versusindex
UK
Heat pumps · UK

iDMTERRA SW 35 Twin (Wasser / Wasser)

The iDM TERRA SW 35 Twin (Wasser / Wasser) is a heat pump with SCOP (35 °C) 7.45 and refrigerant R410A.1

Last updated: Technical specifications Rules in the UK ⇄ Compare this model
Search this model
SCOP (35 °C)
7.451

Seasonal efficiency: how much heat you get per kWh of electricity across a heating season.

Refrigerant
R410A1
Official source
Type (source)
Water-to-water1
Official source
Rated output 35 °C
46.4kW1
Official source
Rated output 55 °C
43.6kW1
Official source
UK

Rules in the UK

Boiler Upgrade Scheme

Not eligible

Fixed grant in England and Wales, deducted from your installer’s quote. £9,000 when replacing oil or LPG off the gas grid (until March 2027). Scotland: Home Energy Scotland grant instead.3,4

  • Must be MCS-certified (product and installer). Check the Ofgem product eligibility list.
  • Rated output 46.4 kW; the scheme covers systems up to 45 kW.
  • SCOP at 55 °C: 5.58. The installed system needs a SCOP of at least 2.8 (MCS calculation).
Heat pump grants in the UK explained →

Technical specifications

General
Type (source) Water-to-water1
Compressors 21
Capacity control leistungsstufen1
Performance
Rated output 35 °C 46.4 kW1
Rated output 55 °C 43.6 kW1
Efficiency
SCOP (35 °C) 7.451
SCOP (55 °C) 5.581
Seasonal efficiency ηs 35 °C 290 %1
Seasonal efficiency ηs 55 °C 215 %1
Noise
Indoor unit sound power 54 dB(A)1
Refrigerant
Refrigerant R410A1
Refrigerant charge 8.2 kg1
Electrical
Max. power input 7.24 kW1
Connectivity & smart
SG Ready Yes1

Frequently asked questions

What is the SCOP (35 °C) of the iDM TERRA SW 35 Twin (Wasser / Wasser)?

The SCOP (35 °C) of the iDM TERRA SW 35 Twin (Wasser / Wasser) is 7.45.1

Which refrigerant does the iDM TERRA SW 35 Twin (Wasser / Wasser) use?

The refrigerant of the iDM TERRA SW 35 Twin (Wasser / Wasser) is R410A.1

How much Boiler Upgrade Scheme grant can you get for the iDM TERRA SW 35 Twin (Wasser / Wasser)?

Probably none. Rated output 46.4 kW; the scheme covers systems up to 45 kW.1

Sources

  1. List of eligible heat pumps (BEG) — Bundesamt für Wirtschaft und Ausfuhrkontrolle (BAFA) · accessed 28 Sept 2026
  2. Boiler Upgrade Scheme: what you can get — GOV.UK · accessed 27 Sept 2026
  3. Boiler Upgrade Scheme: guidance for installers (V5) — Ofgem · accessed 27 Sept 2026
  4. Boiler Upgrade Scheme product eligibility — Ofgem · accessed 27 Sept 2026