AB-QM 4.0 Pressure Independent Control Valves (PICV) DN15 - DN32

  • Overview
  • Documents
  • 3D models and drawings
  • Related products
  • Software
  • Warranty
  • News
  • Tender texts

Best-in-class PICV with scaling and clogging resistant design

Danfoss AB-QM was the first of its kind control valve for HVAC heating and cooling applications. AB-QM 4.0 is its next level successor.

The basic principles haven’t changed; It is a control valve with automatic flow limitation and built-in differential pressure controller. The control performance is very accurate and the valve has a – still – unique valve authority of 100%.

But the value the AB-QM 4.0 valves provide has improved a lot. AB-QM 4.0 is the best-in-class PICV currently on the market. The AB-QM 4.0 is available in DN 15 up to DN 32. There are versions with and without test plugs. And versions with internal or external thread connections. The flow capacity increases to a broad range of 20 l/h up to 5,000 l/h and can accurately be measured with the PFM 1000 measuring instrument via Bluetooth on iOS and Android devices.

AB-QM 4.0 is engineered to be the indisputable best PICV on the market. For example it has a scaling & clogging resistant design, PN25 Nominal Pressure, accurate flow measuring and bi-directional filling and flushing. These provide many advantages for designers, installers and end-users.

PICV's increase the energy efficiency of HVAC heating and cooling systems. AB-QM 4.0 is designed for terminal units such as fan-coil units, climate ceilings and chilled beams. Equipped with one of our actuators they accurately control the room temperature and improve the indoor climate. In case it's equipped with our digital actuator, NovoCon S, it enables HVAC 4.0 systems for smart buildings with Internet of Things (IoT) solutions.

Features and benefits

AB-QM 4.0 Product range

The AB-QM 4.0 portfolio offers a wide range of options for all hydronic HVAC applications such as Fan Coil Units, Chilled beams and radiant panels. Here is a quick glance into the many options:

  • DN 15 in Low Flow, Normal Flow and High Flow for design flows from 20- 1200 l/h, with or without test plugs, with internal or external thread
  • DN 20, in Low Flow, Normal Flow and High Flow for design flows from 110 – 1900 l/h, with or without test plugs, with internal or external thread
  • DN 25, in Normal Flow and High Flow for design flows from 230 – 3800 l/h, with test plugs, with internal or external thread
  • DN 32, in normal Flow and High Flow for design flows from 360 – 5000 l/h, with test plugs, with internal or external thread

For every DN size valve there is also an optional to use insulation scale to minimize heat losses from the valves and simplify overall insulation of the heating system.

AB-QM 4.0: We created PICVs - now we redefine the value

New: AB-QM 4.0

Get ready for the next level value of your PICV designs.

AB-QM 4.0 Flexo solution for Fan Coil Units

Increase flexibility and save time during installation, commissioning and servicing of Fan Coil Units (FCUs) with AB-QM 4.0 Flexo. It's a pre-assembled and pressure tested connection set, designed for increased installation flexibility and prefab projects. The set consists of an AB-QM 4.0, two 3-way ball-valves, a strainer, a drain valve and three test plug connections for pressure- or flow measurements. With these the set provides an 8-in-1 solution for hydronic balancing, control, measuring, installation, flushing, filling, draining and servicing of the Fan Coil Units they are installed on.

AB-QM 4.0 Flexo is available in DN15 and DN20. Sets in DN15 contain an AB-QM 4.0 PICV valve with Low Flow, Normal Flow or High Flow, covering design flows from 20 – 1200 l/h. The DN20 sets come with a Normal Flow or High Flow AB-QM 4.0 valve and cover design flows from 110-1900 l/h.

For both DN15 and DN20 sets matching flexible, stainless steel, pipes and EPP insulation are available.

View the 3D model

AB-QM 4.0 CO6 Flexo solution for Radiant Panels

The Danfoss AB-QM 4.0 CO6 Flexo standardized prefab connection set is an innovative solution to make the design, installation, and service on radiant panels or chilled beams in four-pipe heating and cooling change-over systems easier, faster, and more reliable. With a built-in height of just 125 mm, the set will match all requirements. The special ‘click-fit’ connections ensure watertight connections and provide maximum installation flexibility. They also allow fast and easy disassembly and replacement of the AB-QM 4.0 or ChangeOver6 valves. Each individual set is pressure tested after it is assembled.

AB-QM 4.0 CO6 Flexo is available in DN15 Low Flow for design flows between 20-200 l/h, and in DN15 Normal Flow for design flows between 65-650l/h. There are versions with 18mm connections for press-fit, or ½” internal thread. For a fully automated change-over from heating to cooling operation or vice-versa, including remote recommissiong of the design flow setpoint, the set should be equipped with NovoCon® S digital IoT actuator and NovoCon CO6 (Energy) change-over actuator. Alternatively the AB-QM 4.0 can be equipped with AME 110NL(X) modulating actuator for 0(2)-10V or 0(4)-20mA control. In that case the regular CO6 change-over actuator needs to be activated by a dedicated control signal.

The AB-QM 4.0 valve can be equipped with optional EPP insulation to limit the heat losses during heating operation. Customized insulation of the entire set is recommended.

