11 - MAJOR SYSTEM COMPONENTS
11.12 - Refrigerant
TD units are charged with liquid R-407C refrigerant, a non-
azeotropic refrigerant blend consisting of 23% R-32, 25% R-125
and 52% R-134a and characterised by the fact that when there
is a change in state, the temperature of the liquid/vapour mixture
is not constant, as with azeotropic refrigerants.
All checks must be pressure tests, and the appropriate pressure/
temperature ratio table must be used to determine the
corresponding saturated temperatures (saturated bubble point
curve or saturated dew point curve).
Leak detection is especially important for units charged with
refrigerant R-407C. Depending on whether the leak occurs in
the liquid or in the vapour phase, the proportion of the different
components in the remaining liquid is not the same.
NOTE: Regularly carry out leak checks and immediately
repair any leak found. If there is a leak in the plate heat
exchanger, this part must be replaced.
The refrigerant must always be recharged in the liquid phase
into the liquid line.
The refrigerant cylinder must always contain at least 10% of its
initial charge.
For the refrigerant quantity per circuit, refer to the data on the
unit name plate.
11.13 - High-pressure safety switch
TD units are equipped with automatically reset high-pressure
safety switches, calibrated to 3130 kPa relative pressure (soft
alarm is manually reset).
NOTES: Monitoring during operation:
-
Follow the regulations on monitoring pressurised
equipment.
-
It is normally required that the user or operator sets up
and maintains a monitoring and maintenance file.
-
Follow the control programmes of EN378, annex D.
-
If they exist follow local professional recommendations.
-
Regularly inspect the condition of the coating (paint) to
detect blistering resulting from corrosion.
-
Regularly check for possible presence of impurities (e.g.
silica grains) in the heat exchange fluids. These impurities
maybe the cause of the wear or corrosion by puncture.
-
Filter the heat exchange fluid check and carry out internal
inspections as described in EN378, annex C.
-
The reports of periodical checks by the user or operator
must be included in the supervision and maintenance
file.
REPAIR
Any repair or modification, including the replacement of
moving parts:
-
must follow local regulations and be made by qualified
operators and in accordance with qualified procedures,
-
must be made in accordance with the instructions of the
original manufacturer. Repair and modification that
necessitate permanent assembly (soldering, welding,
expanding etc.) must be made using the correct
procedures and by qualified operators.
An indication of any modification or repair must be shown
in the monitoring and maintenance file.
AQUACIAT
CALÉO™
TD
EN-32
