Heat Meters: Models and Prices

A heat meter measures the heat energy, in kWh, consumed by each apartment or other unit in a central heating or cooling system. This category features heat meters from Novus Digitermo, Minol Zenner, Calmet, CEM, İntegral, Danfoss and Honeywell: DN20–DN40 threaded ultrasonic heat meters for apartments and DN50–DN300 flanged large-diameter heat meters for high-flow systems. Filter the models by size, brand and communication type (wired M-Bus or RF/wM-Bus) to compare prices. Our guide What Is a Heat Meter? explains how heat meters work and how to choose the right size, and How to Read a Heat Meter walks you through the display values. To compare brands side by side, see our Heat Meter Brands Compared guide.

What Is a Heat Meter?

A heat meter measures and records the heat energy consumed by each apartment or other unit in a central heating or cooling system. It is used above all in centrally heated buildings, so that each apartment's consumption can be billed fairly. The meter is typically installed in the return line of the manifold group at the apartment entrance.

In modern central heating systems where each apartment has its own supply and return manifold, consumption is measured with a heat meter; in older systems with multiple vertical risers, a heat cost allocator is fitted to each radiator instead. We explain the difference between the two methods in detail in our article Heat Meter or Heat Cost Allocator?

Note: The heat meters on this page are for building heating and cooling installations; they are not laboratory calorimeters.

How Does a Heat Meter Work?

A heat meter calculates energy from three measured values:

• The volume of water (flow rate) passing through the system
• Flow (supply) temperature
• Return temperature

An electronic calculator unit processes these three values and computes the heat energy consumed by the apartment in kWh (kilowatt-hours). The temperatures are measured by a matched sensor pair (e.g., PT1000). Readings can be taken from the meter's display or monitored remotely via M-Bus or RF (wM-Bus) communication.

Types of Heat Meters: Mechanical and Ultrasonic

Mechanical Heat Meters

Mechanical heat meters measure flow with a mechanical impeller, much like a water meter, while the electronic unit calculates the temperature difference and the energy. They are an economical solution, well suited to standard residential applications (see mechanical heat meters).

Ultrasonic Heat Meters

Ultrasonic heat meters calculate the flow rate by measuring the transit time of sound waves through the water. With no moving mechanical parts, they are not subject to wear, last longer and measure with higher accuracy.

• High measuring accuracy, with stable measurement even at low flow rates
• Low maintenance, as there is no mechanical wear
• Less affected by limescale and sediment than mechanical meters
• Long battery life

For apartments, see our ultrasonic heat meters (DN20–DN40, threaded); for high-flow systems, see our large-diameter heat meters (DN50–DN300, flanged).

Which Heat Meter Size (DN) Do You Need?

Choose the meter size based on the system's design flow rate, not just the pipe size. The values below are taken from our Calmet PM02 series product pages; body length may vary by brand and model.

DN20 is the most common size in apartments; compare all models in this size in the DN20 heat meters category.

Communication Options: M-Bus, wM-Bus and LoRa

What Is an M-Bus Heat Meter?

M-Bus (Meter-Bus) is an international protocol that lets meters communicate with a central system over a wired connection. A single pair of wires carries both the power supply and the data. Heat meters with M-Bus support are called M-Bus heat meters; they allow central reading and are ideal for large projects. Up to 250 meters can be addressed on one bus (in practice, this depends on the capacity of the M-Bus master).

What Are RF Heat Meters (wM-Bus and LoRa)?

Heat meters with RF (radio frequency) communication transmit their data wirelessly: no cabling is required, which makes remote reading easier in residential complexes and large housing projects. wM-Bus (Wireless M-Bus) modules and LoRa modules, which communicate over long distances with low power consumption, can be ordered as options on the models indicated in the product description. Models listed with a wireless option are in the Wireless (RF) Heat Meters category. For a comparison of the methods, see our article M-Bus, wM-Bus or LoRaWAN: Which Is Right for You?; for converters, see our meter reading equipment category.

How to Install a Heat Meter

Heat meters are used in systems where each apartment is supplied from its own manifold. Key points for installation:

• Depending on the model, the meter is installed in the return or the flow line (most models on our site are designed for the return line); always follow the installation line and position stated in the product description
• Check the flow direction: the arrow on the meter must point in the direction of flow
• A strainer upstream of the meter is recommended; this is even more important for mechanical (impeller) meters
• Fit isolation valves before and after the meter for easy maintenance and removal
• On most models, one temperature sensor comes factory-fitted in the meter body; the other is installed in the opposite line, usually in a ball valve with a sensor port, and then sealed

After installation, service the system regularly and clean the strainers periodically. Installation parts such as sensor adapters are in the heat meter spare parts category.

