Heil – How to determine the age or manufacture date
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: 26 July 2009
There are at least two styles of serial numbers used found for Heil
Style 1
Heil – (1994 to present)
Serial Number format: L943321238
(This serial number is from an actual furnace).
Date of Manufacture: Using the second, third, fourth and fifth digits of the serial number L9433 21238 you will find the year and week of manufacture. The second and third digits are the year of manufacture and the fourth and fifth digits are the week. This unit was manufactured in the 33rd week of 1994.
Year of manufacture: L943321238
Week of manufacture: L943321238
Heil – (1980 thru 1989)
Serial Number format: H55116328
(This serial number is from actual air-conditioning unit).
Date of Manufacture: Using the first and second digits of the serial number H55116328 you will find the year of manufacture. The first digit (Always the letter “H” for the 1980’s) is the decade of manufacture and the second digit is the individual year of the decade. This unit was manufactured in 1985.
Decade of manufacture: H55116328
Year of manufacture: H55116328