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Blauberg S21 Plug-In Thyristor Frost Protection Electric Pre-Heater Battery for MVHR Units

Order before 3pm for next-day UK delivery.
As low as £280.03 £233.36
 In stock
  • Range of electric plug-in heaters specifically designed to work with Blauberg heat recovery units.
  • Supplied in 125, 150 and 200mm circular duct connection sizes.
  • 0.6 Kw, 1.2 kw & 1.7 Kw thyristor controlled electric pre-heater options.
  • Supplied with power cable & 2.5m control cable to heat recovery unit.


Heat exchanger freeze protection by means of preheating of the intake air. Maintains the duct air temperature at a point that prevents the heat exchanger freezing. Compatible with Ø 125 up to 200 mm air ducts.


Equipped with a power cable. The signal cable for connection to the controller of the air handling unit. Equipped with thyristor control from the heat recovery unit. Regulation is carried out via switching-on and switching-off the full load. Load commutation is carried out by the semiconductor device (triac). The switching unit has no wearing mechanical elements. Equipped with overheat thermostats: main protection with automatic restart at +50 °С; emergency protection with manual restart at +90 °С.


The casing is internally filled with 20 mm layer of non-flammable mineral wool. The casing and the junction box are made of galvanized steel. Heating elements are made of stainless steel. Airtight connection to air ducts due to rubber seals.


Fixation to round air ducts by means of clamps (included in the delivery). In case of horizontal mounting position the control box cover must be directed upwards only. Permitted deviation up to 90°. The control box cover may not be positioned downwards!

Technical details
Electrical Supply1 Phase 220/250 50/60Hz
Control OptionsPre Heater
Tax ClassTaxable Goods
Blauberg S21 Plug-In Frost Protection Thyristor Controlles Electric Pre-Heater Battery for MVHR Units