Charge the fireclay core quickly from PV surplus

TECHNOTHERM TTB-E 7 Duo 34+ is designed to store a substantial amount of heat within a shorter time window. With suitable energy management, it can use PV surplus, off-peak electricity or low dynamic-tariff hours. Its solid fireclay core accumulates energy and continues to release heat after electrical input has stopped.

Who should choose the 7-hour version?

The 7 Duo 34+ charges for approximately 7–8 hours with a 3.44 kW storage input. It suits installations with a shorter block of solar surplus or low-price electricity and an electrical supply capable of supporting the higher instantaneous load. A separate 750 W direct element responds quickly when extra heat is needed outside the storage cycle.

Key benefits

• faster fireclay charging over approximately 7–8 hours,
• uses PV surplus without an electrochemical battery,
• long-lasting radiant and convective heat,
• separate 750 W direct boost,
• electronic thermostat, time programmes and open-window detection,
• fixed-temperature, weekly programme, Boost and Off operating modes,
• Comfort, Eco and Frost Protection levels, adaptive start and keypad lock,
• internet and app control depending on system configuration,
• only 18.5 cm deep, finished in white RAL 9003,
• made in Germany by TECHNOTHERM / LUCHT LHZ.

Technical data

Included

TTB-E 7 Duo 34+ heater, two floor feet, anti-tip mounting hardware and eight packs of fireclay storage blocks according to the supplier specification. The connection cable and any external PV-surplus control equipment are not included.

PV integration

Automatic charging when genuine surplus is available requires compatible PV energy management, a suitably rated switching device and professional electrical installation. The appliance supports separate 24-hour control power and switched 8/14-hour charging power; the final circuit arrangement must be selected by the electrician. Particular attention must be paid to the 3.44 kW instantaneous input.

Installation note: the appliance weighs approximately 162 kg. It must stand on a level load-bearing floor and be secured to the wall against tipping. The fireclay blocks are fitted on site. The manufacturer requires the first charge to be supervised by a qualified electrician. Output and positioning must match the electrical supply, calculated building heat loss and available PV power.