LG EZ 2.5 kW (EZ09CYUCA31) 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 EZ 2.5 kW (EZ09CYUCA31)); LG EZ 2.5 kW (EZ09CYUCA31) 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 EZ 2.5 kW (EZ09CYUCA31) if running cost matters more.

manufacturer-declared, EPREL

LG EZ 2.5 kW (EZ09CYUCA31) and Panasonic BZ 2.5 kW (CU-BZ25CKE), estimated dB(A).

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.

LG EZ 2.5 kW (EZ09CYUCA31) against Panasonic BZ 2.5 kW (CU-BZ25CKE). Difference is left minus right.
Field	LG EZ 2.5 kW (EZ09CYUCA31)	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).

Estimated sound pressure. Scotland's legal point is a different sum and is not this column.
Distance	LG EZ 2.5 kW (EZ09CYUCA31) dB(A)	LG EZ 2.5 kW (EZ09CYUCA31) 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 LG EZ 2.5 kW (EZ09CYUCA31) · CSV of Panasonic BZ 2.5 kW (CU-BZ25CKE)

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.

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