Hybrid heating in apartment buildings: heat pumps and gas for more efficiency
In Schwabach, the St. Gundekar plant relies on a future-proof hybrid solution from Hoval: six heat pumps and modern gas condensing technology ensure efficiency and security of supply in three renovated apartment buildings.
- Apartment building
- Renovation
- Heat Pump
Efficient heating solution during ongoing operations
The project encompassed three buildings, each with 32 residential units and a total heated area exceeding 8,000 m². Two of the buildings had already been modernized a few years earlier, while the third underwent complete renovation alongside the current heating system upgrade. In addition to refurbishing the heating and domestic hot water systems, this work included bathroom renovations, new electrical installations, a PV system, an external thermal insulation composite system, and demand-controlled exhaust air systems.
The goal was to provide a sustainable, efficient, and future-proof heating solution for the entire property. "The renovation work was carried out while the buildings were occupied. This made it all the more important to ensure a continuous hot water supply and to enable rapid installation of the systems," said Jens Friedrich, a planning consultant at Hoval.
Zukunftssicher mit Hybridtechnik Future-proof with hybrid technology
Thanks to intelligent diverter valves, hybrid control, and visualization via the Hoval Supervisor Cloud, operation can be optimized and adjusted to current demand at any time. "Remote monitoring is a real advantage, especially for hybrid systems with multiple heat pumps: it allows us to fine-tune the system and ensure efficient operation at all times," emphasizes Friedrich.
1 / 8HODE multi-family house outdoor unit air-water heat pump
2 / 8HODE Multi-Family Apartment Building Outdoor Unit Heat Pump_Technology
3 / 8HODE technical room_heat pump
4 / 8HODE Apartment Building Utility Room_Heat Pump_Utility Room
5 / 8HODE Apartment Building Utility Room_Interior_02
6 / 8HODE-Apartment Building-Utility Room_Interior
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8 / 8HODE air-water heat pump interior
Hoval stands out with technical highlights and system advantages
The decision to choose Hoval was a deliberate one: "For complex hybrid systems, Hoval offers all components from a single source, including sophisticated control technology, high product quality, and comprehensive consulting," explains the planning firm SOLIDPLAN. The Hoval solution was integrated during the early planning phase and impressed with flexible, cross-trade support.
Martin Meier of Fritz Meier Haustechnik echoes this sentiment: "Working with Hoval was excellent. We were particularly impressed by the prompt, expert support provided at every stage of the project—from planning through to commissioning."
A technical detail with a major impact: the UltraGas (125) unit used in the project contains no aluminum components on the water-carrying side. This eliminates the need for system separation, making integration into the heating system significantly simpler and more efficient.
Ready for regular operation
The gas boiler system has been in operation since the summer of 2025. The heat pumps were commissioned as scheduled at the end of November 2025. Initial data from winter operations in 2025/2026 is now available and confirms the system's expected performance.
Jens Friedrich draws a positive conclusion:
With this system, we have created the foundation for an efficient, scalable, and future-proof building supply system.