• Provides a constant supply of domestic hot water (steam or water heated)
  • High heat transfer coefficient in accordance with demand of 3-75 l/min domestic hot water production
  • Extra small installation size, takes up little space - 100 mm diameter
  • Maximum allowable operating pressure on both sides 16 bar, maximum temperature 150 °C
  • Parts having contact with fluid (water) are made of stainless steel
  • Durable, welded structure, 0,8 mm polished, stainless steel coiled plate
  • Can be easily unloaded without using adhesive; by use of aggressive medium Teflon coating can be also inserted
  • Rubber tubing made of silicone and Teflon
  • Connection nozzle types: with threads or flanges

FÉG-Spirec KN heat exchangers have an extra small installation size, high strength and durability. The cylindrical coiled heat exchanger with a diameter of 100 mm prepares domestic hot water. It can be further used for floor and swimming pool heating or in solar thermal applications.
Water flows through helical coils in turbulent condition (see figure). One of the heating medium (A) flows through a curved pipe, the other one (B) will pass across.

Maximum heat transfer factor ranges between 3-6 kW/m2K. This implies a better heat transfer; at a proper continuous water flow speed of >1m/sec no scale formation will be occurred in the exchanger.

Operating scheme of heat exchanger
A. Shell side
B. Coil side

KNV- series
Based on the KN series KNV heat exchangers have very good features. Entire system is assembled with corrosion resistant elements, designed in accordance to technical requirements of building regulations.
KNV heat exchangers are smaller than KN exchangers. Demand for small space and thin plate structure results a very good heat transfer coefficient; it can be used under different pressure conditions. Extra small size and hydraulic characteristics makes FÉG Spirec KNV heat exchangers optimal for serving modern heating appliances.
Incoming fluid enters the heat exchanger on the shell side. Then the heat exchanger completely separates the primary and secondary sides; that’s why KNV heat exchanger is ideal for a combined heating system.
KNV heat exchangers have been installed exclusively in FÉG Cirkonova boilers so far.

  • Extra small installation size, takes up little space
  • Excellent heat transfer coefficient
  • Suitable for exchanging a very small amount of water as well
  • Wide range of use: domestic hot water production, separation of heating system, operating floor heating, cooling processes
  • Parts having contact with fluid (water) made of 0,5 mm corrosion resistant steel
  • AWI-welding (not soft soldering or lead lock)
  • Silicon (basic series) or Teflon (optional) divide plumbing
  • Operating temperature -50°C to150°C
  • Maximum operating pressure: 10 bar, test pressure: 15 bar
  • Connection nozzle types: with threads or flanges