FAQ

Calculating the hot water demand for any given application is usually done by adding the quantities of water consumed simultaneously (at a given hot water - cold water temperature differential, typically 30 or 35 °, e.g. cold water temperature = 10°C and hot water consumption temperature = 40 or 45°C). The critical demand is generally known as the peak flow, which means the demand that occurs during the first 10 minutes. It is also common to check the peak demand over the first hour (flow 60’) and the continuous demand (per hour). Based on its extensive experience in hot water generation, ACV conducts laboratory analyses to determine the hot water capacities of all of its products and lists their performance ratings at 10’, 60’ and continuous flow.

For example, a standard shower is generally considered to have a flow rate of 8 to 10 L per minute and takes an average of 10 minutes, which represents a hot water demand of 80 to 100 L during the first 10 minutes. It is also generally assumed that the system must be able to fill a bathtub (with a volume of around 150 L) within 10 minutes, which represents a demand of 150 L in 10 minutes. The sum of these demands gives the total peak demand.

By comparing this value to the performance data of ACV systems, you can get an idea of the type of product you need to meet your requirements. Your installer will be able to advise you about the most suitable solution taking into consideration the specific conditions relative to your installation.

For tertiary applications, ACV had developed Archimedes, a sophisticated program designed to calculate hot water demand that takes the specific aspects of each application into account along with a demand simultaneity factor (see “Archimedes

Also known as a « sealed boiler », the balanced flue boiler enables you to operate without a chimney, either in a residence with no chimney (new construction) or in one with a decommissioned chimney (renovation). Piping for flue gas discharge and fresh air intake comprises either a double concentric pipe of about 12 cm in diameter (for the most common residential boilers) or two separate pipes (one for fresh air, the other for combustion gases). The external connection to the balanced flue is either on an exterior wall or through the roof. ACV offers a number of balanced flue boiler models, both gas-fired (fitted with pre-mix burners) and fuel oil-fired (fitted with transparent flame fuel oil burners). ACV balanced flue boilers are approved from 6 to 240 kW (depending on the country).

• Have maintenance performed on your boiler regularly (once per year) to ensure that it always operates at its maximum efficiency.
• Be sure that your home is well insulated (double glazing, air-tight joints along door and window jambs, etc). If this is not the case, investing in better insulation can yield significant savings.
• Close curtains and shutters at night. Windows are often the main cause of heat loss in a home.
• When airing out your home, do not leave the windows open too long (5 to 10 minutes at most). Close the thermostatic valves in the rooms that you are airing out.
• Maintain an appropriate ambient temperature in your home. In general, the temperature should average about 20°C in living room areas, 16 or  17°C in the bedrooms (adequate for all but young children to sleep comfortably) and about 18°C in the kitchen (given the fact that there are other sources of heat). Bathrooms can be maintained at about 22°C. A high quality control system (individually programmable according to time of day and by area within the home) can help you save significant amounts of energy.
• Replace your old heating installation with an up-to-date model. The latest generation of condensing boilers now achieves overall annual efficiencies on the order of 95% versus levels often below 70% for older boilers (15 years old or more).

Yes. ACV offers various water heater models  from 100 to 600 L with an electric heating element (standard or optional) as an alternative heat source. On ACV water heaters, the electric heating element is always located in the primary circuit (on the heating side). The essential advantage of this approach is that it avoids the problems associated with the formation of scale deposits on the heating element (loss of efficiency, bacterial growth in the lime scale). As these heating elements must always remain immersed in water, it is essential that the primary circuit remains filled with water.

In cases where a water heater is not to be connected to a boiler, you must nonetheless include appropriate operating and safety components for the boiler installation itself (safety valve, expansion vessel, fill set). Your installer will be able to advise you accordingly.

It is best to refer to local regulations currently in force, which can vary from country to country. With regard to fuel oil-fired boilers in Belgium, the Royal Ordinance dated January 6, 1978 requires chimney cleaning, maintenance and adjustment of the installation each calendar year (a maximum of 18 months between two service interventions). These services must be performed by a certified company. The certified company prepares a document relative to each service intervention, which you must retain for at least 2 years.

There are no legal requirements in Belgium relative to the maintenance of gas-fired boilers. Nonetheless, it is recommended to have your installation checked annually, if only to assure yourself that  all components are functioning properly and to avoid unnecessarily high gas consumption.

Thanks to the Tank-in-Tank technology, ACV boilers and water heaters normally do not need to be descaled. Each DHW draw-off creates a brief underpressure in the  stainless steel inner  tank (at the moment that the draw-off tap is opened), followed by a slight overpressure (upon closure of the draw-off tap). As the  inner tank is free to move, its walls expand and contract very slightly under the influence of these pressure changes and prevent the formation of lime scale on the exchanger surface: thorough testing and the testimony of numerous users in regions with calcium-laden water confirm that ACV Tank-in-Tank water heaters are truly effective in preventing the formation of lime scale deposits as opposed to traditional coil systems that necessitate frequent descaling. Thanks to this self-descaling feature, the heat transfer efficiency of our water heaters and their hot water output remain high throughout the service life of the installation.

In some regions with extremely hard water and under certain operating conditions, however, a limited quantity of lime scale deposits may occur. In such cases, we recommend that you contact a company that specialises in descaling boilers.