Equipment And Components Under Pressure; Maintenance Safety Considerations - Carrier AquaSnap 61AF 022 Installation, Operation And Maintenance Instructions

1 - INTRODUCTION
The external relief valve must always be connected to drain
pipes for units installed in a closed room. Refer to the
installation regulations, for example those of European
standard EN 378 and EN 13136.
These pipes must be installed in a way that ensures that
people and property are not exposed to refrigerant leaks. As
the fluids can be diffused in the air, ensure that the outlet is
far away from any building air intake, or that they are
discharged in a quantity that is appropriate for a suitably
absorbing environment. Relief valve must be checked
periodically. See paragraph "Repair safety considerations".
If the relief valves are installed on a reversing valve
(changeover), this is equipped with a relief valve on each of
the two outlets. Only one of the two relief valve is in operation,
the other one is isolated. Never leave the reversing valve in
the intermediate position, i.e. with both ways open (locate the
control element in the stop position). If a relief valve is
removed for checking or replacement please ensure that there
is always an active relief valve on each of the reversing valves
installed in the unit.
Provide a drain in the drain pipe, close to each relief valve,
to avoid an accumulation of condensate or rain water.
All precautions concerning handling of refrigerant must be
observed in accordance with local regulations.
Accumulation of refrigerant in an enclosed space can displace
oxygen and cause asphyxiation or explosions.
Inhalation of high concentrations of vapour is harmful and
may cause heart irregularities, unconsciousness, or death.
Vapour is heavier than air and reduces the amount of oxygen
available for breathing. These products cause eye and skin
irritation. Decomposition products can be hazardous.
1.3 - Equipment and components under
pressure
These products incorporate equipment or components under
pressure, manufactured by Carrier or other manufacturers. We
recommend that you consult your appropriate national trade
association or the owner of the equipment or components under
pressure (declaration, re-qualification, retesting, etc.). The
characteristics of this equipment/these components are given on
the nameplate or in the required documentation, supplied with the
products.
The units are intended to be stored and operate in an environment
where the ambient temperature must not be less than the lowest
allowable temperature indicated on the nameplate.
Do not introduce significant static or dynamic pressure with
regard to the operating pressures used during operation or
for tests in the refrigerant circuit or in the heat exchange
circuits.

1.4 - Maintenance safety considerations

Carrier recommends the following drafting for a logbook (the table
below should not be considered as reference and does not involve
Carrier responsibility): :
Intervention Name of the
commissioning
Date Nature
(1)
engineer
(1) Maintenance, repairs, regular verifications (EN 378), leakage, etc.
Engineers working on the electric or refrigeration components must
be authorized, trained and fully qualified to do so (e.g. electricians
trained and qualified in accordance with IEC 60364 Classification
BA4).
All refrigerant circuit work must be carried out by a trained
person,fully qualified to work on these units. He must have been
trainedand be familiar with the equipment and the installation. All
welding operations must be carried out by qualified specialists.
61AF units use refrigerant R-407C. Special equipment must be
used when working on the refrigerant circuit (pressure gauge,
charge transfer, etc.).
Any manipulation (opening or closing) of a shut-off valve
must be carried out by a qualified and authorised engineer,
observing applicable standards (e.g. during draining
operations). The unit must be switched off while this is done.
Equip the engineers that work on the unit as follows:
Personal protection
equipment (PPE) (1)
Handling
Protective gloves,
eye protection,
safety shoe,
protective clothing..
Ear protection.
Filtering respirator
(1) We recommend to follow the instructions in EN 378-3.
(2) Performed in the presence of A1 refrigerant according to EN 378-1.
Never work on a unit that is still energized. Never work on
any of the electrical components, until the general power
supply to the unit has been cut.
If any maintenance operations are carried out on the unit,
lock the power supply circuit in the open position and secure
the machine upstream with a padlock.
If the work is interrupted, always ensure that all circuits are
still deenergized before resuming the work.
ATTENTION: Even if the unit has been switched off, the power
circuit remains energized, unless the unit or circuit disconnect
switch is open, and remote start-up is still possible.
Refer to the wiring diagram for further details. Attach
appropriate safety labels.
If any work is carried out in the fan area, specifically if the
grilles or casings have to be removed, cut the power supply
to the fans to prevent their operation. It is also rcommended
to block the rotation of the blades during the work.
It is recommended to install an indicating device to show if
part of the refrigerant has leaked from the valve. The presence
of oil at the outlet orifice is a useful indicator that refrigerant
has leaked. Keep this orifice clean to ensure that any leaks
are obvious. The calibration of a valve that has leaked is
generally lower than its original calibration. The new
calibration may affect the operating range. To avoid nuisance
tripping or leaks, replace or re-calibrate the valve.
Applicable
Verification
national
Organism
regulations
Operations
maintenance, Welding or
service brazing
X X
X
(2)
X
X
X