Heating

Heat pumps

This page is for anyone replacing an old heat source, building or renovating a house and considering a heat pump instead of a boiler. We explain the differences between heat pump types, what affects their operation and what to ask an installation company, without being tied to any specific brand.

Types of heat pumps and which house they suit

The most common type is the heat pump. vzduch-voda. It extracts heat from the outdoor air and heats water for radiators, underfloor heating and domestic hot water. It is suitable for virtually any house with a water-based heating system; the main limitation is usually space for the outdoor unit and any requirements regarding setback distance from neighbouring land.

Vzduch-vzduch It is essentially an air conditioner with a heating function. It heats the room air directly, without water in the system. It warms up quickly but typically does not heat a house evenly and is not suitable as the sole heat source where hot water is also required. It works well as a supplement or in well-insulated flats and smaller houses with an open-plan layout.

Ground-water (ground collector or borehole) and voda-voda They extract heat from the ground or groundwater, whose temperature remains more stable throughout the year than air temperature. Therefore, their output does not drop as much in freezing conditions as with air-source variants, but installation requires land for a collector or borehole, a geological survey and permits.

Typ	Zdroj tepla	For which house	Performance in freezing conditions
Vzduch-voda	outdoor air	a detached house or a flat with a water-based system	drops, addressed by the bivalent point
Vzduch-vzduch	outdoor air	flat, smaller insulated house, supplement	drops, no water in the system
Ground-water / water-water	ground collector, borehole, groundwater	a detached house with ample grounds	more stable throughout winter

How the heat pump works and why the heating water temperature matters

A heat pump does not generate heat directly but transfers it from the surroundings using a refrigeration circuit, much like a refrigerator, only in reverse. The ratio between electricity supplied and heat obtained (heating factor) increases as the required temperature of the heating water decreases. Therefore, heat pumps work well with underfloor heating or oversized radiators, but less effectively with old small radiators designed for high temperatures.

What affects the price

The price is determined not only by the unit's capacity but also by the type of heat pump, the need for earthworks in ground-water variants, possible modifications to the heating system (radiator replacement, new distribution), the condition of the electrical installation and circuit breakers, and whether an additional bivalent source is required. An indicative price range including installation can be found on page with price guides - The exact amount for your building will be determined by an on-site survey.

Subsidies

Replacing an environmentally unfriendly heat source with a heat pump is one of the supported items in the programme. Nová zelená úsporámConditions, the scope of eligible applicants and the submission procedure change over time; therefore, always verify the current status directly on the programme's website. In Prague, a separate programme run by the capital city is also available. Clean Energy Prague, which also covers air-to-air heat pumps, outside the capital you will usually not find a similar local programme.

What to watch out for when choosing an installation company

A solid company will calculate the building's heat loss, not just estimate it based on floor area, and can explain why a specific output and heat pump type are recommended. Ask about their experience with your particular heating system (radiators vs underfloor heating), whether they also carry out any necessary modifications to the heating system, what the warranty covers for both equipment and installation, and who provides servicing after installation. References from older projects in comparable types of buildings are a better indicator than general slogans.

Operation and maintenance

The outdoor unit must be kept accessible (snow, leaves, dust on the heat exchanger) and its pressure and operation checked regularly. For equipment containing a certain amount of refrigerant, the law mandates regular inspection of the cooling circuit's tightness: the company will inform you of this obligation during installation. An annual service inspection helps detect minor issues before they affect efficiency.

Common mistakes

The most common problems are an undersized or unnecessarily oversized capacity selected without a heat loss calculation, unsuitable placement of the outdoor unit disregarding noise impact on neighbours or airflow space, unresolved bivalence point in air-only variants, and connection to an old heating system without assessing whether it can accommodate lower heating water temperatures.

Frequently Asked Questions

Is an air-to-air heat pump worth installing in an old, uninsulated building?

It mainly depends on the building's heat loss and the temperature of heating water required by the existing heating system. The lower the heat loss and the lower the design temperature (typically large radiators or underfloor heating), the more efficiently the heat pump operates. In an uninsulated house with small radiators designed for high water temperatures, efficiency is usually lower, and it often pays to combine replacing the heat source with upgrading the heating system, possibly including partial insulation.

How noisy is a heat pump?

The outdoor unit has its own sound power level, which is specified by the manufacturer in the technical data sheet. When installing near bedroom windows or a neighbour's property boundary, it is advisable to address the unit's placement, distance from the property line, and potentially a quieter night mode during the design phase, not after installation.

Do I need building permission for a heat pump?

For an outdoor air-to-water unit on the façade or on the plot, a notification is usually sufficient, but the exact requirement is determined by the local building authority and the specific location. For a ground collector or borehole for the water-to-ground variant, regulations are stricter; for a borehole, cooperation with the mining authority is also required. It is always sensible to verify requirements with the installation company and the building authority in advance.

Can I combine a heat pump with my existing gas boiler?

Yes, this is a so-called hybrid connection. The heat pump covers the basic heating load for most of the heating season, and the boiler only kicks in during peak frost periods when the heat pump alone would be insufficient. This also addresses the so-called bivalence point, i.e., the outdoor temperature below which the heat pump's output no longer meets the building's demand.

How long does a heat pump last?

Manufacturers usually state a lifespan of fifteen years or more, with the compressor being the most vulnerable component. Actual longevity depends on installation quality, sizing and regular maintenance, which is why it pays to arrange for the installer's service support from the start.