The Stiebel Eltron DEM 6 Set (product no. 236463) is a 5.7 kW mini instantaneous water heater offering the highest output in the DEM Set family. It delivers a steady, electronically controlled hot water supply to a hand washbasin and — at inlet water temperatures above 20 °C — is also suitable for shower use, giving it broader application potential than the lower-output DEM 3 variant. The unit features full electronic closed-loop temperature control via an outlet sensor, ensuring the water reaches the set temperature without cold-blending at the tap. The hardwired connection requires a dedicated 25 A RCD-protected circuit and installation by a qualified electrician. Equally suited to oversink and undersink mounting and compatible with both pressurised and non-pressurised taps, the DEM 6 Set is the professional choice for cloakrooms, commercial washrooms, beauty salons, and any single draw-off point demanding maximum instantaneous hot water performance from a compact wall-mounted unit.
5.7 kWRated Output
24.7 ARated Current
25 ACircuit Fuse
30–50 °CTemp. Range
IP25Protection Rating
1.70 kgWeight
Installer Notice — Hardwired Connection Required:
The DEM 6 Set does not include a plug and must be permanently hardwired via a dedicated 25 A double-pole isolator with a minimum 3 mm contact separation, protected by a 25 A RCD circuit. The supply cable must be 4 mm² cross-section minimum. Installation must be carried out by a qualified electrician in accordance with BS 7671 and Part P of the Building Regulations.
Installer Notice — Water Resistivity:
This appliance uses a bare wire heating element. The electrical resistivity of the cold-water supply must be ≥ 1000 Ω·cm (conductivity ≤ 1000 µS/cm) at inlet temperatures up to 25 °C, or ≥ 1300 Ω·cm (conductivity ≤ 770 µS/cm) above 25 °C. Verify local water quality before installation. Do not install on demineralised or RO water supplies without specialist advice.
Shower Use — Inlet Temperature Condition:
The DEM 6 Set is suitable for shower use only when the cold-water inlet temperature exceeds 20 °C. Below this threshold it is rated for washbasin use only. Where the unit supplies a shower, the qualified contractor must confirm that the internal temperature limit is set appropriately and that the outlet cannot exceed 43 °C without user awareness.
Anti-Scalding Temperature Lock:
The internal permanent temperature limit provides child-safe, fixed anti-scalding protection. If this limit requires adjustment, it must be performed by a qualified contractor — it is not user-accessible. The user-adjustable range is 30–50 °C.
Highest Output in the DEM Set Range:
At 5.7 kW (230 V), the DEM 6 Set delivers the maximum flow rate and temperature rise of the DEM Set family, making it the preferred choice where mains water temperatures are low or where shower-capable performance is required from a compact under-sink installation.
Key Features
Electronic Closed-Loop Temperature Control
A dedicated outlet temperature sensor feeds continuous data to the onboard control electronics. Output is adjusted in real time so the water exits at exactly the set temperature. No cold-blending is required at the tap, meaning every litre of water drawn is at the correct temperature — eliminating energy waste and delivering consistent comfort.
Shower-Capable Performance
With 5.7 kW available at 230 V and a switch-on flow rate of >2.2 l/min, the DEM 6 Set provides sufficient thermal output to supply a shower head when the cold-water inlet temperature is above 20 °C. This makes it a versatile solution for beach huts, garden rooms, leisure facilities, and commercial washrooms where a second draw-off point may be added.
Bare Wire Heating Element
The maintenance-free bare wire heating system transfers heat directly into the water stream, delivering hot water instantly from the moment the tap opens. The element is rated for both hard and soft water, and its open-wound construction resists scale formation that can shorten the life of conventional sheathed elements.
Anti-Scalding Protection
Dual-layer protection: automatic output matching reduces heating power if inlet temperature rises unexpectedly, while a fixed internal temperature limit (set by a qualified contractor) provides a permanent backstop. Together these protect against scalding regardless of mains temperature fluctuations.
PROFI-RAPID Installation System
The back panel doubles as a precision drill template, with elongated slots to tolerate drill-hole placement errors. Two-point wall fixing is all that is required. Cover and internal assembly detach in a single hand movement for fast access during commissioning and future servicing. External metal G 3/8 A water fittings allow direct tap connection.
Oversink and Undersink in One Unit
Rotating the appliance 180° switches between oversink and undersink configurations without any component changes. Water connections and cable routing are designed to suit either orientation, giving maximum flexibility when working around existing pipework or cabinetry.
Pressurised and Non-Pressurised Tap Compatibility
The integral variable flow-rate limiter and special aerator ensure the DEM 6 Set performs consistently with both open-outlet non-pressurised taps and standard pressurised taps. The aerator delivers an optimised flow pattern at the spout for a comfortable handwashing experience.
LED Diagnostic Traffic Light
A built-in three-LED diagnostic indicator provides at-a-glance fault analysis during commissioning and service visits, enabling rapid identification of electrical, water-flow, and control issues without specialist diagnostic equipment.
