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Dimplex SI
Model code: SI 18TU
✓ BUS eligible✓ MCS listedGround Source (GSHP)ResidentialHeating only
Heating capacity
17.5 kW
COP
4.7
B0/W35
Max flow temp
62°C
Sound power
50 dB(A)
Refrigerant
R410A
Boiler Upgrade Scheme
✓ BUS eligible
Listed on the Ofgem BUS Product Eligibility List (24 Sep 2026).
PEL certificate: MCS HP0017/32
Grant also needs an MCS-certified installer and a qualifying system design.
MCS certification
✓ MCS listed
Certificate: MCS HP0017/32
| General | |
|---|---|
| Heat pump type | Ground Source (GSHP) |
| Application | Residential |
| Refrigerant | R410A |
| Mode | Heating only |
| Heating performance | |
| Heating capacity | 17.5 kW |
| Max heating output (low temp) | 14.9 kW at B-5/W45 |
| COP (heating) | 4.7 at B0/W35 |
| Operating range (air) | -5 to 25 °C |
| Heating flow temperature | 20–62 °C |
| Electrical, acoustic and physical | |
| Power input | 7.2 kW |
| Electrical supply | 380-415V (Three Phase) |
| Sound power level | 50 dB(A) (Sound Power LW(A)) |
| Dimensions (H×W×D) | 840 × 650 × 655 mm |
| Operational Weight | 163 kg |
Test conditions: A = outdoor air °C, W = flow water °C (e.g. A7/W35 = 7°C air, 35°C flow). Compare COP and SCOP only at the same conditions.