Service Manual

3
3
Determining the Age of Your Water Heater
The first two characters of the serial number represent the year and month of manufacture. The
remainder of the serial is a sequential production number, seven digits in length before December
2007 (DM), and eight digits in length after.
For example:
For the year column, we do not use the letters: I, O, Q, R U, V
For the month column we do not use the letters: I & N – Z
Due to a computer error there were some OA serial water heaters manufactured.
They were built in January of 1997.
NOTICE
This Service Manual is ONLY for ICON Control Systems (Serial Numbers XC and later for 125,199
and 270 kBTU systems,
NA37235769 and later for ). Please make sure that your water heater falls within this range.
UCG80H125(N,X)
XC and Later
UCG(80,100)H199*(N,X)(A)
XC and Later
UCG(80,100)H270*(N,X)(A)
XC and Later
UCG80H399*(N,X)
NA37235769 and Later
UCG100H399*(N,X)
LM35401146 and Later
Production Year
A = 1984 or 2004
L = 1994 or 2014
B = 1985 or 2005
M = 1995 or 2015
C = 1986 or 2006
N = 1996 or 2016
D =1987 or 2007
P = 1997 or 2017
E = 1988 or 2008
S = 1998 or 2018
F = 1989 or 2009
T = 1999 or 2019
G = 1990 or 2010
W = 2000 or 2020
H = 1991 or 2011
X = 2001 or 2021
J = 1992 or 2012
Y =2002 or 2022
K = 1993 or 2013
Z = 2003 or 2023
Production Month
A = January
G = July
B = February
H = August
C = March
J = September
D =April
K = October
E = May
L = November
F = June
M = December