Serial Number Format
Water Heaters and Direct Vent Furnaces
On direct vent furnaces manufactured before June 1, 2010, the Rinnai serial number will consist of four numbers,
followed by a dash, followed by six numbers. The first four numbers are separated by a period (.). The first two
numbers indicate the year and the next two numbers indicate the month.
Example: 03.06-001000 This unit was manufactured in 2003 (03) and the sixth month (June) – (06).
On direct vent furnaces manufactured on or after June 1, 2010 the Rinnai serial number will consist of four
letters, followed by a dash, followed by six numbers. The first letter indicates the year of manufacture and the
second letter indicates the month of manufacture according to the table below.
Example: BH.AB-000123 This product was manufactured in August, 2010.
The third and fourth letters indicate manufacturing location and product type. The 6 digit number will be
sequential and reset every year.
Year/Month Table
For applicable models and manufacturing dates: the first letter indicates the year of manufacture
Year
2009
A
2010
B
2011
C
2012
D
2013
E
2014
F
2015
G
2016
H
2017
J
2018
K
2019
L
2020
M
Rinnai Direct Vent Service Manual
the second letter indicates the month of manufacture.
Year
2021
N
2022
P
2023
R
2024
S
2025
T
2026
W
2027
X
2028
Y
2029
Z
Month
January
A
February
B
March
C
April
D
May
E
June
F
July
G
August
H
September
J
October
K
November
L
December
M
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