Robertshaw 9415 - Manual (Page 6)

15. Set the GAS/ELEC switch to either GAS for a gas/oil heating
system or ELEC for an electric heating system (Figure 6).
16. Replace thermostat cover by snapping into place.
17. Turn on power to system. Test thermostat as described in the
following section.
6
GAS/ELECTRIC
Switch
Figure 6
TERMINAL LEGEND - 9415
TERM EQUIPMENT TO CONNECT REQ? TERMINAL FUNCTION
C 24VAC common connection Yes For input of 24VAC common
side of transformer
R 24VAC hot connection Yes For input of 24VAC hot side
of transformer
Y2 Second stage cooling connection No Energizes on a call for
second stage cooling (aux.)
Y1 First stage compressor connection Yes* Energizes on a call for first
stage of cooling
W1 First stage heat connection Yes* Energizes on a call for first
stage of heating
W2 Second stage heat connection No Energizes on a call for
second stage heating (aux.)
G Indoor fan connection Yes Energizes with W1, W2, Y1
and Y2 terminals or with
FAN option switched to the
ON position
O Accessory** No Energizes when in the in
COOL mode
B Accessory** No Energizes when in the
HEAT or EM modes
* This thermostat can be used as a heat only or cool only thermostat therefore it is not always
necessary to use both W1 and Y1.
** The O and B terminals are accessory terminals that typically are used for zoning applications.