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Models 9851i, 9865i and 9870i
Quick Start Installation Manual
111-340
Installation DOs and DON’Ts
DO
• Shut off all power to system before installing.
• Read entire manual before installing.
• Make sure that all wiring conforms to
national and local codes.
DO NOT
•
Install on voltages greater than 30 VAC.
• Short jumper across terminals on the gas
valve or at the system control.
• Connect ground to any terminal in
this unit.
• Install on outside walls or in direct sunlight.
Select location for installation.
Mark mounting hole locations on wall.
Drill 3/16” holes at marked locations on
wall. Insert plastic anchors into holes.
Align unit base over plastic anchors
embedded in wall and secure with the
screws provided.
Connect wiring between unit and
furnace. For Model 9851i (1H/1C
furnace applications):
6
1- 1/2"
1"
Cut
out
opening
1/4"
a
b
Mark mounting hole
locations on wall using
unit base as template.
Drill 3/16" holes
a
b
Press anchors into holes until flush.
Y1
R
C
E/W1
H O B G
Furnace
Terminals*
Wiring
Thermostat
C - Common 24 VAC
R - System transformer
Y1 - 1st stage cooling
W1- 1st stage heating
W2- not used
Y2 - not used
L - not used
O - Cool active reversing valve
B - Heat active reversing valve
G - Fan relay
D - Dehumidification relay
H - Humidification relay
TERMINAL DESIGNATIONS
W2
D
Y2
C
C
H
R
Y1
W1
L
G
L
B
O
* Please refer to furnace
installation manual for
proper terminations
Note: To avoid electrical problems, use the system transformer for both
the thermostat and humidifier.
9851
i
Humidifier
D
Remove 1/4” of insulation
from end of each wire
Open the case with a screwdriver. Place
in slot and gently pry forward at all four
locations.
2
1
2
3
4
DELUXE
PROGRAMMABLE
THERMOSTATS
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NOTE: For 9851i single stage heat
pump applications, place a jumper
between the W1 and Y1 terminals.
Connect wiring between unit and
furnace. For Model 9865i
(2H/2C furnace applications):
Replace cover on thermostat.
Turn on power to unit and proceed
with programming per instructions on
the display or in the user’s manual.
Connect wiring between unit and heat
pump. Jumper W2 to E/W1 for control
of auxiliary heat in both 2
nd
stage and
emergency modes. For Model 9870i
(2H/2C heat pump applications):
To set your name and phone
number into the thermostat press
MENU, select INSTALLER
SETTINGS, and CONTACT
INFORMATION. The screen at the
bottom left should appear.
To enter your name press EDIT.
Use the UP or DOWN button to
scroll through the characters.
(DOWN gets you to the letters
faster.) After each letter press NEXT.
When you are done entering your
name, press ACCEPT.
Connect wiring between the thermostat and the indoor sensor (9020i)
and the outdoor sensor (9025i), if
used. Use twisted pair wiring (22AWG
minimum) with a maximum length of
300 feet (or 100m).
Now enter your phone number.
Use the UP and DOWN arrow to
select the first number. Press NEXT.
When you have completed entering
your phone number, press ACCEPT.
The screen will return to the
INSTALLER SETTINGS. Finish
setting the thermostat for the
application.
Y1
R
C
E/W1
H O B G
Furnace
Thermostat
C - Common 24 VAC
R - System transformer
Y1 - 1st stage cooling
W1- 1st stage heating
W2- 2nd stage heating
Y2 - 2nd stage cooling
L - not used
O - Cool active reversing valve
B - Heat active reversing valve
G - Fan relay
D - Dehumidification relay
H - Humidification relay
TERMINAL DESIGNATIONS
W2
D
Y2
C
C
H
R
Y1
W1
W2
Y2
L
G
L
B
O
* Please refer to furnace
installation manual for
proper terminations
Note: To avoid electrical problems, use the system transformer for both
the thermostat and humidifier.
Humidifier
Wiring Terminals*
D
98
6
5
i
Y1
R
C
E/W1
H O B G
Heat Pump
Wiring
Terminals*
Thermostat
C - Common 24 VAC
R - System transformer
Y1 - Compressor output
E/W1 - Emergency heat relay
W2 - 2nd stage heating
Y2 - 2nd stage cooling
L - System check
O - Cool active reversing valve
B - Heat active reversing valve
G - Fan relay
D - Dehumidification relay
(to DS terminal)
H - Humidification relay
(to Humidifier)
TERMINAL DESIGNATIONS
W2
D
Y2
C
C
H
R
Y1
E/W1
W2
Y2
G
L
B
L
O
D
* Please refer to heat pump and
furnace installation manuals for
proper terminations
Note: To avoid electrical problems, use the system transformer for both
the thermostat and humidifier.
Humidifier
9870
i
Set Your Name Set Your Phone Number
Y1
R
C
E/W1
H O B G
Heat
Pump
Terminals*
Wiring
Thermostat
C - Common 24 VAC
R - System transformer
Y1 - 1st stage cooling
W1- 1st stage heating
W2- not used
Y2 - not used
L - not used
O - Cool active reversing valve
B - Heat active reversing valve
G - Fan relay
D - Dehumidification relay
H - Humidification relay
TERMINAL DESIGNATIONS
W2
D
Y2
C
C
H
R
Y1
W1
L
G
L
B
O
* Please refer to heat pump and
furnace installation manuals for
proper terminations
Note: To avoid electrical problems, use the system transformer for both
the thermostat and humidifier.
Humidifier
D
Jumper
9851
i
CONTACT INFORMATION
BACK
EDIT
ACCEPT
NEXT
CONTACT INFORMATION
AIR EXPERTS
CONTACT INFORMATION
AIR EXPERTS
ACCEPT
NEXT
1
ACCEPT
NEXT
CONTACT INFORMATION
AIR EXPERTS
1-555-555-1212
1
2
13
Recycling Thermostat
If this thermostat REPLACES a thermostat that contains
mercury, DO NOT discard the old thermostat in the regular
trash. Mercury is harmful to humans and the environment.
For this reason, do not open, break, or crush the mercury cell.
If mercury leaks from a damaged cell, DO NOT touch or handle
mercury with bare hands. Use protective, non-absorbent
gloves to place mercury into a sealable container. Fill the
container with sand or another absorbent material and seal
the container completely.
Return the mercury or mercury products, in a sealed container,
to Invensys Climate Controls or a local recycling center for
proper disposal. If you have any questions, call Robertshaw
technical support at 1-800-445-8299.
Invensys Climate Controls
28C Leigh Fisher Blvd.
El Paso, TX 79906
Attn: Mercury Recycling Center
Climate Controls Americas
515 South Promenade Avenue
Corona, CA 92879-1736
United States of America
Made in Mexico
www.about-i-series .com
111-340