Quietest 5 kW (18,000 BTU) air conditioners in the UK: 11 models that pass 37 dB at 4 m
Olimpia Splendid OSSENEH 5.3 kW (OS-CANMH18EI / OS-SENEH09EI) is the quietest of these 11 that pass at 4 m, at ≈34.0 dB(A). If the outdoor unit will sit closer than 4 m to a neighbour's window, use the 4 m column before you shortlist.
computed
Ranked models
11 models match this list. Sound pressure at 4 m, low to high, among passes.
| Rank | Model | LwA dB(A) | 3 m dB(A) | SEER | £ at 400 h | Refrigerant | Observed price |
|---|---|---|---|---|---|---|---|
| 1 | Olimpia Splendid OSSENEH 5.3 kW (OS-CANMH18EI / OS-SENEH09EI) | 54.0 | 36.5 | 6.8 | £82.06 | R32 | — |
| 2 | Haier AD 5 kW (1U50S2SJ2FA / AD50S2SM3FA) | 55.0 | 37.5 | 6.1 | £86.30 | R32 | — |
| 3 | Mitsubishi Electric Elegance 5.3 kW (MXZ-2F53VFHZ2-E1) | 55.0 | 37.5 | 6.0 | £93 | R32 | — |
| 4 | Mitsubishi Electric Elegance 5.3 kW (MXZ-2F53VFHZ3) | 55.0 | 37.5 | 6.0 | £93 | R32 | — |
| 5 | Mitsubishi Electric MFZKT 5.3 kW (MXZ-2F53VFHZ2-E1) | 55.0 | 37.5 | 6.0 | £93 | R32 | — |
| 6 | Mitsubishi Electric MFZKT 5.3 kW (MXZ-2F53VFHZ3) | 55.0 | 37.5 | 6.0 | £93 | R32 | — |
| 7 | Mitsubishi Electric Premium 5.3 kW (MXZ-2F53VFHZ) | 55.0 | 37.5 | 6.8 | £82.06 | R32 | — |
| 8 | Mitsubishi Electric Premium 5.3 kW (MXZ-2F53VFHZ2) | 55.0 | 37.5 | 6.8 | £82.06 | R32 | — |
| 9 | Mitsubishi Electric Premium 5.3 kW (MXZ-2F53VFHZ3) | 55.0 | 37.5 | 6.8 | £82.06 | R32 | — |
| 10 | Mitsubishi Electric SLZM 5.3 kW (MXZ-2F53VFHZ2-E1) | 55.0 | 37.5 | 6.3 | £88.57 | R32 | — |
| 11 | Mitsubishi Electric SLZM 5.3 kW (MXZ-2F53VFHZ3) | 55.0 | 37.5 | 6.3 | £88.57 | R32 | — |
EPREL manufacturer-declared registrations · snapshot 25 Sep 2026 · n=11 · Sound pressure at 4 m, low to high, among passes; noise via contract_engine MCS 020a Q=2, no barrier · updated 25 Sep 2026 · version 1.0.0 · CSV of the values on this page
How this page was calculated
If the calculated sound pressure level at all assessment positions is equal to or lower than 37.0 dB(A) then the heat pump will comply with the Permitted Development noise limit
Other lists at this capacity
- Quietest 5 kW (18,000 BTU) air conditioners in the UK
- R32 5 kW (18,000 BTU) air conditioners in the UK
- Highest-SEER 5 kW (18,000 BTU) air conditioners in the UK
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- Lowest observed prices for 5 kW (18,000 BTU) air conditioners
Better than a best-of roundup with no figures: every row is a registered number and a link to the model card.