Every effort is undertaken to offer you correct and concise information to assist you in determining the age or manufacture date of HVAC equipment. Anytime anyone is dealing with numbers and letters in determining data, mistakes and misinterpretation are bound to happen. For this reason if you find during your research that we may have erred please contact us. In addition perhaps you have come across a brand, model or serial number format that we have not addressed. Email us information or pictures of data/nomenclature plates of the unit and we will attempt to assist you in your determinations. Email
This page was last updated: 25 July 2009
Comfortmaker
Serial Number format: L004112345
(This serial number is fictitious).
Using the second, third, fourth and fifth digits of the serial number L004112345you will find the year and week of manufacture. The second and third digits are the year and the fourth and fifth digits are the week. This unit was manufactured in the 41st week of 2000.
Year of manufacture: L004112345
Week of manufacture: L004112345