Pro 1 IAQ True Comfort T855 User manual

This manual covers the following models:
• T855
INSTALLATION MANUAL
A trained, experienced technician
must install this product.
Carefully read these instructions. You
could damage this product or cause a
hazardous condition if you fail to follow
these instructions.
Need Help?
For assistance with this product please visit
http://www.pro1iaq.com or call Pro1
Customer Care toll-free at 888-Pro1iaq
(776-1427) during normal business hours
(Mon-Fri 9 AM - 6 PM Eastern)
Table of Contents
Thermostat Applications Guide
Page
Battery Power
Hardwire (Common Wire)
Hardwire (Common Wire) with Battery Backup
Power Type
1
noitpircseD
Gas or Oil Heat
Electric Furnace
Heat Pump (No Aux. or Emergency Heat)
Heat Pump (with Aux. or Emergency Heat)
Multi-stage Systems
Heat Only Systems
Heat Only Systems
Cool Only Systems
Millivolt
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Rev. 0850
Una versión española de este
manual puede ser descargada
en www.pro1iaq.com
® U.S. Registered Trademark. Patents pending.
Copyright © 2006 Pro1 IAQ, Inc. All rights reserved.
Installation Tips
Thermostat Quick Reference
Subbase Installation
Wiring
Technician Setup Menu
Mounting and Battery Installation
Programming The Thermostat
Specifications
2
3
4
5
6-8
9
10-12
13

INSTALLATION TIPS
The thermostat should be installed approximately 4 to 5 feet above the floor.
Select an area with average temperature and good air circulation.
Do not install thermostat in locations:
• Close to hot or cold air ducts
• That are in direct sunlight
• With an outside wall behind the thermostat
• In areas that do not require conditioning
• Where there are dead spots or drafts (in corners or behind doors)
• Where there might be concealed chimneys or pipes
Pick an installation location that is easy for the user to access. The temperature of the location
should be representative of the building.
Wall locations
2
PRO1 Tip
NO
NO NO YES

3
Getting to know your thermostat
LCD
1
2
Fan Button
3
System Button
4
Menu Buttons Access Door
5
Temperature Setpoint Buttons
6
Menu Button
7
User Program Buttons
8
Hold is displayed when
thermostat program is
permanently overridden.
+1 will appear in the
display when second
stage of heat or cool
is on.
+2 will appear in the
display when third stage
of heat is on.
System operation
indicators: The COOL,
HEAT or FAN icon will
display when the COOL,
HEAT or FAN is on.
NOTE: The compressor
delay feature is active if
these icons are flashing.
The compressor will not
turn on until the 5 minute
delay has elapsed.
Days of the
week and time
Glow in the Dark Light Button
6
7
8
1
2
3 4
5
Low Battery Indicator:
Replace batteries when
this indicator is shown.
Program Menu Options:
Shows different options
during programming.
Indicates the
current room
temperature.
Programmable
Time Period Icons:
This thermostat has
4 programmable time
periods per day.
Important:
The low battery indicator is displayed
when the AA battery power is low. If the
user fails to replace the battery within
21 days, the thermostat display will only
show the low battery indicator as a final
warning before the thermostat
becomes inoperable. The batteries are
located on the back of the thermostat.
Displays the user
selectable setpoint
temperature.

UP
SUBBASE INSTALLATION
4
Caution:
Electrical Hazard
Failure to disconnect the
power before beginning to
install this product can cause
electrical shock or equipment
damage.
Mercury Notice:
All of Pro1’s products are
mercury free. However, if the
product you are replacing
contains mercury, dispose of it
properly. Your local waste
management authority can give
you instructions on recycling
and proper disposal.
Horizontal mount
Horizontal mount
Vertical mount
Vertical mount
For vertical mount put
one screw top and one
screw bottom.
For horizontal mount put
one screw left and one
screw right.
C
O
B
W/E
W2
R
G
Y
Y2

