Thermann 21R Continuous Flow 50C Natural Gas

Thermann 17R Continuous Flow 50C Natural Gas

Thermann 21R Continuous Flow 50C Natural Gas

The Thermann 21R Continuous Flow 50°C Natural Gas system delivers energy-efficient, instantaneous hot water tailored for modern homes. With a high 6.1-star energy rating and Japanese-manufactured internal components, this system ensures consistent hot water supply at a pre-set safe temperature of 50°C, making it ideal for families or households requiring safe, reliable, and efficient performance. Its compact wall-mounted design allows for seamless outdoor installation, and it includes advanced frost protection features.

FEATURES:

Heating Method:
Gas burner with direct electronic ignition

Hot Water Supply:
Continuous flow – instantaneous hot water on demand

Recovery Time:
Instantaneous; no storage tank, heats water as needed

Installation Location:
Outdoor wall-mounted only

Water Pressure:

  • Minimum: 200 kPa
  • Maximum: 1000 kPa

Energy Efficiency:
6.1 Star energy rating

Operating Costs:
Reduced due to high thermal efficiency and low standby loss; safe 50°C delivery minimizes unnecessary reheating

Best for:

  • Homes with 2–3 bathrooms
  • Households needing continuous hot water
  • Locations requiring pre-set safe temperature output (50°C)

Number of Bathrooms and People (Capacity):

  • Suitable for 2–3 outlets
  • Delivers 21 L/min at 25°C rise, ideal for 2 bathrooms and up to 4 people

Additional features:

  • 50°C factory preset temperature for user safety
  • Built-in freeze protection
  • Optional temperature controllers available
  • Includes water inlet filter for clean operation
  • Japanese-manufactured internal components for reliability
  • Suitable for installation with water-efficient tapware
 

Specifications

Hot Water Delivery: 21L/min @ 25°C rise
Gas Consumption: 159 MJ/h (Natural Gas)
Weight (Empty) 15 kg
Height 520 mm
Width 350 mm
Depth 170 mm

Warranties

Manufacturers Tank Warranty (Domestic) 12 years on the heat exchanger
Manufacturers Parts & Labour Warranty (Domestic) 3 Years

Technical Specifications

Powerpoint Required: Yes – 230–240V AC, 50Hz (max output current: 0.44 A)
Gas Connection: R3/4" (20mm)
Hot Water Connection: R3/4" (20mm)
Relief Valve Pressure: 1620 kPa
Minimum Flow Rate for Ignition: 2.5 L/min
Test Point Pressure: 0.62 kPa
Water Inlet Connection: R 3/4" (20 mm)
Freeze Prevention Heater Power: : 129W
Input Current: 0.44 A
Test Point Pressure (NG): 0.62 kPa