For step-by-step instructions and an installation table by brand, see our guide Heat Meter Installation and Replacement.

Heat Cost Allocation and Regulations

In many countries, heating costs in centrally heated buildings are allocated on the basis of measured consumption; in the EU, for example, the Energy Efficiency Directive requires individual metering in multi-apartment buildings wherever it is technically feasible and cost-effective. The readings from the heat meters are used to split the costs among the units according to the applicable national rules: typically, part of the cost is divided as a common share and the remainder according to measured consumption. Learn more in our article How Is Heat Cost Allocation Calculated?; for our meter reading and billing service in Türkiye, see Remote Meter Reading and Billing.

Re-verification and Calibration

Heat meters used for billing are usually subject to periodic re-verification, and the intervals are set by national rules. Check your local regulations for periodic re-verification requirements. For meters installed in Türkiye, our Heat Meter Re-verification and Calibration page explains the schedule and procedure. Before buying, we recommend checking the MID approval and accuracy class (e.g., Class 2) in the product description.

What Determines Heat Meter Prices?

• Measuring technology: mechanical or ultrasonic
• Size and connection type: threaded DN20–DN40 or flanged DN50 and above
• Communication: wired M-Bus, RF/wM-Bus or LoRa module
• Application: heating only or combined heating/cooling
• Brand, country of origin and sensor type

Current prices are shown on the product cards; you can sort the list by price and filter it by brand, size and communication type. For bulk purchases, use the Wholesale Order Form on the product pages.

Heat Meter Models by Brand and Size

The tables below list the heat meters on our site by brand and size: each cell links to that product's page with its current price, and each column header links to all models in that size. Prices are set in EUR or USD. Export prices exclude Turkish VAT; import duties and taxes in your country are paid by the buyer.

Apartment heat meters (threaded)

Large-diameter heat meters (flanged)

Benefits of Heat Metering

• Fair and transparent billing
• Energy and cost savings
• Consumption tracking and analysis
• Easy remote reading and management
• Environmental sustainability

Heat Metering Solutions from Novus Energy

novus.tr is the online store of Novus Energy, founded in 2018 in Çekmeköy, Istanbul. It supplies mechanical and ultrasonic heat meters with M-Bus and RF communication options for private and commercial projects. In Türkiye, Novus Energy also provides remote meter reading and billing services as well as heat meter re-verification and calibration. Corporate website: novusenerji.com.tr.

Frequently Asked Questions

What is a heat meter?

A heat meter is a device that measures the heat energy consumed by each apartment or other unit in a central heating or cooling system. By measuring each apartment's consumption in kWh, it makes fair billing possible.

What is the difference between a heat meter and a heat cost allocator?

A heat meter is used in systems where each apartment is supplied from its own manifold, and it measures the energy the apartment consumes directly. A heat cost allocator, by contrast, is fitted to each radiator in systems with multiple vertical risers and produces a relative value that is used to share the costs.

Mechanical or ultrasonic heat meter: which should I choose?

Mechanical heat meters are more economical, while ultrasonic heat meters offer higher accuracy, a longer service life and lower maintenance. The right choice depends on the requirements of your project.

What size heat meter does an apartment need?

DN20 is the most common size in apartments. The correct size is determined by the system's design flow rate; when replacing an existing meter, choose a model with the same size, body length (L) and connection size.

What determines heat meter prices?

Prices depend on the measuring technology (mechanical or ultrasonic), the size, the communication type (M-Bus, RF/wM-Bus, LoRa), the brand and the technical specifications. Current prices are shown on our product pages.

Do heat meter prices include VAT?

No. Export prices exclude Turkish VAT, and import duties and taxes in your country are paid by the buyer. Prices are set in EUR or USD.

Can heat meters be used in cooling systems?

Yes. Heat meters with suitable specifications can be used not only for heating but also in cooling and combined heating/cooling systems.

How often do heat meters need to be re-verified?

It depends on the country: re-verification intervals for heat meters are set by national rules. Check your local regulations for periodic re-verification requirements.