VARIO fresh-nova cascade ExOpt

Exergy-optimized cascade VARIO fresh-nova ExOpt: 26 types, 58-855 l/min nominal capacity
Separation of DHW and circulation heating with separate pipe routing for minimum return temperatures
Hygienic, energy-saving instantaneous water heaters; heat supply via stratified storage tank or buffer tank
Efficient counterflow plate heat exchangers and AI control VarCon211 (neural network) for low pressure losses and automatic optimization

Areas of application

The VARIO fresh-nova cascade ExOpt range of appliances comprises exergy-optimized, electronically controlled cascaded fresh water heaters with 26 types in 17 output sizes in the nominal output range from 58 to 855 l/min. Thanks to the exergy-optimized wiring, the tasks of domestic hot water heating and circulation water heating are separated in terms of equipment technology and enable the lowest possible return temperatures thanks to separate pipe routing.

As instantaneous water heaters, the appliances enable hygienic and energy-saving domestic hot water preparation in domestic installations. Heat is typically supplied by a stratified tank or standard buffer tank.

Generously dimensioned counterflow plate heat exchangers ensure low return temperatures and low pressure losses. The VarCon211 electronic controller uses an adaptive neural network, a method from the field of artificial intelligence (AI), to automatically optimize the control quality for given local operating conditions.

Intelligent networking

Conserving resources

Future-proof

Functions

The standard functions include

DHW and remote circulation water heating
the circulation pump control
Cascade function and rotation and
one parameterizable switching function per device.

Domestic hot water heating
The VARIO fresh-nova heats drinking water using the flow-through method. When a hot water tap is opened, the integrated controller registers the flow rate sensor and starts the charging pump at the correct speed. This pumps water from the cylinder through the stainless steel plate heat exchanger in the quantity that exactly covers the heating requirement for hot water preparation.
The hot water temperature can be adjusted to demand via 6 switching points per day of the week.
Important information for fresh water heating is continuously stored and processed in the controller's neural network. This enables it to “learn” and adapt its behavior to the respective operating conditions.

Remote circulation water heating
Exergy-optimized switching means separating the heating tasks in terms of equipment technology:
- W appliances are used purely for domestic hot water heating,
- Z appliances are used to heat circulation water and domestic hot water at full load.
Separate pipe routing results in the lowest possible return temperatures (exergy-optimized). At full load, the return flow of the Z appliances is fed into the lower storage tank area via a so-called return flow switchover depending on the temperature. The switchover is controlled by the switching function of an appliance controller.

Circulation mode
The integrated circulation pump control recognizes demand, time and temperature-dependent operating modes. Suitable options with 6 switching points per weekday allow hygiene requirements, energy saving and convenience to be combined.

Cascade function and rotation
The cascade functionality is realized by starting from the first device with increasing
load, the motor valve of the downstream device is opened. As the load decreases, the
Motor valves are closed again in reverse order. I.e. the last switched on
The appliance is switched off first (last-in-first-out). After definable flow rates
the ranking of the devices is swapped (cascade rotation) in order to ensure even utilization.
of all devices and to achieve the desired water exchange.

Parameterizable switching function
The switching function of the VarCon211 compact controller extends the range of functions to include pre-assembled controller variants for storage tank charging or, alternatively, a general thermostat. In cascades, switching functions corresponding to the number of devices are available, allowing a wide range of control concepts to be implemented, which are often helpful when connecting to the overall system.

Application

The VARIO fresh-nova ExOpt cascade range is ideal for use in apartment buildings and commercial buildings with high hot water loads, for new builds and refurbishment of heating systems with a view to hygiene and energy saving.