Privacy Policy (GDPR)
Not registered yet? Take advantages of registration:
Products saving in a binding to the projects
Product consultation from our experts - Online
By using this form, you confirm that you have read the site terms of use Terms of use and completely accept the terms of use

VENTS NKD 150-2,0-1 A21 V.2

Duct heater for supply air post-heating with external control.
Connected air duct diameter – 150 mm.
Heater power – 2.0 kW.

  • Description
  • Characteristics
  • Capacity diagram
  • Downloads
  • Dimensions
  • Designation key
  • Compatibility table
  • Electric heater power selection diagram
  • The heater is designed for integration into a ventilation system and joint operation with an air handling unit equipped with a control system used to switch on the heater and control its operation.
  • The heater maintains the supply duct air temperature at a point set by the unit controller.
  • The casing, the junction box and the heater cover are made of galvanized steel with the heating elements in stainless steel.
  • The heater casing is additionally heat-insulated with 20 mm non-flammable mineral wool layer.
  • The heaters are equipped with rubber seals for airtight connection to the air ducts.
  • NKD A21 V.2 duct heaters are equipped with a factory-wired power cable and a control cable, and also have a duct temperature sensor that is connected to the ventilation unit.
  • Temperature control is carried out smoothly by the ventilation unit controller due to the PWM signal in cycles of 10 seconds.
  • Load commutation is carried out by the semiconductor device (triac).
  • The heaters are equipped with overheat thermostats:
    ⏵main overheat protection with automatic reset at +50 °C
    ⏵emergency overheat protection with manual reset at +90 °C
  • The heater design ensures its mounting on the round ducts in any position by means of clamps (included in delivery).
  • The air flow direction shall match the direction of the arrow on the heater casing.
  • In case of horizontal mounting the control box must be installed with the cover upwards.
  • Swivel range from the normal position up to max. 90°.
  • Do not install the control box with the cover downwards.
Parameter NKD 150-2,0-1 A21 V.2
Measurement unit
Minimum air capacity 170 m³/h
Current 8.7 A
Power 2000 W
Heating electric reheating -
Duct for round air ducts -
Connection diameter 150 mm
Capacity diagram
Capacity diagram
  • Selection method:
  • Air flow:
  • Pressure:
Operating point
  • Air flow: --
  • Pressure: ---
Files archieve
Select document type
  • Advertising and printing products
  • Certificates
  • Technical documentation
"NKD A21 V.2" product description 10-2021 (pdf 481.66Kb)
"NKD A21 V.2" user's manual 09-2021 (V249EN-01) (pdf 1.37Mb)
Download high quality image "NKD A21 V.2" (psd 2.25Mb)
Download image "NKD A21 V.2" for your website (png 476.03Kb)
VENTS NKD 150-2,0-1 A21 V.2
Parameter Value Measurement unit
∅D 150 mm
B 189 mm
H 280 mm
L 306 mm
L1 192 mm
Designation key
Designation key
Series Connected air duct diameter [mm] - Heater power [kW] - Phases Options
NKD 125; 150; 160; 200; 250; 315 0.6; 0.8; 1.2; 1.7; 2.0; 3.0 1: single-phase A21 V.2: compatible with A21 automation, without a DB-9M connector
Compatibility table
Compatibility table
Heater model (connected air duct diameter)  
NKD 125 A21 V.2 VUT/VUE VB EC A21
NKD 150 A21 V.2 VUT/VUE VB EC A21
NKD 160 A21 V.2 VUT/VUE VB EC A21
NKD 200 A21 V.2 VUT/VUE VB EC A21
NKD 250 А21 V.2 VUT/VUE VB EC A21
NKD 315 A21 V.2 AirVents with a 315 mm spigot and an A21 automation without a DB-9M connector
Electric heater power selection diagram
Electric heater power selection diagram

The NKD A21 V.2 heater parameters calculation example:

  • It is necessary to select a heater for supply air post-heating to a temperature of +24 °C, provided the temperature downstream of the heat exchanger is +17 °C. Therefore, it is essential to increase temperature by 7 °C. The ventilation system incorporates the VUT 350 VB EC A21 air handling unit. The rated air flow is 400 m³/h. Determine the intersection of the post-heating temperature line (+7 °C) and the rated air flow line (400 m³/h).
  • In this case the 1200 W heater capacity provides necessary post-heating (+7 °C). The heater NKD 160-1,2-1 A21 V.2 with the diameter matching the spigot diameter of the VUT 350 VB EC A21 air handling unit is a suitable model.
Share your opinion

Basic parameter for domestic fan selection