LG MJ 2.5 kW (UUA1UL0) vs Panasonic BZ 2.5 kW (CU-BZ25CKE): which is quieter and cheaper to run?
Panasonic BZ 2.5 kW (CU-BZ25CKE) is ≈1.0 dB quieter outside (passes England's 37 dB limit from 8.9 m vs 10.0 m for LG MJ 2.5 kW (UUA1UL0)); LG MJ 2.5 kW (UUA1UL0) costs ≈£2.89 less per summer at 400 hours and 26.32p/kWh. Pick Panasonic BZ 2.5 kW (CU-BZ25CKE) if the unit goes close to a neighbour's window; pick LG MJ 2.5 kW (UUA1UL0) if running cost matters more.
manufacturer-declared, EPREL
Where the registered figures differ
The marker that opened this page: lwa, seer, scop, pass_distance. Both columns use the same tariff and the same noise setting.
| Field | LG MJ 2.5 kW (UUA1UL0) | Panasonic BZ 2.5 kW (CU-BZ25CKE) | Difference | Source |
|---|---|---|---|---|
| Outdoor sound power | 65.0 dB(A) | 64.0 dB(A) | +1.0 dB | manufacturer-declared, EPREL |
| SEER | 7.0 | 6.5 | +0.5 SEER | manufacturer-declared, EPREL |
| SCOP | 4.0 | 4.4 | −0.4 SCOP | manufacturer-declared, EPREL |
| Refrigerant | R32 | R32 | same | manufacturer-declared, EPREL |
| GWP | 675 | 675 | ≈0 GWP | manufacturer-declared, EPREL |
| £ per summer, 400 h | £37.60 | £40.49 | −£2.89 | calculated: capacity ÷ SEER × 400 h × price-cap rate |
| Observed price | — | £476.99 | — | shop observation |
| Distance to pass 37 dB | ≈10.0 m | ≈8.9 m | +1.1 m | calculated, MCS 020a, Q=2, no barrier |
| Cooling capacity | 2.5 kW | 2.5 kW | ≈0 kW | manufacturer-declared, EPREL |
Sound at a neighbour's window
Each distance is one outdoor unit, Q=2, no barrier, scored against England and Wales at 37 dB(A).
| Distance | LG MJ 2.5 kW (UUA1UL0) dB(A) | LG MJ 2.5 kW (UUA1UL0) vs 37 dB | Panasonic BZ 2.5 kW (CU-BZ25CKE) dB(A) | Panasonic BZ 2.5 kW (CU-BZ25CKE) vs 37 dB |
|---|---|---|---|---|
| 1 m | 57.0 | over | 56.0 | over |
| 2 m | 51.0 | over | 50.0 | over |
| 3 m | 47.5 | over | 46.5 | over |
| 4 m | 45.0 | over | 44.0 | over |
| 5 m | 43.0 | over | 42.0 | over |
| 8 m | 39.0 | over | 38.0 | over |
| 12 m | 35.4 | pass | 34.4 | pass |
EPREL manufacturer-declared registrations · snapshot 25 Sep 2026 · n=2 · pair source tier is the weaker of the two cards; 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 Estimated by MCS 020a Issue 1.1 for one unit, Q=2, no barrier, via contract_engine. £ per summer is capacity ÷ SEER × hours × 26.32p/kWh (2026-10-01 to 2026-12-31). The pair row lives in the compare index CSV.
Open the two cards
Better than a spec-sheet glance: the gap is scored at the same distances against the 37 dB line, and £ per summer uses one tariff.