EVOSTA2 25-105/130 SOL (1/2") Electronic circulator for solar systems DAB.EVOSTA2 SOL

Product detailed description

Electronic circulators are essential in solar thermal systems where precise control of flow and pressure is required to maximise energy efficiency and system performance. The EVOSTA2 25-105/130 SOL is specifically designed for integration into solar heating systems, where it manages the circulation of heat transfer fluid between the collector array and the storage tank. These systems are commonly found in residential and commercial buildings with solar thermal installations, including single-family homes, apartment blocks, and industrial facilities with dedicated solar heating loops. The circulator is installed in a closed-loop system where it must operate reliably under varying thermal conditions and fluid properties.

Proper sizing and installation are critical to ensure the circulator operates within its specified parameters. The system must be designed to accommodate the flow and pressure capabilities of the pump, while also considering the thermal expansion and contraction of the piping and components. The pump is typically mounted in a horizontal orientation to ensure stable operation and ease of maintenance. It is important to verify the compatibility of the pump with the system's control logic, especially if the installation includes external sensors or control units for monitoring and adjusting the flow based on solar irradiance and storage tank conditions.

Technical parameters

Maximum working pressure	10 bar (1000 kPa)
Voltage	1x230 V/50/60 Hz
Operating range	0 to 4 m³/h with a head up to 14.5 m
Fluid temperature range	-10 °C to +110 °C (130 °C at 60 °C ambient temperature)
Protection class	IPX4
Insulation class	F
Code	60188451
Brand	IVAR

The technical parameters define the operating envelope of the EVOSTA2 25-105/130 SOL. A maximum working pressure of 10 bar ensures the pump can handle typical pressures in solar systems, while the flow range of 0 to 4 m³/h allows for variable-speed control to match the system demand. The temperature range of -10°C to 110°C (with a 130°C limit at 60°C ambient) means the pump can handle both cold and hot fluid conditions. These parameters are essential for selecting the correct model based on the system's hydraulic and thermal requirements.

Installation and connection

Installation of the EVOSTA2 25-105/130 SOL requires a horizontal mounting position to ensure proper alignment of the motor shaft and to prevent mechanical stress. The pump is connected via 1/2 inch threaded ports, which must be verified for compatibility with the system piping. A 1.5 m power cable is included for the PWM-controlled version, allowing for flexible placement of the control unit. Before commissioning, the installer should check the alignment of the pump with the system, ensure the motor shaft is manually rotatable, and confirm that the pressure sensor is correctly positioned to detect system load changes.

Common installation errors include incorrect orientation of the pump, failure to bleed the system before operation, and neglecting to secure the mounting brackets properly. These issues can lead to reduced efficiency, premature wear, or system failure. It is also important to ensure that the pump is installed in a location that allows for easy access to the control panel and the bleed screw for routine maintenance.

Compatibility and accessories

The EVOSTA2 25-105/130 SOL is compatible with solar thermal systems that use clean, non-corrosive fluids with properties similar to water. It is not suitable for systems with high viscosity or those containing mineral oils. The pump can be integrated with external control units that provide a PWM signal for speed adjustment. Additional accessories such as pressure sensors, temperature probes, and control modules may be required for full system automation. No related products are listed for this model.

Technical background for designers

The EVOSTA2 25-105/130 SOL operates using a permanent magnet synchronous motor controlled by an integrated frequency inverter. This allows for variable-speed operation, where the pump adjusts its output based on the system's pressure and flow requirements. The pump housing is made of cast iron with cathodic protection coating, while the casing is stainless steel, providing resistance to corrosion and mechanical stress. The pump is designed to handle fluids with up to 50% glycol content, making it suitable for antifreeze solutions commonly used in solar systems.

The integration of the pump into the system requires consideration of the hydraulic loop's resistance, the thermal expansion of the piping, and the control logic of the solar system. The pump's efficiency is influenced by the cleanliness of the fluid, the alignment of the motor and pump shaft, and the stability of the electrical supply. Regular inspection of the motor insulation and the integrity of the sealing surfaces is recommended to ensure long-term performance.

Service and operation

During operation, the pump automatically adjusts its speed based on the detected pressure changes in the system, ensuring optimal efficiency. No scheduled service intervals are specified in the technical data. Routine maintenance should include checking the motor insulation for signs of degradation, verifying the tightness of the mounting bolts, and ensuring the bleed screw is free from blockage. The pump should be inspected for unusual noise or vibration, which may indicate misalignment or bearing wear.

For long-term reliability, the pump should be operated within its specified temperature and pressure limits. If the system is to be left idle for extended periods, it is advisable to drain the pump and apply a protective coating to the internal surfaces to prevent corrosion. The pump's IPX4 rating means it is protected against splashing water but not for outdoor use without additional enclosure.

Frequently asked questions

Can the EVOSTA2 25-105/130 SOL be used with glycol-based fluids?
Yes, the pump is suitable for fluids with up to 50% glycol content, provided they are chemically neutral and have properties similar to water.

Is the pump compatible with external control units?
Yes, the PWM-controlled version allows for integration with external control units that provide a speed adjustment signal.

Can the pump be installed in a vertical orientation?
No, the pump must be installed in a horizontal position to ensure proper alignment and operation of the motor shaft.

What is the maximum allowable temperature for the fluid?
The pump can handle fluid temperatures up to 110°C, with a 130°C limit if the ambient temperature is 60°C.