Honeywell pro Series Professional Install Manual page 4

Setting Slider Tabs
Set R Slider Tab, see Figure 9.
• Use built-in jumper (R Slider Tab)
to differentiate between one or two
transformer systems.
• If there is only one R wire, and it is
connected to the R, Rc, or RH terminal
on the old thermostat, set the slider to
the up position (1 wire).
• If there is one wire connected to the R
terminal and one wire connected to the
Rc terminal, set the slider to the down
position (2 wires).
Set U Slider Tab, see Figure 10.
• Use built-in jumper (U Slider Tab) for
IAQ device.
• When the U Slider Tab is in the down
position (2 wires) the U contacts are a
dry set of contacts.
• If your IAQ device is powered by the
cooling transformer, move the U Slider
Tab to the up position (1 wire). When
this is done, the lower U terminal is
internally jumped to the Rc terminal.
In this application, you would hook
up one wire from your IAQ device to
the upper U terminal and the other
to the common side of the cooling
transformer. The 1 wire setting is most
commonly used when using a fresh
air damper for ventilation or using low
speed fan for dehumidification.
• See wiring examples on the next page.
9
10
4