Year Setting (First Two Digits); Year Setting (Second Two Digits); Month Setting; Date Setting - Honeywell RTH8500 Installation Manual

System setup

Year setting (first two digits)

Function
Press
0120
Options: 20 = Year 20xx
21 = Year 21xx

Year setting (second two digits)

Function
Press
0130
Options:
01 -

Month setting

Function
Press
0140
Options: 01 -

Date setting

Function
Press
0150
Options: 01 -
to change the first two digits of the year:
s/t
to change the last two digits of the year:
s/t
(i.e., 2001 - 2099)
99
to change the current month:
s/t
12 (i.e., January - December)
to change the current date:
s/t
31

RTH8500