WIRING
5
C terminal
The C(common wire) terminal does not
have to be connected when the thermostat is
powered by batteries.
PRO1 Tips:
Terminal Designations
Terminal 2 Heat 2 Cool
Conventional System
2 Heat 2 Cool
Heat Pump System 3 Heat 2 Cool Heat Pump System
RC
RH
C
B
O
G
W/E
Y
Y2
W2
Transformer power
(cooling)
Transformer power
(heating)
Transformer common
Energized in heating
Energized in cooling
Fan relay
First stage of heat
First stage of cool
Second stage of cool
Second stage of heat
Transformer power
(cooling)
Transformer power
(heating)
Transformer common
Heat pump changeover valve
energized in heating
Heat pump changeover valve
energized in cooling
Fan relay
Emergency heat relay
First stage of heat & cool
Second stage of cool
Auxiliary heat relay,
second stage of heat
Transformer power
(cooling)
Transformer power
(heating)
Transformer common
Heat pump changeover valve
energized in heating
Heat pump changeover valve
energized in cooling
Fan relay
Emergency heat relay
First stage of heat & cool
Second stage of cool
& second stage of heat
Auxiliary heat relay,
third stage of heat
This thermostat is shipped from the factory to operate a conventional heating and cooling system. This thermostat will
also operate a heat pump system. See the “heat pump” configuration step on page 8 of this manual to configure the
thermostat for heat pump applications.
Warning:
All components of the control
system and the thermostat
installation must conform to
Class II circuits per the NEC Code.
Note:
In many systems with no emergency
heat relay a jumper can be installed
between E and W2.
Wiring
If you are replacing a thermostat, make
note of the terminal connections on the
thermostat that is being replaced. In some
cases the wiring connections will not be
color coded. For example, the green wire
may not be connected to the Gterminal.
Loosen the terminal block screws. Insert
wires then retighten terminal block screws.
Place nonflammable insulation into wall
opening to prevent drafts.
1.
2.
3.
Wire specifications
Use shielded or non-shielded
18 - 22 gauge thermostat wire.

6
TECHNICIAN SETUP MENU
Note: To lock the keypad hold down the and keys for 3
seconds. You will see a lock in the display. To unlock the keypad
hold down the and keys for 3 seconds.
Technician Setup Menu
This thermostat has a technician setup menu
for easy installer configuration. To set up the
thermostat for your particular application:
Configure the installer options as
desired using the table below.
Use the or keys to
change settings and the NEXT STEP
or PREV STEP key to move from one
option to another. Note: Only press
DONE key when you want to exit the
Technician Setup options.
Press MENU button
Press and hold TECHNICIAN SETUP
button for 3 seconds. This 3 second delay
is designed so that homeowners do not
accidentally access the installer settings.
1.
2.
3.
This feature will
flash FILT in the
display after the
elapsed run time
to remind the
user to change the
filter. A setting of
OFF will disable
this feature.
This feature allows
the installer to
change the
calibration of the
room temperature
display. For
example, if the
thermostat reads 70°
and you would like it
to read 72° then
select +2.
The compressor short
cycle delay protects
the compressor from
“short cycling”. This
feature will not allow
the compressor to be
turned on for 5
minutes after it was
last turned off.
The swing setting,
often called “cycle
rate”, “differential”
or “anticipation” is
adjustable. A smaller
swing setting will
cause more frequent
cycles and a larger
swing setting will
cause fewer cycles.
The swing setting,
often called “cycle
rate”, “differential”
or “anticipation” is
adjustable. A
smaller swing setting
will cause more
frequent cycles and a
larger swing setting
will cause fewer
cycles.
Keypad lockout
allows you to
configure the
thermostat so that
none or some of
the keys do not
function.
The heating swing
setting is adjustable
from ±0.4°F to
±2°F. For example:
A swing setting of
0.5°F will turn the
heating on at
approximately 0.5°F
below the setpoint
and turn the heating
off at approximately
0.5°F above the
setpoint.
Pick PA or FU
PA = partial keypad
lockout, which locks
all the keys except the
or keys.
FU = Full keypad
lockout, which locks
out all the keys.
Note: Keypad lockout
instructions are below.
The cooling swing
setting is adjustable
from ±0.4°F to
±2°F. For example:
A swing setting of
0.5°F will turn the
cooling on at
approximately 0.5°F
above the setpoint
and turn the cooling
off at approximately
0.5°F below the
setpoint.
Selecting ON will not
allow the compressor
to be turned on for 5
minutes after the last
time the compressor
was on. Select OFF
to remove this delay.
You can select the
minimum compressor
run time from “off”,
“3”, “4”, or “5”
minutes. If 3, 4, or 5
is selected, the
compressor will run
for at least the
selected time before
turning off.
You can adjust the
room temperature
display to ready -4°F
to +4°F above or
below the factory
calibrated reading.
You can adjust
the filter change
reminder from
OFF to 2000
hours of runtime
in 50 hour
increments.
OFF 0 ºF OFF ON 0.5 ºF 0.4 ºF NA
TECH SETUP
STEPS CONTINUED
ON THE NEXT PAGE
This feature allows the
installer to select the
minimum run time for
the compressor.
For example, a setting
of 4 will force the
compressor to run for
at least 4 minutes
every time the
compressor turns on,
regardless of the room
temperature.
Tech Setup Steps
Minimum
Compressor
On Time
Compressor
Short Cycle
Delay
Cooling
Swing
Heating
Swing
Keypad
Lockout
Room
Temperature
Calibration
Filter
Change
Reminder

