approximate value of sound power level.

The restriction to noise in national standard is more strict and scientific. At present, freezer noise is required to take sound power level stipulated in national standard.

12.6.13 Why the noises of it type freezers are different?

Answer: The noise of each qualified freezer ex-factory is within the range of national standard. Different types of freezers have different powers, compressors used are not the same neither, and so their noises are

different. Even for same type freezers, as the noise of compressors are different, their differences to national standard 52dB(A) are not the same, and the noises are different.

12.6.14Why there are greater noises at starting and stopping of freezer?

Answer:

(1)At the starting of freezer, starting relay will make sound. The acceleration of motor will cause vibration of compressor and makes sound.

MAINTENANCE SERVICE AND TROUBLE SHOOTING Maintenance Service and Trouble Shooting

(2)When freezer stops, because of inertial rotation, there will be vibration sound from compressor.

46

PDF created with pdfFactory trial version www.pdffactory.com

Page 47
Image 47
Haier BD-478A service manual Why the noises of it type freezers are different?, Answer