Heat pumps · UK

Max WeishauptWWP LI 22-A R

The Max Weishaupt WWP LI 22-A R is an air-to-water heat pump with a SCOP of 4.55 (35 °C) and a sound power level of 56 dB(A). Under permitted development the limit is 37 dB(A) measured 1 m in front of the centre of a neighbour’s habitable-room door or window. Free-standing, the indicative minimum distance is 3.6 m; against a wall 5.0 m.1

Key figures

SCOP (35 °C)
4.551

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

Outdoor unit sound power
56dB(A)1
Official source
Refrigerant
R410A1
Official source
Rated output 35 °C
12.76kW1
Official source
Rated output 55 °C
12.39kW1
Official source
UK

Rules in the UK

Minimum distance to your neighbour

MCS 020(a) (England, permitted development since 29 May 2025)2 · 1 m in front of the centre of a neighbour’s habitable-room door or window

Permitted development (MCS 020(a)) ≤ 37 dB(A) · LAeq,5min
Free-standing 3.6 m
Against wall 5 m
In corner 7.1 m

Indicative calculation (hemispherical, no barriers). Not a substitute for an MCS 020 assessment.

Boiler Upgrade Scheme

Check conditions

£7,500 – £9,0003Fixed grant (England & Wales)

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.4,5

  • Must be MCS-certified (product and installer). Check the Ofgem product eligibility list.
  • Rated output 12.76 kW; the scheme covers systems up to 45 kW.
  • SCOP at 55 °C: 3.45. The installed system needs a SCOP of at least 2.8 (MCS calculation).
Heat pump grants in the UK explained →

Technical specifications

General
Type Air-to-water1
Compressors 21
Capacity control leistungsstufen1
Performance
Rated output 35 °C 12.76 kW1
Rated output 55 °C 12.39 kW1
Efficiency
SCOP (35 °C) 4.551
SCOP (55 °C) 3.451
Seasonal efficiency ηs 35 °C 179 %1
Seasonal efficiency ηs 55 °C 134.9 %1
COP A7/W35 5.051
COP A2/W35 4.051
COP A-7/W35 3.181
Noise
Outdoor unit sound power 56 dB(A)1
Indoor unit sound power 54 dB(A)1
Refrigerant
Refrigerant R410A1
Refrigerant charge 5.4 kg1
Electrical
Max. power input 8 kW1
Connectivity & smart
SG Ready Yes1

Frequently asked questions

Can I install the Max Weishaupt WWP LI 22-A R without planning permission?

Under MCS 020(a) (England, permitted development since 29 May 2025) the unit must not exceed 37 dB(A) 1 m in front of the centre of a neighbour’s habitable-room door or window. With a sound power of 56 dB(A) that indicatively means 3.6 m free-standing, 5.0 m against a wall or 7.1 m in a corner. Your MCS installer must confirm this.1

How much Boiler Upgrade Scheme grant can you get for the Max Weishaupt WWP LI 22-A R?

£7,500 in England and Wales, provided the product and installer are MCS-certified (£9,000 when replacing oil or LPG off the gas grid, until March 2027). The installer applies and deducts the grant from your quote.1

Which refrigerant does the Max Weishaupt WWP LI 22-A R use?

The Max Weishaupt WWP LI 22-A R uses R410A.1

Sources

  1. List of eligible heat pumps (BEG) — Bundesamt für Wirtschaft und Ausfuhrkontrolle (BAFA) · accessed 27 Sept 2026
  2. MCS 020(a) (England, permitted development since 29 May 2025)
  3. Boiler Upgrade Scheme: what you can get — GOV.UK · accessed 27 Sept 2026
  4. Boiler Upgrade Scheme: guidance for installers (V5) — Ofgem · accessed 27 Sept 2026
  5. Boiler Upgrade Scheme product eligibility — Ofgem · accessed 27 Sept 2026