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Language: EN

Blauberg WKH 125-2

Duct water heaters.
EAN codeEAN4058448032646
  • Description
  • Characteristics

For warming up of supply air in ventilation systems installed in various premises.Suitable for installation in supply or air handling units to warm up the supply air flow.For indoor use only if water serves as a heat carrier. For outdoor application use antifreezing mixture (ethylene glycol solution).Compatible with Ø 100 to 315 mm round air ducts.


Galvanized steel case.Copper pipe manifold. Heat exchange surface made of aluminium plates.Airtight connection with air ducts due to rubber seals.Equipped with a nipple for the system deaeration.Outlet header is equipped with a spigot for installation of an immersion temperature sensor or freezing protection mechanism. Available in two- or four-row tube modifications.Suitable for operation at maximum operating pressure 1.6 MPa (16 bar) and maximum operating temperature +100 °С.  


Fixing to round ducts with clamps.  Any mounting position that ensures the heater deaeration. Install a filter upstream to the heater to protect heating elements against dirt ingress.Install the heater in front or behind the fan. In case of mounting behind the fan ensure a distance of not less than two connecting diameters for air flow stabilization and keep the maximum permissible air temperature inside the fan.Connect the heater on counter-flow basis, otherwise its capacity drops by 5-15 %. All the nomographic charts are rated for counter-flow connection.For correct and safe heater operation an automatic control and protection system is recommended, including the following functions:
– regulation of the heating capacity and temperature of the air heated up;
– filter clogging control by a differential air pressure sensor;
– ventilation system start-up with pre-heated heater;
– use of air dampers fitted with a spring return actuator;
– fan turns off in case of freezing danger for the heater.

Parameter WKH 125-2 Measurement unit
Number of water coil rows 2 -
Casing material galvanized steel -
Air duct for rectangular air ducts -
Connection diameter 125 mm
Weight 4.0 kg

Type Dimensions [mm]
D B H H3 L L1 L2 L3 K
WKH 125-2 124 350 230 150 300 32 43 220 G 3/4”