Honeywell RTH221 Owner's Manual

5  Mount Wallplate

Mount the new wallplate using the included screws and anchors.

Drill 3/16-in. holes for drywall
Drill 3/32-in. holes for plaster

6  Connect Wires

Simply match wire labels.
If labels do not match letters on the thermostat, check “Alternate Wiring” on 

page 6 and connect to terminal as shown (see notes, below).

Thermostat does not work on Heat Pumps with auxiliary/backup heat.

We are here to help. Call 1-800-468-1502 for wiring assistance.

M32714

Remove metal 

jumper if you 

have both 

 and 

 wires.

M32732

SCREW

INSERT WIRES 

AND TIGHTEN 

SCREWS

WIRE

HOLE

LABELED

WIRES