GDTS products hot water instantaneous water heater DES 1821 Image

DES 1821.

Solar-compatible continuous-flow heater with 18/21 kW output,
electronic control and LC display.

Getting water hot quickly.

The DES 1821 is a solar-compatible, electronically controlled continuous-flow heater featuring bare-wire heating elements and a switchable rated output of 18/21 kW. Ideal in combination with a solar plant or heat pump (twin-power solar). It incorporates components certified by the German Federal Environmental Agency for contact with water, a new hydraulics concept for less pressure loss, and an LC display indicating the temperature setting. The installation template makes the unit compatible with the predecessor DEE/DES ..02, DEE ..03 series.

  • Twin-power. Rated output switchable 18/21 kW. Suitable for hot water inflow temperatures up to 55 °C.
  • LC-Display. Indicating the set temperature.
  • Slim casing. Just 10 cm deep.
  • Faster flushing-out of air bubbles thanks to new hydraulic concept, resulting in less pressure loss.
  • Ideal combination. With solar plant or heat pump.
  • Very efficient. Energy efficiency class A.

Technical data.

Rated power: 18.0/21.0 kW, solar-compatible


Energy efficiency category* : A


Hot water temperature: up to 60 °C


Net weight: 3.5 kg


Dimensions (W x H x D): 236 x 472 x 99 mm


*Range of energy efficiency category from A+ to F

All series models:

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