Description
Electric storage heating · 7–8-hour charging window · 750 W boost heater
High heat-storage capacity for a short tariff or solar charging window
TECHNOTHERM TTB-E 7 Duo 26+ is a high-capacity, fan-assisted electric storage heater for medium-to-large, regularly used living and working rooms. Three 850 W storage elements charge six heat-storage brick packs. A complete nominal charge stores 20.4 kWh of heat for controlled release later, while a separate 750 W boost heater provides immediate additional warmth when the stored heat alone is not enough.
The 7 Duo version is designed for projects where the low-price tariff, controlled supply or planned photovoltaic charging period is concentrated into approximately 7–8 hours. It stores the same nominal amount of heat as the corresponding 14 Duo 26+ model, but uses a higher charging input to complete the charge in roughly half the time. The electrical supply and charging control must therefore be designed for the 2.55 kW storage load.
How it works
Electricity is stored as heat and released under electronic control
During the enabled charging period, the three 850 W storage elements heat the dense ceramic core. The electronic thermostat monitors room temperature, charge level and the active schedule, while adaptive control determines how much heat should be prepared for the next occupied period. The warm cabinet provides radiant heat and a built-in ultra-quiet fan assists controlled distribution into the room. The current catalogue states approximately 10 dB for the fan.
Manual, weekly programme, boost and off modes are available from the TFT control panel. Open-window detection reacts to a rapid temperature drop so heat output is not continued unnecessarily during ventilation. The current catalogue and manual also describe internet and app control; the required interface, service and exact project configuration are confirmed with the order.
Full nominal charge in 7–8 hours
The 2.55 kW storage input is intended for a compact off-peak, controlled-supply or planned photovoltaic charging window.
20.4 kWh nominal heat store
Six brick packs retain a substantial heat reserve for later delivery instead of relying only on immediate electrical heating.
Separate 750 W boost heater
Short-term comfort demand can be covered without waiting for the entire storage core to charge.
Adaptive weekly control
Room sensing, charge indication and programmable temperatures help align charging and heat release with actual occupancy.
Quiet mixed heat delivery
Radiant heat from the cabinet is combined with a very quiet fan that helps distribute warmth through the room.
Slim 18.5 cm cabinet
At 88.5 cm wide, the heater combines 20.4 kWh nominal heat storage with a smaller footprint than the 34+ variant.
Verified technical data
TTB-E 7 Duo 26+ specifications
The model identity and commercial dimensions below follow the supplier-delivered English TECHNOTHERM 2026/27 catalogue. Charging, safety and installation data were checked against the current manufacturer manual MAG-000007, edition 02/26. The manual uses a slightly different cabinet measurement and installed weight; for access and structural planning, use the larger combined envelope and design load shown below until the documentation supplied with the actual production unit is checked.
| Model | TTB-E 7 Duo 26+ |
|---|---|
| SKU / order number | 842526007 |
| Storage charging input | 2.55 kW (3 × 850 W) |
| Boost heater | 750 W |
| Charging window | approximately 7–8 hours |
| Nominal / maximum thermal charge | 20.4 / 23.2 kWh |
| Storage bricks | 6 packs |
| Indicative room area | up to approximately 20 m²; verify by heat-loss calculation |
| Current catalogue dimensions W × H × D | 885 × 715 × 185 mm |
| Current catalogue weight | approximately 124 kg |
| Installation planning envelope | allow up to 885 × 720 × 185 mm and 127 kg according to the current manual |
| Electrical supply | 230 V, 1/N/PE, 50 Hz; fixed connection |
| Protection class | Class I |
| Finish | white, similar to RAL 9003 |
| Control | TFT display, manual mode, weekly programme, adaptive charging, boost mode, open-window detection and app connection |
| Installation | floor-standing on feet with mandatory anti-tip wall fixing |
| Product-family safety standard | EN 60335 |
Choosing between 7 Duo and 14 Duo
Same storage size, different electrical load profile
Choose the 7 Duo 26+ when the building must complete charging in a shorter 7–8-hour window and the electrical installation can supply 2.55 kW to the storage element. Choose the 14 Duo 26+ when the same nominal storage capacity should be charged more gradually over 14–16 hours at approximately 1.44 kW. Neither version is automatically more economical: the correct choice depends on tariff availability, photovoltaic control, heat loss and available connection capacity.
Compare the complete electric storage-heater and heat-retaining radiator range or view the TECHNOTHERM products selected by WodaTherm™.
Sizing and energy planning
Heat loss matters more than a simple floor-area figure
The manual’s approximate 20 m² figure is only an initial guide. WodaTherm™ checks room heat loss, insulation, target temperature, usable charging period, tariff or photovoltaic strategy and the available electrical supply before confirming the model. The storage heater should be treated as a controllable thermal load within the building energy plan.
Installation and delivery
Plan the floor, anti-tip fixing, electrical connection and clearances
The appliance stands on its feet; the rear fixing is required to prevent tipping and does not transfer the full heater weight to the wall. The floor must be flat and capable of carrying the installed load. The manual requires at least 2 cm to the wall, 15 cm below a masonry window sill or 20 cm below a combustible sill, 3 cm between two heaters and 50 cm clear in front of the warm-air outlet. Curtains, furniture and combustible objects must remain outside the prescribed clearances.
A qualified electrician must provide the fixed 230 V connection, protective conductor, all-pole isolation, circuit protection and charging-control wiring. The appliance is supplied without a connection cable. The storage bricks are inserted during assembly, and the first charge must be supervised and checked by a qualified electrician. The heater must not be covered.
In stock. WodaTherm™ confirms carrying access and the delivery date with the order. Electrical installation, building work, special internal carrying and external energy-management equipment are included only when expressly quoted.
Documentation
Installation and operating manual hosted by WodaTherm™
Download the TTB-E Duo installation and operating manual
The manual contains binding safety, mounting, wiring, clearance, first-charge, control and maintenance instructions. The documentation supplied with the actual production unit takes precedence for installation and commissioning.
