ERL-DAC | Expansion tank
Compressor-controlled expansion tanks
Traditional expansion tanks are used in heating plants in order to limit overpressures which are generated by the liquid's volume variation inside the closed circuit whenever temperature changes. In fact, the air cushion of the expansion tank serves as a “lung” according to a ratio established by Boyle law.
The DAC (Dynamic Air Cushion) system has been designed to solve in a simple, safe and economic way the problems that can occur to the heating plant designer in the following cases:
• Exceptionally high water volume in the plant;
• Limited dimension of the boiler room;
• Very reduced differences between the plant’s min./max. pressures.
In these cases, the possibility to exploit completely the tank's volume as a water reserve allows to save considerably both in the installation costs and in the management and maintenance ones. The groups of the ERL/DAC series allow to achieve this aim, since the expansion tank’s sizing is not calculated according to the maximum value of water acceptance in the tank (Boyle law), but only according to the total expansion volume of the water contained in the plant. The pressurisation level is constantly checked by the electronic control panel according to the min. and max. pressure set.
Standard version available at 10 bar.
On request, models can be built with pressure higher than 10 bar and with certification in compliance with the most important international standards (TÜV, ASME, etc.).
The ERL/DAC system is composed of:
• ERL - D series expansion tank, CE certified
• Microprocessor (MCP) control unit, CE certified with built-in compressor
• EPDM rubber bladder (300 and 500 litre models),
• The 750 to 5000 litre models are equipped with a “full volume” type bladder whose dimensions ensure an almost unlimited duration of the membrane, enabling work with almost no mechanical stress.
• Epoxy powder paint, grey (300 and 500 litre models),
• Solvent-based paint, grey (750 to 5000 litres models).
• 750 to 2000 litre models: version with upper tie rod.
• The 3000 and 5000 litre models are equipped with an upper and lower flange opening.
• Declaration of conformity to essential safety requirements outlined by Directive 97/23/EC (PED).
• Working temperature: -10° / +99°C.
• Maximum working pressure: 10 bars
2 years warranty.