Manual selection, installation and maintenance
8
Roof-top units -
RTE series
-
Description of component
S
Refrigerant circuit
COMPRESSOR
Hermetic scroll compressors, equipped
with a crankcase heater as standard acces-
sory.
The resistor is powered automatically when
the unit pauses, provided the power supply
is not turned off.
EXTERNAL HEAT EXCHANGER
Made of copper tubes and aluminium fins,
fixed by mechanical expansion of tubes.
High-efficiency type; grooved pipe and
corrugated fins for heat pump, smooth pipe
and turbo fins for cooling-only version.
INTERNAL HEAT EXCHANGER
Made of copper tubes and aluminium fins,
fixed by mechanical expansion of tubes.
High-efficiency type; grooved pipe and
corrugated fins for heat pump, smooth pipe
and turbo fins for cooling-only version.
LIQUID SEPARATOR
(heat pump ver-
sions only)
Located on the compressor suction side
to offer protection against possible returns
of liquid refrigerant, flooded start-ups, and
operation in the presence of liquid.
THERMOSTATIC VALVE
The valve, with equaliser at the evaporator
outlet, regulates the gas flow to the evapo-
rator according to the thermal load, ensu-
ring a sufficient degree of superheating of
intake gas.
DRIER FILTER
Mechanical filter made from ceramic and
hygroscopic material, designed to capture
impurities and all residual moisture in the
cooling circuit.
LIQUID INDICATOR
Indicates the level of the refrigerant gas
charge and the presence of moisture in the
cooling circuit.
SOLENOID VALVE
Intervenes when the compressor is stopped
to stop the flow of refrigerant gas to the
evaporator.
S U C T I O N S I D E L I Q U I D A N D
DISCHARGE GAS SHUT-OFF VALVES
(cooling version only)
These valves intercept the flow of refrige-
rant to allow supplementary maintenance
work.
REVERSE CYCLE VALVE (heat pump
only)
Reverses the flow of refrigerant on chan-
ging from Summer to Winter operating
mode and during defrosting cycles.
BY-PASS SOLENOID VALVE (heat
pump only)
By-passes the thermostat valve during the
defrosting cycle.
COOLING CIRCUIT SAFETY VALVE
(080 - 200 only)
Set to 30 Bar, it intervenes to discharge
excess pressure if the pressure level rises
above normal .
UNIDIRECTIONAL VALVE (heat pump
only)
Allows refrigerant to flow in only one
direction
.
Frame and fans
CONDENSING FAN ASSEMBLY
The axial fans are statically and dynami-
cally balanced. The fan units are electri-
cally protected with thermal-magnetic cir-
cuit breakers and mechanically protected
with metal anti-intrusion grilles.
AIR-HANDLING FAN ASSEMBLY
Centrifugal fan with double inlet and for-
ward blades for greater performance and
quietness, balanced statically and dyna-
mically, activated by three-phase motors
coupled by trapezoidal belts and variable-
pitch pulleys only for the models from 080
to 200, directly coupled for the models
from 025 to 050, with manual control,
with standard electronic device
SUPPORTING STRUCTURE
The construction type for the air handling
side and for the condensing side is diffe-
rent according to the model:
• models 025,030,040,050: panels in
peraluman with insulation on the air han-
dling side with closed-cells expanded pol-
yethylene (30 kg/m
3
density)
• models 080,090,100,150,200: san-
dwich panels in peraluman, external and
internal, 25mm thickness with insulation
in injected polyurethane foam (42 m3/h
density) for side panels, for the roof of the
air handling side.
Safety and control device
CONTROL KEYPAD AND DISPLAY BY
THE UNIT
Gives complete control over the functions
of the unit. For more information, refer to
the user manual.
ELECTRIC PANEL
Includes power section, regulation of con-
trols and safety devices. Compliant with
CEI 60204-1 standards and Directives
EMC 89/336/CEE and 92/31/CEE gover-
ning electromagnetic compatibility.
ANTI-FREEZE PROBE (only with BC
accessory)
When the water temperature is +3°C the
specific software, present in the control
board, will open the 3-way dampers valve
completely and set the hot water into
circulation by means of an output digital
signal.
PRESSURE SWITCHES
Positioned on the high and low sides of
the refrigeration circuit. They cut off the
functioning of the compressor in the case
of abnormal operating pressures.
FLOW-METER (standard from model
080 to 200)
I t e n s u r e s t h a t w a t e r i s c i r-
c u l a t i n g a n d , i f i t i s n o t ,
shut’s down the unit. For models
from 025 to 050 it is only avai-
lable with the electrical battery.
HIGH AND LOW PRESSURE TRANSDU-
CERS
(optional for the cooling version
only)
Placed on the high and low pressure sides
of the cooling circuit, they allow to visuali-
se the pressure values on the display.
DOOR LOCK DISCONNECTO
R
For safety reasons it is only possible to
access the electric panel after cutting off
the power supply using the lever that
opens the panel itself. This lever can be
fastened with one or more locks during
maintenance operations, to prevent
power from being restored to the unit
accidentally
.
