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LAMBDA heat pumps are sold through authorized dealers. You can search for an authorized dealer using our dealer locator. If that doesn't work, please feel free to contact us via our contact form or by email.

Despite significantly higher efficiency, LAMBDA heat pumps are priced at roughly the same level as similar competing products. This outstanding value for money stems from the high heat transfer achieved through the 3K process, which has allowed us to keep material costs for air heat exchangers relatively low. Furthermore, our motto is: More machine, less housing. We prefer to invest in high-quality, well-dimensioned refrigeration circuit components rather than in expensive designs. When comparing products, the model designation is often misleading. The model designation of our heat pumps is based on the maximum output at an outdoor temperature of -10°C. For most other heat pump manufacturers, the model designation corresponds to the maximum output at an outdoor temperature of 2°C or 7°C. As a result, our EU13L, for example, is more comparable to “15-series” machines.

Depending on the country or state, there are various subsidies available for LAMBDA heat pumps.
Currently, the installation of heat pumps is heavily subsidized. This applies
in particular to the transition away from oil and gas in existing buildings.

Subsidy agencies in Austria:
sanierungsoffensive.gv.at
Tip: Federal subsidies can be combined with state subsidies—for even greater financial support. Click
here for subsidy opportunities in 2026

Subsidy agencies in Germany:
Bafa

Yes! LAMBDA heat pumps offer a wide range of hydraulic systems and accessories for heat pumps. We also sell hydraulic systems designed specifically for our heat pumps, including buffer tanks, hygiene tanks, hot water tanks, and combination tanks, as well as fresh water systems.

Thanks to their small footprint, LAMBDA heat pumps are among the most space-saving heat pumps on the market. Our EU-L heat pumps are among the most space-saving units in their class on the market. With a footprint of just 0.55 m², there is a suitable spot for them in every garden, and minimum distances to neighboring properties can be more easily maintained. However, at 1.7 m, the units are relatively tall. 

This design also offers technical advantages:

• up to 0.7 m of snow is possible without efficiency losses
• Prevents the formation of a cold air pocket and the associated efficiency losses
• Blockage of the airflow by leaves lying on the ground is prevented

LAMBDA heat pumps are extremely reliable and designed for long-term operation. Our heat pumps are designed to
last for many years. We ensure this through a variety of measures:

• The main components are sourced exclusively from renowned European manufacturers
• Our technical innovation, the 3K process, requires no additional wear parts.
• The 3K process reduces the pressure differential on the compressor -> increasing its service life
• Significantly fewer defrost cycles thanks to the 3K process, which means the compressor is spared a great deal of wear and tear.
• An extremely small refrigerant circuit volume reduces liquid slugging and lubricant dilution at startup. Additionally, continuous oil return to the compressor is ensured at all times.
• The most important (and most expensive) component in the heat pump, the compressor, is operated at all times within the manufacturer’s recommended operating window thanks to sophisticated safety features.

The exact distance between the heat pump and the neighbor’s property depends on the sound power level and the installation location of the heat pump. This is primarily determined by the sound power level of the unit, the zoning of the neighboring property, and the installation conditions. To be sure before installation, use the state-specific noise calculators.

LAMBDA monoblock heat pumps take up less space, are less prone to malfunctions, and require less maintenance. Monoblock heat pumps are compact, self-contained outdoor units that only need to be connected via two heating hoses, a power cable, and a communication cable. In contrast, there are split systems. This means that one part of the unit is located indoors and the other outdoors. In this case, the heat pump is assembled on-site and filled with refrigerant.

We have decided to design our units as monoblock systems. There are several reasons for this:

• The heat pump can be delivered fully tested from the factory.
• No work on the refrigerant circuit is required on-site (a major source of errors).
• The control system and components of the heat pump are perfectly matched to each other. This is not the case with split units, as local conditions vary.
• Lower maintenance
• Monoblock units are generally more affordable
• Simpler installation (no refrigeration technician required for installation)
• Easily replaceable with another unit at the end of its lifecycle. This is not the case with split systems, as the same connecting lines often cannot be used.
• Longer compressor lifespan, as the large refrigerant circuit volume in split systems often leads to liquid hammer, oil return issues, and control fluctuations.
• Split units require the use of synthetic HFC refrigerants, which have a high global warming potential. By 2030, these refrigerants will be phased out of the market due to an EU regulation. Consequently, significant price increases are projected due to the limited production volume of HFC refrigerants.

