliance with local laws, the welder must be an authorized person. A bad weld can cause dirt inside
the pipe, more or less explosive blowouts that may cause third-party damage, pipe obstruction, refrigerant leakage, etc.
Remember that the tubes to be brazed must be clean without oil and refrigerant. Do not forget to make dry nitrogen
circulate in the interior without pressurizing and heat the male pipe primarily to ensure a good penetration.
5. The connection of the pipes to the machines can be threaded or brazed. Check the tightness after the connections.
6. The most common threaded connections in small pipes are the Flare type (flared) connections. A bad Flare connection
will entail leaks and/or blowouts. When doing the flare, it is essential to clean the burr of the tube properly to avoid cracks,
and do not leave the pipe wall very thin and without consistency by tightening too much.
Correct
Too big
Very small
Sloped
Cracked
Very thin or
uneven wall
Internal
scratches
7. Make the vacuum to the installation and the units that are not charged with refrigerant. Once the vacuum
pump stops, check that the vacuum remains during 20 min., a proper vacuum will be at an absolute pressure
of 2 hPa (2 mbar) or less.
Humidity or water in the installation may cause irreversible damages to the compressor and other devices
of the circuit. Liquid water cools and boils when the vacuum reaches its vapor pressure and does not allow
it to do so correctly until it freezes, once the water is frozen it does not boil but it is much more difficult to
remove and detect. To avoid the freezing of the water, it is advisable to make a soft and prolonged
vacuum and not make a fast vacuum with very powerful pumps.
8. Open all the keys and load with the refrigerant indicated on the nameplate. If it is not included in the machine,
add the additional load due to the length and thickness of the pipes. Follow current legislation regarding who
and how can handle the refrigerant.
9. Check for leaks during the first operation hours and schedule maintenance after the first month.