The holiday program of a Viessmann heating system

Viessmann boilers come with a wide range of factory default settings. They enhance operating convenience, enabling any changes to be performed on the heat generator in just a few simple steps. The default settings also help to save energy and thus reduce heating costs. In addition to the heating curve, there are also various time programs. These include an economy mode and a holiday program.

The holiday program can only be accessed as a "time program" via the heating controller. Those who live in rented accommodation or otherwise do not have access to the heat generator cannot make any changes to the holiday program. 

The holiday program in detail

System owners, on the other hand, can use the program to enter arrival and departure dates for each individual heating circuit. This means that they can actively influence the heating characteristics of the heat generator. The holiday program of a Viessmann heating system specifically affects central heating, DHW heating, heating output and energy consumption:

Central heating:

• For heating circuits in the "Heating and DHW" operating program, the holiday program heats the rooms to the set reduced room temperature.
• For heating circuits in the "DHW only" operating program, there is no room heating. However, frost protection for the boiler and the DHW cylinder is active.

DHW heating:

• If holiday mode is activated for all heating circuits, there is no DHW heating. However, frost protection for the DHW cylinder is active.

Please note: In the factory settings, the holiday program starts at 00:00 h on the day following your departure and ends at 00:00 h on the day of your return. This means that the set time program is active on the day of departure and return. The time can also be set individually on some models. To end the program manually, please follow the instructions.

The holiday program reduces the heating output

When the holiday program is activated, the system maintains a lower set room temperature. It only heats to a previously set reduced room temperature. This temperature should not fall below 16 degrees Celsius, otherwise there is an increased risk of mould forming. You can read up in our guide to preventing mould on how you can minimise this risk.

The holiday program helps to save energy

The holiday program feature of a Viessmann heating system gives system owners the opportunity to save energy during their absence by only heating as much as is necessary. Contrary to what the name suggests, the program is not intended solely for use during "multi-week holidays" in the traditional sense. If system owners know they are going to be away – even just for a few days – they can activate the holiday program and so save on heating costs.

How to activate the holiday program

The time program and the associated holiday program feature on all Viessmann boilers with Vitotronic control units (from 1999). However, the navigation route from the main menu to this function can vary depending on the heating system and year of manufacture. The correct procedure is described in the operating instructions provided or alternatively can be found in the service instructions. For a better understanding of the process, the instructions for four different heat generators are shown below. This includes:

• Vitodens 200 W with Vitotronic 200, for weather-compensated operation, year of manufacture 2018
  
• Vitoladens 300 C with Vitotronic 200, year of manufacture 2018
  
• Vitocal 200 S with Vitotronic 200, year of manufacture 2017
• Vitoligno 300 C with Ecotronic, year of manufacture 2017