In theory, water-carrying components of outdoor heat pumps can freeze. In practice, this is highly unlikely. The risk of these components freezing arises when there is no water flow or heating for an extended period and the outdoor temperature drops below -5°C. A sophisticated safety system ensures that freezing is prevented both during normal operation and in the event of a malfunction or a power outage affecting the indoor or outdoor unit. In the event of a simultaneous power outage affecting both the indoor and outdoor units—such as during a blackout—the heat pump’s safety functions do not activate. When connecting the hydraulic lines via the ground (standard configuration), internal tests have shown that thermal circulation occurs even without a circulation pump, preventing the water-carrying components from freezing. In addition, the components are insulated multiple times, which significantly delays cooling. A series of tests was conducted for this purpose; the results can be found in the installation manual.

To be on the safe side, we nevertheless recommend draining the outdoor unit in the event of a power outage lasting several hours when outdoor temperatures are below -5°C. This task can normally be performed by the system owner themselves. Should damage actually occur due to a power outage, this is generally covered by home insurance or the utility provider. An exception to this are planned outages by the utility company, which must be communicated to the homeowner. To reduce the probability of freezing to zero, the use of antifreeze in combination with an intermediate heat exchanger is also possible.

When using utility-controlled shutdowns, it is important to use a "soft utility-controlled shutdown" to ensure a longer service life for the unit. Some energy providers offer discounted electricity rates with the restriction that the heat pump’s operation may be shut down (several times) a day to relieve the strain on the power grid. Please note that a so-called “hard” utility lockout—i.e., a sudden disconnection of the power supply (400V)—negatively impacts the service life of some heat pump components. A so-called “soft” utility lockout is recommended. In this case, a signal is interrupted so that the heat pump can shut down its operation within the time window while complying with all safety regulations.

LAMBDA heat pumps can be combined with a photovoltaic system in several ways. There are several—essentially three—ways to make smart use of excess photovoltaic electricity.

Option 1: Digital enable signal

A simple and straightforward option is to provide a potential-free contact (e.g., from the inverter or an energy management system). Our controller features a standard 24V input capable of processing this signal. In other words, as soon as a surplus (e.g., 2 kW) is detected by the inverter, this is communicated to the heat pump via a digital contact. Furthermore, the setpoint temperatures for the storage tanks and heating circuits (adjustable) are increased, and the heat pump is operated at a fixed electrical power (e.g., 2 kW).

Option 2: Surplus Detection via Smart Meter

Via a smart meter (optional accessory), either the PV output or the surplus power at the service connection can be detected. If a certain threshold value (e.g., 2 kW) is exceeded, the heat pump switches to PV mode. In this case, the setpoint temperatures in the storage tanks and heating circuits are again increased. Unlike Option 1, however, the heat pump also attempts to “regulate” the specified output as effectively as possible by varying the compressor speed. This ensures that as little energy as possible is fed into the grid at the feed-in point, while also minimizing the amount of energy that needs to be drawn from it.

Option 3: Output Setting via Modbus TCP

The output setting for our heat pump can be configured via Modbus TCP. The function is then the same as in option 2. The surplus is usually recorded by an energy management system and can be sent to our heat pump controller via Modbus TCP. Important: The energy management system acts as the Modbus master, and the heat pump controller as the Modbus slave. In other words, the energy management system must actively send the values.

The right location for an air-source heat pump depends on several factors. 

The following factors should be considered when selecting a location for an air-source heat pump: 

• Compliance with safety zones (e.g., no basement shafts or ignition sources within a 1-meter radius)
• Free air circulation (avoidance of niches, obstacles, depressions, and obstructions in front of the heat pump, etc.) to ensure efficiency and reduce noise
• Connection lines to the boiler room should be as short as possible
• Accessibility for servicing
• Noise pollution (compliance with required distances to neighboring properties based on noise calculations, distance from bedroom windows or quiet areas)

Find more details here: General Terms and Conditions and Warranty Terms

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