Heat metering and balancing systems are playing  an important role in interventions aimed at reducing the energy consumption in buildings, both new and existing.

The correct tuning of the devices gives an optimal and efficient management of the heating and cooling systems present in every building unit.

What solutions should have to be chosen and what aspects should be considered, in order to achieve satisfactory practical results?

We asked Alberto Montibelli, Senior Technical Specialist at Giacomini. Giacomini is a company that has got  a strong experience gained internationally, and has developed a range of integrated products for heat metering and balancing of systems in large residential buildings.

Installations in large residential buildings

First of all Ing. Montibelli, what are the law requirements regarding the construction of systems in residential buildings?

“Following to European directives and (Italian) national legislation, there is an obligation to install thermal regulation systems and energy metering systems for every building unit, even for new buildings and for the renewed  buildings, with four or more housing units  using a common heating source".

In this context, what kind of technical solutions has the designer for this type of systems ?

“Two main classes of metering  systems can be distinguished: modules and satellites. These are two very different solutions “.

Heat metering systems: satellites and modules

What is the meaning of  the heat metering module?

“Heat metering modules are those devices installed close to the building units, that receive fluids directly and distribute thems from the thermal power plant: water for heating and cooling, hot and cold sanitary water. The module provides the functions of measuring consumption, balancing and general interception of the real estate unit. It is a very common technical solution in Italy “.

How do the heat metering satellites differ from each other?

“The satellites only receive water for heating and cold sanitary water production from the thermal boiler room.  Domestic hot water is produced locally thanks to the heat exchanger on board of  the satellite. In some specific  satellite versions, the double exchanger configuration  is adopted  in order to obtain a physical separation between the primary distribution network and the individual distribution circuits of each building unit. It is a widespread system approach,  especially in the presence of the heating district, or in systems oriented from the outset towards to this solution “.

What should the designer consider when choosing the heat meter systems?

“Depending on each real estate unit  systems, which may be very different from each other, the designer is called upon to choose the most suitable solution for heat metering, both in technical terms and in occupied spaces. Don’t  forget that the heat metering systems are located outside the apartments, usually in a condominium spaces near to the lift landings or at the entrance of each real estate unit. It is clear that in these contexts it is mandatory to reduce the overall dimensions. That is the reason why Giacomini offers different and variegated solutions, starting from the single-user modules, that manage a single apartment, to a more integrated and compact solutions where the module is capable to serve multiple housing units, with a great space saving, easy commissioning and a periodic inspection”.

According to the type of systems installed in the apartments, the designer must choose the most suitable accounting modules. What scenarios are there?

“The scenarios can be quite different. In the event that all apartments in the condominium are equipped with the same heating system, or heating and cooling, then the thermal power plant will be able to provide the technical fluids by itself , at the appropriate temperature and the heat-metering modules will simply receive them, to measure their consumption,  and distribute them to the apartments. In case of a big building or different heating systems inside building units, the situation changes.

Could you provide an example?

“Just think about the case of a large condominium building in which every familiar unit is equipped with a radiant system for heating and cooling assisted by dehumidification.  A critical issue immediately catches the technician’s attention: summer regulation of the delivery flow temperature. This is based on the dew point, which is specific to each living unit, because it depends on its population and the activity that takes place in there.  To respond effectively to this need, Giacomini proposes metering modules equipped with a mixing valve and re-launching circulator, for both single-user and multi-user units. In this way it is possible to manage the settings of each apartment perfectly and independently “.

Whereas, what happens in the area of satellites for heat metering? ….

 “The range goes from standard solutions to those equipped with thermostatic water temperature regulation, both for heating and for sanitary production, up to systems that support electronic controls for best management of high and low temperature heating as well as sanitary water production“.

Balancing systems: Giacomini's solutions

Balancing is another very important aspect and is not to be underestimated, why?

“Balancing is fundamental to guarantee the correct distribution of the flow rates to the real estate units, it allows the regulators to operate effectively and prevents operational problems. Moreover, there is an economic advantage, because the generators, whether they are boilers or heat pumps, can work at their maximum performance and minimize energy consumption. Fortunately, in recent years the sensitivity towards this important aspect has gradually increased; precisely on the subjects of balancing,  Giacomini's technical library features  a publication that includes methods, construction schemes, instruments and devices necessary to achieve this balancing in the different types of systems. For sure I would recommend to read it throughly in order to gain a better understanding of the concepts involved.

What innovative products does the market offer today for plant balancing?

“Today the designer has reliable and safe solutions. Modern systems are designed to be installed quickly and intuitively. Giacomini has developed a range of modules and satellites also thinking about balancing and equipping them with devices for static, dynamic balancing and for the regulation of differential pressure”.

What attention should you pay to the meter systems equipped with static balancing valves?

“The static balancing valves require an accurate commissioning phase, since it is necessary to proceed to the precise control of each accounting module to verify the correctness of the regular flow rates. It's an iterative and time-consuming process”.

Is it possible to speed up these operations?

“In recent years Giacomini has expanded its range of balancing equipment. Today the available devices are made to simplify the work for everyone, from the designer to the commissioner. Those devices are the dynamic balancing valves and valves for the differential pressure regulation. The systems that integrate these products are those that meet most frequently in favor of market operators, with excellent results to the benefit of the final user”.