Area of use

The RFA 38/VBB is used in radiators, convectors and towel dryers.
NOTE! Do not use in HVAC systems
The valves can be regulated with a thermostatic head or a M28x1,5 handwheel.


The RFA 38 has a concealed pre-setting function in the stuffing box. Pre-setting of the 2-pipe system can be carried out using an FN2 key or the FV5 pre-setting tool.
The valve is connected to the pipe system using an M22x1.5 connection.
The valve tail has an R1/2” connection to the radiator.

The valve is supplied as a 2-pipe valve but is can be changed into a 1-pipe system. Remove the blue plastic plug from the bypass valve and unscrew the spindle using a 2.5 mm Allen key.The bypass valve is used to balance the flow between the radiator and the bypass.

The valve’s return is closed using a 2.5 mm Allen key and the inlet is closed using the thermostatic head or
the handwheel. The bypass is not closed.

Technical data

Pressure class
PN 10
Max temperature
Min temperature
Brass, O-ring EDPM, stainless steel
Surface tratment
For 2-pipe system
Kv value        Kvs value
0,01-0,5          0,64


Pre-setting FN 2
The valve is equipped with an insert which has concealed pre-setting functionality.
Unscrew the protective cap. Remove the stuffing box with the pin (use the tip of the FN2 pre-setting key).
Insert the pre-setting key with the serrated end in the control sleeve and carefully screw it to the bottom (clockwise).Screw up the number of turns outlined in the diagram.
Refit the stuffing box with the pin.

Pre-setting FV5
Remove the protective cap and the stuffing box as outlined above. Screw the control sleeve to the bottom as outlined above. Remove the pre-setting key and fit the pre-setting tool on top of the insert splines and reinsert the pre-setting key in to the tool. Reset the scale to the index mark. Screw up the control sleeve until the required kv value coincides with the index mark. Refit the stuffing box with the pin.

Order designations

RSK number Article number Designation Description
480 61 37 4045803 RFA 38/VBB Interchangeable 1-2 pipe system
480 63 16 9000266 RFA 38-160 RFA 38 including valve tail 160 mm
480 63 17 9000267 RFA 34-400 RFA 38 including valve tail 400 mm
480 60 26 9000116 NG 1527 Valve tail 27 mm*
480 60 27 9000117 NG 15160 Valve tail 160 mm*
480 63 68 9000320 NG 15400 Valve tail 400 mm*
480 60 28 9000118 NGV 15 Valve tail angle *
  • including M26x1,5 nut