Vaillant sensoCOMFORT 720f

Product detailed description

VAILLANT sensoCOMFORT 720f - wireless programmable weather-compensated system controller 

• for one direct heating circuit, cooling, ventilation, and hot water preparation
• with the option of cascade boiler control and expansion of control functions using the VR 70, VR 71, and VR 92 modules

Frequently asked questions

• How exactly do I choose the output of a VAILLANT condensing boiler? The basis is the calculated heat loss of the heated building (most reliably taken from the project documentation or an energy certificate). If you don’t have a project, you can estimate roughly 60-100 W per m² of floor area for a typically insulated house built after 2000, or 100-150 W/m² for an older, uninsulated house - the exact figure varies depending on the number of floors, ceiling height, number and quality of windows, and building orientation. A boiler oversized for its output switches on and off more often (so-called cycling), which shortens its lifespan and reduces efficiency; an undersized boiler, on the other hand, cannot sufficiently heat the house on frosty days.
• Why is a condensing boiler more economical than a classic one? A condensing boiler additionally uses the heat hidden in the water vapor produced when burning gas - in a classic boiler this escapes unused through the chimney, while in a condensing boiler it is cooled below the so-called dew point, the vapor condenses, and the released heat is returned to the heating circuit. Thanks to this, condensing boilers achieve an efficiency of approximately 105-110% relative to the calorific value of the gas, compared to the usual 85-92% for classic boilers.
• What type of flue gas exhaust does this boiler need? Most modern condensing boilers are so-called turbo boilers (with a sealed combustion chamber) and require a coaxial (concentric) or separate flue gas exhaust and combustion air supply routed through the perimeter wall or roof - so they do not need a functional chimney. The exact type and maximum length of the exhaust (depending on the 60/100 or 80/125 mm diameter) can be found in the technical documentation for the specific model, or you can consult our customer service.
• What does the ErP energy class shown for the boiler mean? This is a mandatory efficiency label for heating appliances under the EU ErP (Ecodesign) directive, similar to energy labels on refrigerators. Condensing boilers commonly achieve class A, or even higher in combination with room controls (e.g. A+ when using weather-compensated control together with a room thermostat).
• Can I install and connect this boiler myself? No. Connection to the natural gas supply, the electrical network, and the flue gas exhaust is by law reserved exclusively for a person with the appropriate qualification (most often an authorized service technician of the given brand or a certified gas appliance inspector). After installation, the boiler must be commissioned by the manufacturer’s authorized service, which is usually also a condition for the warranty to be valid.
• What about service and warranty? Most manufacturers require a regular annual service inspection by an authorized service provider in order to keep the warranty valid even after its standard expiration (an extended warranty subject to regular servicing is common especially for the Vaillant, Protherm, and Viessmann brands). The exact warranty conditions can be found in the warranty certificate supplied with the boiler.
• What is included in the delivery of this specific product? The exact package contents (the boiler itself, possibly a hot water storage tank, room controls, and other accessories in the case of a set) are stated in the product name and in its technical parameters above on this page.