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Merlin now even more profitable and necessary

Elster Kromschröder optimizes Merlin 5064 V3 and V4 controllers

Elster Kromschröder optimizes Merlin 5064 V3 and V4 controllers

Osnabrück, March 2012.

In response to permanent changes in market requirements, Elster Kromschröder again recommends its controller series. Today, ever more stringent demands as regards energy consumption make using the Merlin 5064 V3 and V4 even more profitable. Thus, heating controller V3 can control up to eight boilers in a cascade with individual modulation control, while the Merlin V4 is ideal for controlling heat pumps, including optional integration of solar systems and biomass boilers.

In addition to the classic use as a heating controller for one- and two-stage boilers and systems with up to three heating circuits, customers increasingly request the possibility for controlling even more heating circuits (e.g. in central heating systems) and for controlling boilers to meet individual demands. For this, Merlin 5064 V3 offers a wide range of options: up to eight modules for switching (On/Off) or modulating boilers, even with varying capacity, can be controlled directly via the bus communication. The cascade control algorithm of the Merlin 5064 V3 ensures optimal capacity utilization at all times, resulting in reduced consumption and thus lowering costs. Even boilers using electronics produced by another manufacturer can, for the most part, be controlled. For wall-mounted boilers supporting an OpenTherm input, an interface is available which allows the Merlin 5064 V3 to communicate directly with the boilers and also to control them in cascade. Merlin offers the possibility to control boilers equipped with an analogue input (0 – 10 V) by transmitting the temperature setpoints to the boiler and then determining the modulation depth. Heat generators using different fuels such as oil, gas or pellets can be controlled optimally in On/Off or modulating mode.

The Merlin 5064 V4 controller, which is also suitable for wall mounting and can be operated in several languages, has been developed especially for heat pumps and the integration of solar systems. The illuminated, alphanumeric matrix display guides the user through the settings levels in the language of his choice, the respective selection option thus being displayed in text form. Therefore, the wide range of functions offered by this controller can be programmed in a particularly intuitive way. The heat pump controller is configured via a system selection function that automatically preconfigures all relevant settings. Up to four heat generators can be controlled directly in cascade using the Merlin 5064 V4. They are enabled using four floating relays. In addition to the time programs, the logic circuits for monovalent or bivalent operation have also been taken into account. Not only can the four relay outputs be used to control heat pumps, but they can also be used to control optional heat generators; Merlin 5064 V4 allows for so-called hybrid solutions (boiler plus heat pump).
The controller has a 0 – 10 V output for feedforwarding the temperature setpoint. Operation of the heat pump can also be prevented externally (e.g. by the electricity supplier) via a dedicated contact. The controller Merlin 5064 allows systems to be expanded to a maximum of 15 mixed zones. The possibility of integrating other alternative energies into the heating system – for example, solar systems – makes this controller particularly interesting.


Please submit editorial queries to:

Elster Kromschröder, Comfort Controls, Heinz Thiemann

 +49 5151 9572-310




About Elster GmbH

Elster GmbH, Kromschröder Osnabrück is one of the leading manufacturers of cutting-edge products and system solutions for safeguarding, measuring and controlling gases. With domestic and commercial gas meters, as well as safety valves and control components for heating equipment and for industrial use, the company offers a wide range of services, supported by a global sales and service organisation.


About Elster Group

Elster Group is the world’s largest supplier of metering technology for gas, water, heat and electricity consumption and is a leader in automated meter reading (AMR). The group employs around 7,000 staff and has operations in 38 countries worldwide, focused in North and South America, Europe, Africa, the Middle East and Asia. Elster’s high-quality products and systems reflect the wealth of knowledge and experience gained from more than 170 years in the industry.

More Information:

Heinz Thiemann

Elster Kromschröder, Comfort Controls, Heinz Thiemann

 +49 5151 9572-310



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Subject: Merlin 5064 V3 + V4

Edition: 02.12

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