View the 3D model


Promotional and Technical Documents

Type Name Language Valid for Updated Download File type
Data sheet AB-QM 4.0 / AB-QM Pressure Independent Control Valves (PICV) English Multiple 09 May, 2024 3.7 MB .pdf
Brochure AB-QM 4.0 CO6 Flexo product leaflet English Multiple 17 Jun, 2024 980.2 KB .pdf
Data sheet AB-QM 4.0 CO6 Flexo, DN 15, PN 16 English Multiple 26 Jun, 2024 2.4 MB .pdf
Brochure AB-QM 4.0 Flexo Product leaflet English Multiple 06 Apr, 2022 699.5 KB .pdf
Data sheet AB-QM 4.0 Flexo, DN 15-20 English Multiple 06 Jun, 2024 2.2 MB .pdf
Brochure AB-QM 4.0 Product leaflet English Multiple 07 Nov, 2022 680.9 KB .pdf
Brochure AB-QM Actuator Selection Infographic - UK English United Kingdom 15 Jan, 2021 8.6 MB .pdf
Brochure Infographic - Actuator selection for AB-QM PICVs English Multiple 07 Nov, 2022 2.5 MB .pdf
Brochure Infographic AB-QM 4.0 compared to AB-QM English Multiple 07 Nov, 2022 2.3 MB .pdf

Environmental Product Declaration (EPD) Documents

Type Name Language Valid for Updated Download File type
Product Environmental Information - BI EPD ABQM 4.0 DN 15-32 & NovoconS English Multiple 27 Jan, 2023 4.1 MB .pdf
Product Environmental Information - BI EPD ABQM 4.0 DN 15-32 with AME 110 English Multiple 27 Jan, 2023 3.7 MB .pdf
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3D models and drawings

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    Actuators for PICVs

    To take advantage of the combined balancing and control features of Danfoss AB-QM it has to be equipped with actuators controlled by room thermostats or a Building Management System. Danfoss offers a broad range of actuators varying from thermal on-off to digital step motor actuators with bus communication.

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    NovoCon® Digital actuators

    With NovoCon® Danfoss revolutionizes the way hydronic balancing and HVAC control work together. The first of its kind digital HVAC actuators are directly connected with a Building Management System (BMS). This enables System Integrators to design state-of-art, Internet of Things (IoT) solutions.

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    AB-QM 4.0 Prefab solutions

    Increase installation flexibility with AB-QM 4.0 preassembled and pressure tested connection sets for Fan Coil Units and Radiant panels.

Danfoss HVAC 4.0 solutions for smart buildings

This is where the HVAC transformation starts

Find out more about our smart, Building Management System (BMS) connected, HVAC solutions here:


Danfoss set 365 software

Danfoss SET 365 software

Our advanced Danfoss SET 365 3D design software will help you to design and calculate HVAC systems with Danfoss products. A 1-year subscription is FREE available for students, designers and other interested professionals.

AB-QM selection tool

New AB-QM selection tool

You can now easy find the right size and/or pre-setting of your AB-QM valves using our new AB-QM selection tool. Try it out here!


The standard product warranty on AB-QM 4.0 is 2 years. For projects we can agree on an extended warranty period for a full peace of mind. Contact a Danfoss sales representative to find out more.


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Tender texts

The pressure independent balancing and control valve means that the control characteristic is independent from the available pressure. The precise flow control performance of the AB-QM 4.0 with a Danfoss actuator provides increased comfort and superior Total Cost of Ownership. The AB-QM 4.0 ensures and control the required flow on every terminal unit and maintains Hydronic balance in the system.

AB-QM 4.0 has following features:

  • Automatic flow limitation function
  • Modulating below 1% of set flow, regardless of the setting
  • Authority of 1 at all settings
  • Able to close against 16 bar of differential pressure
  • Polymer (PPSU) components of differential pressure controller and control valve cone
  • Linear control characteristic
  • Linear setting
  • Scale in percentage of flow
  • Minimum setting is 10%
  • Setting of flow percentage is visible with actuator mounted
  • Control ratio 1:1000
  • Pressure stage PN25
  • All inner brass parts from DZR (CW602N)
  • Available in the range from DN 15 – 32 for design flows from 20 – 5,000 l/h from one supplier
  • Available with external thread acc. ISO 228/1 and internal thread acc. ISO 7/1
  • Available with test plugs for pump optimization and flow measurements (dpcv)
  • Flow measurements accuracy according to BS7350:1990
  • Characteristic can be changed from linear to equal percentage characteristic at all sizes by adjusting actuator settings
  • Filling and flushing is possible in flow and counter-flow direction
  • Starting pressure of 16 kPa for DN 15 – DN 20 LF and NF
  • Starting pressure of 25 kPa for DN 15 – DN 20 NF
  • Starting pressure of 30 kPa for DN 25 – DN 32 HF
  • Starting pressure of 32 kPa for DN 15 – DN 32 HF versions
  • Leakage rate of no visible leakage for DN 15 - DN 32 in combination with recommended actuator (IEC 60534-4:2007 Class IV)