STIEBEL ELTRON LWZ 05.1 Premium HKWL 230 vs Thermia iTec XTR S 230-1
SCOP (35 °C): STIEBEL ELTRON LWZ 05.1 Premium HKWL 230 4.28, Thermia iTec XTR S 230-1 5.1. The Thermia iTec XTR S 230-1 is better on 10 of 14 comparable points.
Who wins where
- STIEBEL ELTRON LWZ 05.1 Premium HKWL 230
- Thermia iTec XTR S 230-1
Biggest differences
| Fact | LWZ 05.1 Premium HKWL 230 | iTec XTR S 230-1 |
|---|---|---|
| Heating capacity (A7/W35) | 2.26 kW | 5 kW |
| Refrigerant charge | 1.24 kg | 0.63 kg |
| Seasonal efficiency ηs 35 °C | 168 % | 201 % |
| SCOP (35 °C) | 4.28 | 5.1 |
| Seasonal efficiency ηs 55 °C | 128 % | 141 % |
| SCOP (55 °C) | 3.28 | 3.6 |
Score per area = position (0–100) relative to all 1350 models in this category; higher is better.
| Technical specifications | STIEBEL ELTRONLWZ 05.1 Premium HKWL 230 | ThermiaiTec XTR S 230-1 |
|---|---|---|
| Grants & market | ||
| Boiler Upgrade Scheme | £7,500 – £9,000 | £7,500 – £9,000 |
| General | ||
| Type (source) | Air-to-water 1 | Air-to-water 1 |
| Performance | ||
| Heating capacity (A7/W35) | 2.26 kW 2 | 5 kW ✓ 3 |
| Rated output 35 °C | 5.47 kW 1 | 5.5 kW ✓ 1 |
| Rated output 55 °C | 5.44 kW 1 | 5.5 kW ✓ 1 |
| Efficiency | ||
| SCOP (35 °C) | 4.28 1 | 5.1 ✓ 1 |
| SCOP (55 °C) | 3.28 1 | 3.6 ✓ 1 |
| Seasonal efficiency ηs 35 °C | 168 % 1 | 201 % ✓ 1 |
| Seasonal efficiency ηs 55 °C | 128 % 1 | 141 % ✓ 1 |
| Energy label 35 °C | A, , 2 | A, , , 3 |
| Energy label 55 °C | A, , 2 | A, , 3 |
| COP A7/W35 | 5.55 ✓ 1 | 5.1 1 |
| COP A2/W35 | 4.14 1 | 4.31 ✓ 1 |
| COP A-7/W35 | 2.9 1 | 2.99 ✓ 1 |
| Noise | ||
| Outdoor unit sound power | 55 dB(A) 1 | 55 dB(A) 1 |
| Indoor unit sound power | 53 dB(A) 1 | – |
| Refrigerant | ||
| Refrigerant | R290 1 | R290 1 |
| Refrigerant GWP | 3 2 | 3 3 |
| Refrigerant charge | 1.24 kg 1 | 0.63 kg ✓ 1 |
| Electrical | ||
| Max. power input | 12.2 kW 1 | 3.19 kW 1 |
| Connectivity & smart | ||
| SG Ready | Yes 1 | Yes 1 |
| Grants & market | ||
| ISDE grant (NL) | 2,150 € 4 | – |
Sources
- List of eligible heat pumps (BEG) — Bundesamt für Wirtschaft und Ausfuhrkontrolle (BAFA) · accessed 27 Sept 2026
- Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026
- Heat Pump Keymark certificates — EHPA / DIN CERTCO (Heat Pump KEYMARK) · accessed 29 Sept 2026
- ISDE heat pump notification code list — Rijksdienst voor Ondernemend Nederland (RVO) · accessed 28 Sept 2026