Honeywell RTH7400 - Manuel (Page 4)

69-2487EF—01 2
Advanced Installation Guide
Remove old thermostat but leave wallplate with
wires attached.
2
Remove Old Thermostat
M28099
MERCURY NOTICE
Is there a sealed tube
containing mercury? If so,
see back cover for proper
disposal instructions.
Leave wallplate
in place
Old thermostat
Cover