Carrier 50HB Manual page 17

Horizontal package air conditionners
Compressor
In the case of compressor replacement:
- Disconnect the unit from power supply.
- Completely empty the load of refrigerant using a specifi c recovery
unit for R-410A
- Disconnect electrically the compresor.
- Carefully unsolder the suction and discharge piping.
- The compressor is fi xed onto the platform with 4 screws. Unscrew
the fi xings.
- Place the new compressor and check that it has a suffi cient oil charge.
Warning: when tightening the compressor screws, please consult
the maximum torque that can be applied.
If a torque wrench is not available, tighten them until noticing
resistance, then tighten the screws by turning them 3/4 of a revolution.
- Solder the suction and discharge piping.
- Connect the compressor in accordance with the circuit diagram.
- Make vacuum and next, reload the gas into the unit according to
load data provided in the technical characteristics table and in the
unit's data plate.
Dehydrant fi lter
- The fi lter function is the preserve the cooling circuit clean and without
humidity, neutralizing the acids that can be found in the cooling circuit.
Verify dirt measuring the difference in temperature at the tubing level,
at the inlet and at the outlet of the dehydrant.
- If necessary, replace.
Oil
Oils used for cooling machines do not post any threat to one's health
if used while following the usage guidelines:
- Avoid any unnecessary manipulation of the elements covered in oil.
Use protection creams.
- Oils are fl ammable and must be stored and handled with precaution.
"Disposable" rags or towels used for cleaning must be kept away
from open fl ames and must be discarded by using the appropriate
procedure.
Dehydrating fi lter Compressor
- Jugs must be kept closed. Avoid using oil from an already-open jug
kept in poor conditions.
Both the oil type as well as the volume needed for each model are
stated in the characteristics table in chapter 3.
- Check the oil level and aspect. In case of a colour change, check
the oil quality using a contamination test.
- In the case of the presence of acid, water or metallic particles, replace
the affected circuit oil, as well as the dehydrant fi lter.
- In the event of an oil charge change, only new oil will be used, which
will be identical to the original oil and taken from a jug tightly closed
until the moment of the charge.
Refrigerant
Only qualifi ed personnel must perform a periodic tightness control, in
accordance with the regulation (CE) Nº 517/2014.
- The frequency of checks is no longer related to the load of refrigerant
but to its global warming potential:
Load kg x GWP = t CO2e
Carbon dioxide equivalency (t CO2e ) is a quantity that describes, for
a given mixture and amount of greenhouse gas, the amount in tonnes
of CO2 that would have the same global warming potential (GWP).
Please, consult data of carbon dioxide equivalency (t CO2e) provided
in the technical characteristics table (chapter 4).
- Operators shall ensure that the unit is checked for leaks ad minima
according to the following frequency:
• t CO2e < 5 ............ not subjected
• t CO2e 5 to 50 ...... every year
• t CO2e 50 to 500 ... every 6 months
• t CO2e > 500 ......... every 3 months
- Where a leakage detection system has been installed the frequency
of checks is halved.
Note: Never forget that the cooling systems contain liquids and vapours
under pressure. The service pressure of R-410A is approximately 1.5
higher than that of R-407C.
- All necessary precautions must be taken during the partial opening
of the cooling circuit. This opening entails the discharge of a certain
amount of refrigerant to the atmosphere. It is essential to limit this
quantity of lost refrigerant to a minimum by pumping and isolating
the charge in some other part of the circuit.
- The refrigerant fl uid at low temperature can cause infl ammatory
injuries similar to burns when contacting the skin or eyes. Always use
safety goggles, gloves, etc. when opening ducts that may contain
liquids.
- The refrigerant in excess must be stored in appropriate containers
and the amount of refrigerant stored at the technical rooms must be
limited.
- Refrigerant barrels and deposits must be handled with precaution
and visible warning signs must be placed to attract attention over
the risks of intoxication, fi re and explosion linked to the refrigerant.
- At the end of its useful life, the refrigerant must be retrieved and
recycled as per the current regulations.
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