Point-of-Use Efficiency
By heating water at the draw-off point and only when the tap is open, the DEM 6 Set eliminates standing heat losses and pipework dead-leg waste. No stored volume is kept hot between uses, so energy consumption tracks actual demand — particularly valuable in applications with intermittent or low-frequency use.
Technical Specification
| Identification |
|---|
| Product Number |
236463 |
| Model |
DEM 6 Set |
| Electrical |
|---|
| Rated Voltage |
230 V (1/N/PE) |
| Rated Output at 230 V |
5.7 kW |
| Rated Output at 200 V |
4.3 kW |
| Rated Output at 220 V |
5.2 kW |
| Rated Output at 240 V |
6.2 kW |
| Rated Current at 230 V |
24.7 A |
| Circuit Fuse (200–230 V) |
25 A |
| Circuit Fuse at 240 V |
32 A |
| Frequency |
50 / 60 Hz |
| Connection |
1/N/PE — hardwired, 4 mm² cable, 25 A DP isolator required |
| Water |
|---|
| Water Connection |
G 3/8 A (external metal fittings) |
| Switch-On Flow Rate |
> 2.2 l/min |
| Water Resistivity ρ₁₅ ≥ (inlet ≤ 25 °C) |
1000 Ω·cm (conductivity ≤ 1000 µS/cm) |
| Water Resistivity ρ₁₅ ≥ (inlet > 25 °C) |
1300 Ω·cm (conductivity ≤ 770 µS/cm) |
| Performance |
|---|
| Outlet Temperature Range |
30–50 °C (user-adjustable) |
| Internal Anti-Scalding Limit |
Fixed — qualified contractor only |
| Control Method |
Electronic closed-loop (outlet sensor) |
| Shower Suitability |
Yes — at inlet temperatures > 20 °C |
| Physical |
|---|
| Height |
143 mm |
| Width |
190 mm |
| Depth |
82 mm |
| Weight |
1.70 kg |
| Colour |
White |
| IP Rating |
IP25 (splash-proof) |
Frequently Asked Questions
Does the DEM 6 Set include a plug?
No. Unlike the DEM 3 Set, the DEM 6 Set must be permanently hardwired. It requires a dedicated 25 A double-pole isolator with a minimum 3 mm contact separation, fed by an RCD-protected circuit. The supply cable must be a minimum of 4 mm² cross-section. Installation must be completed by a qualified electrician in accordance with BS 7671 and Part P.
Can the DEM 6 Set be used to supply a shower?
Yes — with conditions. The DEM 6 Set is rated for shower use when the cold-water inlet temperature exceeds 20 °C. Below this threshold, the available thermal output may be insufficient to reach comfortable shower temperatures at adequate flow. Where shower use is intended, the contractor must confirm inlet water temperatures and ensure the internal anti-scalding limit is correctly set.
Can it be installed above or below the basin?
Yes. The DEM 6 Set supports both oversink and undersink installation using the same unit. Rotating the appliance 180° changes the orientation. The PROFI-RAPID back panel serves as a drill template, and external G 3/8 A water fittings accommodate either configuration without requiring separate parts.
Does the DEM 6 Set work with non-pressurised (open outlet) taps?
Yes. The appliance is compatible with both pressurised taps and non-pressurised open-outlet taps. The included integral flow controller and special aerator optimise water flow pattern for both types and maintain consistent temperature performance across varying mains pressures.
What is the difference between the DEM 3 Set and DEM 6 Set?
The key differences are: (1) Output — DEM 3 Set is 3.5 kW; DEM 6 Set is 5.7 kW. (2) Connection — DEM 3 Set has a standard 13 A plug; DEM 6 Set requires a hardwired 25 A circuit with 4 mm² cable. (3) Shower capability — DEM 6 Set can supply a shower at inlet temperatures above 20 °C; DEM 3 Set is rated for washbasin use only. (4) Switch-on flow rate — DEM 3 Set activates at >1.5 l/min; DEM 6 Set at >2.2 l/min. Both share identical physical dimensions and the same PROFI-RAPID installation system.
Is it suitable for hard water areas?
Yes. The bare wire heating element is inherently resistant to scale build-up and is approved for both hard and soft water areas. There is no anode rod or sacrificial component to maintain. However, the minimum water resistivity specification must be met (≥ 1000 Ω·cm at ≤ 25 °C inlet temperature) — always verify your local water supply before installation.
What maintenance does the DEM 6 Set require?
Routine maintenance is minimal. The bare wire element is maintenance-free. The built-in strainer should be inspected and cleaned periodically — particularly during initial commissioning and after any work on the incoming water supply. If the appliance is drained or de-energised for an extended period, it must be properly re-vented before power is restored to protect the heating element. No annual Gas Safe or G3 inspection is required.
