How to determine the date of production/manufacture or age of REZNOR® HVAC Systems.
The date of production/manufacture or age of REZNOR® HVAC equipment can be determined from the serial number located on the data plate.

Parent Company:  Thomas & Betts Corporation

Example serial number styles/formats found:

  • Style 1: BKL79Y2N35171X
  • Style 2: 09087238A

Style 1:  BKL79Y2N35171X

The Date of Manufacture is coded in the 1st two or three digits of the serial number and represent the year and month of manufacture.

Style 2:   09087238A

Description: Nine (9) character serial number.

Month of manufacture is 1st & 2nd numerical digits.
Year of manufacture is 3rd & 4th numerical digits.

Page last updated: 19 April 2016

Nortek Global HVAC
8000 Phoenix Parkway
O’Fallon, MO 63368

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