Heat pumps are being promoted as a climate‑friendly alternative to fossil‑fuel heating, yet consumers risk costly mistakes when they purchase and install them.
Record sales underline a turning point
According to the Bundesverband Wärmepumpe (BWP), 2025 saw a record 299,000 heating heat pumps sold nationwide – a 55 percent increase over 2024. At the same time, demand for oil and gas heating is falling.
Dr. Jan Ossenbrink, CEO of Vamo, notes that heat pumps now hold a market share of roughly 40 percent in existing buildings, overtaking gas boilers as the best‑selling heating system.
Not every unit fits every home
In an interview with Fr.de, Ossenbrink warns that “the biggest errors often occur during planning, installation and system setting.” He adds that around 80 percent of heating installers lack experience with heat pumps.
He advises homeowners to seek thorough advice and work with a skilled installer to ensure the chosen device matches the building’s consumption, structure and location.
Five common pitfalls to avoid
Ossenbrink highlights five mistakes that frequently lead to expensive problems:
- Incorrectly filed subsidy applications: “Applications must be submitted in advance and cannot be added later,” he explains. Professional providers often offer a subsidy‑service to streamline the process.
- Choosing overly cheap heat pumps: “Low‑cost units often cut corners on components, leading to reduced efficiency after a few years and higher operating costs.”
- Poor placement of the unit: “Each model specifies an optimal location. Before installation, consider factors such as airflow, minimum distances and noise levels.”
- Mismatch between pump size and household demand: “A pump that’s too large will cycle on and off, although an undersized unit runs at full load constantly, causing wear and higher electricity use.”
- Improper system setting: “Only a properly and individually adjusted pump works efficiently. Otherwise, even the best‑sized unit adds no value.”
Installation is feasible for most buildings
Ossenbrink reports that about 80 percent of existing buildings can be converted to heat‑pump heating without major modifications. An additional roughly 10 percent require only the replacement of a few radiators.
In rare cases, installing a heat pump may not be economically sensible, but such exceptions are limited.
Frequently Asked Questions
How many heat pumps were sold in Germany in 2025?
According to the BWP, 299,000 heat‑pump units were sold in 2025.
What proportion of existing buildings can be retrofitted with a heat pump?
Roughly 80 percent of existing buildings can be equipped with a heat pump without additional adjustments, and about another 10 percent need only minor radiator replacements.
What are the most common mistakes when buying a heat pump?
The five most frequent errors are: failing to file subsidy applications correctly, opting for overly cheap units, improper placement, mismatching pump size to household demand, and incorrect system settings.
What steps will you take to avoid these pitfalls when considering a heat pump?
