In brief
Sometimes you can keep your existing central heating boiler when adding a hybrid heat pump. That depends on the boiler, the chosen heat pump and their arrangement. Let the combination be explicitly assessed; a working boiler is not automatically a confirmation that each heat pump connects to it. Also identify who assesses the existing boiler and who makes any adjustments to it.
This explanation is part of air conditioning & heat pumps.
What data are required to view compatibility?
Deliver brand, full type, estimated placement date and available boiler and thermostat documentation. An overview photo helps, but do not open an appliance to look for hidden information. Vaillant, for example, describes hybrid combinations where the control varies according to the existing boiler. That is not a universal guarantee for all brands. Ask which link is provided for your concrete combination and which functions are maintained or changed in the new system.
Who decides when the kettle's gonna jump in?
In Vaillant's hybrid explanation, heat demand, outdoor temperature and set energy prices are included in the choice of the heat source. Ask what logic the system offered really uses. Do you have to update rates, does that happen differently or is that function not present? Let's also explain what you serve every day. Two heat sources with unclear agreements are not yet an understandable system; therefore ask for an explanation of normal operation and user settings.
What's the kettle gonna do?
Ask separately for space heating and domestic hot water. Let it be named when the boiler remains necessary and whether existing pipes, thermostats or heating zones are adjusted. Note known malfunctions or comfort problems prior to assessment. An extra heat pump is not a promise that an existing defect will disappear. Ask what needs to be solved first, what falls within the new installation command and what belongs to the batch that follows your boiler today.
Is hybrid a final solution or an intermediate step?
Tell me if you want to keep the boiler for a long time or to heat it completely electric later. Please include your planned insulation and renovation work. Ask which parts will remain usable and which later assessment is still needed. The entry "Popular preparation' should be provided with a concrete explanation. In addition, allow the costs of both retained systems and any separate maintenance arrangements to be visible without assuming that one quote takes over all follow-up.
Send the boiler data to Wattra
Deliver your municipality, existing device data, current maintenance batch and your reason to consider hybrid. Add familiar consumption data and upcoming renovations. Ask for a proposal describing heat pump placement, coupling, regulation and any work by other parties separately. Wattra discusses hybrid installations from Sint-Niklaas throughout Flanders. The application does not yet set you down on boiler retention; first it becomes clear which combination and division of tasks should be assessed for your project.
Sources & further reading
Official background to the technical explanation. Consulted on 18 September 2026. A manufacturer's source doesn't confirm that we supply that brand.
General decision guidance, not a technical inspection report or a personal return calculation. Your installation or garden requires a separate assessment.
View the related service