RHOSS TCCEY 114 Instrucciones De Uso página 20

Winter: the Compact-Y unit with 4 shutter steps allows for significant
seasonal electric energy savings. Our calculations show that the
seasonal consumption is equivalent to that of a CLASS Amachine.
Y
7800
7200
6600
6000
5400
4800
4200
3600
3000
2400
1800
1200
600
0
9
10
11
Year divided into months (1 January, 2 February, etc.)
X
Power consumption (kWh)
Y
Single-compressor unit with fixed Set-point.
Bi-compressor unit, 2 shutter steps with fixed set-point.
Bi-compressor Compact-Y unit, 3 shutter steps with
sliding set-point.
Year-round: efficiency during the annual operation of the unit in heat
pump mode. AdaptiveFunction Plus, with the "Economy" function,
allows the chiller to run on energy- saving programmes while still
providing the required level of service.
Y
5,000
4,500
4,000
3,500
3,000
2,500
2,000
1
2 3
4
Year divided into months (1 January, 2 February, etc.)
X
Energy efficiency kWh supplied/kWh absorbed
Y
Bi-compressor Compact-Y unit, 3 shutter steps with sliding
set-point.
Bi-compressor unit, 2 shutter steps with fixed set-point.
Single-compressor unit with fixed Set-point.
Analysis conducted in an office building in Milan, comparing the
operation of:
 a reversible single-compressor heat pump unit that works with a
fixed set-point (7°C in summer and 45°C in winter);
 a reversible heat pump unit with two compressors of equal power,
that work on the same cooling circuit with a fixed set-point (7°C in
summer and 45°C in winter);
 a Compact-Y unit with three shutter steps and AdaptiveFunction
Plus logic, which operates with a scrolling set-point (range between 7
and 14 °C in the summer, and between 35 and 45°C in the winter).
2. High precision: "Precision" Option
In this operating mode, the unit works at a fixed set-point and, thanks
to the water flow temperature control and the advanced control logic,
at loads ranging between 50% and 100%, it is possible to guarantee
an average fluctuation from the utility water supply temperature of
approximately ± 1.5°C with respect to the set-point value compared
to an average fluctuation of approximately ± 3°C, which is normally
obtained with standard return control.
12
1 2
3 4
X
5 6
7 8
9 10 11 12
X
Therefore, the "Precision" option guarantees precision and reliability
in all applications that require a controller that guarantees a more
accurate constant water supply temperature, and where particular
humidity control is required. However, it is always recommended to
use a storage tank with greater system water content in process
applications to guarantee high system thermal inertia.
s
Fluctuation
s
Load
FC
Unit with storage tank, 4 litres/kW in the system and return
control.
Unit with storage tank, 2 litres/kW in the system and flow
control with "Precision" AdaptiveFunction Plus function
The graph illustrates the water temperature fluctuations from the set
value in various load fractions, thereby showing how a unit with flow
control and the AdaptiveFunction Plus "Precision" function guarantees
greater utility water supply temperature precision.
Virtual Tank: guaranteed reliability, even with water only in
the pipes
Low water content in the system can cause chiller/heat pump units to
work inconsistently, causing system instability and poor performance.
Thanks to the Virtual Tank function, this is no longer a problem. The
unit can operate in systems with just 2 litres/kW in the pipes given that
the control is able to compensate for the lack of inertia specific to a
water storage tank by ''muffling'' the control signal, preventing the
compressor from switching on and off in an untimely fashion and
reducing the average fluctuation of the set-point value.
T
14
12
10
8
6
4
2
0
2000 3000 4000
Water temperature (°C)
T
Time (s)
t
Set-point temperature
T1
Delivery temperature with Virtual Tank
Delivery temperature without Virtual Tank
The chart shows the various chiller outlet temperatures referred to an
operating capacity of 80%. We can see how the temperatures of the
unit with AdaptiveFunction Plus logic and Virtual Tank function is far
less varied and more stable over time, with average temperatures
closer to the working set-point compared to the unit without the Virtual
Tank function. We can also see how the unit with AdaptiveFunction
Plus logic and Virtual Tank function switches the compressor on less
often over the same period of time, with obvious advantages in terms of
energy consumption and system reliability.
20
SECTION I : USER
5000 6000 7000 8000
FC
T1
t
9000