York VCH-25A Installation Manual page 49

1 Installation manual
1.14 Unit sound power level indication (Lw in dB A)
N O T E
• Our reverberating chamber enables us to measure the sound pressure level at 63 Hz and, therefore,
the NC (ISO Noise Criteria) will be determined as of 125 Hz.
• Where the sound pressure value of 63 Hz is deduced, between 0 and 10 dB will be added to the
pressure value at 125 Hz
• The data given in this table are sound power values in accordance with ISO EN3743.
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