7
TECHNICIAN SETUP MENU
TECH SETUP
STEPS CONTINUED
ON THE NEXT PAGE
Use the or
key to select the
maximum heat
setpoint.
90 ºF
Adjustment Options
Factory Default Settings
This feature
allows you to set a
maximum heat
setpoint value.
The setpoint
temperature
cannot be raised
above this value.
Tech Setup Steps (Continued from the previous page)
Heating
Temperature
Setpoint Limit
GAS
or
ELEC
GAS
Select GAS for
systems that control
the fan during a call
for heat.
Select ELEC to have
the thermostat
control the fan during
a call for heat.
Fan
Operation
LCD Will Show
Use the or
key to select the
minmum cool
setpoint.
44 ºF
This feature
allows you to set a
minimum cool
setpoint value.
The setpoint
temperature
cannot be lowered
below this value.
Cooling
Temperature
Setpoint Limit
Use the or
key to select 12 or 24
hour clock.
12 Hour Clock
You can select
either a 12 or 24
hour clock setting.
12 or 24
Hour Clock
Use the or
key to turn on or off.
ON
This feature turns your
system on before the
WAKE programming
time to ensure the
enviroment is at the
WAKE setpoint when
the WAKE time period
begins. This recovery
changes over time
based on the previous
days experience.
Morning
Recovery
Use the or
key to select 7d for 7
day, 5d for 5+1+1,
or 0d for
nonprogammable.
5d
You can configure this
thermostat to have a
7 day program, a
5+1+1 program or
nonprogrammable.
Program
Options
Select Ffor
Fahrenheit
temperature read
out or select Cfor
Celsius read out
ºF for Fahrenheit
ºC for Celsius
ºF
ºF or ºC
The second stage will turn on at 2x the swing setting. The second stage will turn off when 1x the
swing is reached. For example, if the swing setting is .8 degrees for heating and the thermostat is
set at 70ºF, the first stage will turn on at approximately 69.2ºF. The second stage will turn on at
68.4ºF. The second stage will turn off at 69.2ºF and the first will turn off at 70.8ºF. If third stage is
used, it will turn on at 3x the swing and turn off at approximately 2x the swing.
PRO1 Tip

8
TECHNICIAN SETUP MENU
If ON is selected
the beep will
sound. If
OFF is selected,
there is no sound.
OFF configures
display light to
come on only with
the light key,
which will save
battery power.
ON configures the
display light to
come on when any
key is pressed.
OFF configures
the thermostat
for non heat
pump systems
ON configures
the thermostat
for heat pump
systems
ON OFF ON OFF
Adjustment Options
Factory Default Settings
The display light
can be configured
to come on when
any key is pressed
or only when the
light key is
pressed.
When any key
is pressed an
audible beep
will sound.
You can choose
ON or OFF
When turned on
the thermostat
will operate a
heat pump.
1. EM.Heat will
show as an option
in the system
switch.
2. Y will be first
stage of heat &
cool, W/E will be
emergency heat
relay & W2 will
be auxiliary heat
relay.
Allows you to put
your phone number
in the display.
You can choose
ON or OFF
Tech Setup Steps (Continued from the previous page)
Contractor
Call Number
Beep Heat PumpDisplay
Light
LCD Will Show
Heat - Off - Cool
You can configure the
system switch for the
particular application:
Heat - Off - Cool,
Heat - Off,
Cool - Off,
Heat - Off - Cool-Auto
Note: EM. Heat will
show if in heat pump
mode.
System
Switch
Gas Auxiliary
for Heat Pump
Stages
of Heat
Cooling Fan
Delay
Use the or
key until the desired
application is
flashing.
OFF OFF2 Stages
Use the or
key to select the
desired number and
the FAN or SYSTEM
key to move from
one character to
another. See note
below on operation.
If selected on, you
will see the input
screen after pressing
next step.
Note: If Contractor Call Number is selected ON, your phone number
will show in the display if there has been a continuous call for heating
or cooling for 24 hours or if the light button is held down for 3 seconds.
To remove the phone number from the display, hold the light button
down for 3 seconds.
You can configure the
thermostat to operate
a 3 stage heat pump
system.
2H 2C = 2 heat, 2 cool
3H 2C = 3 heat, 2 cool
The cooling fan delay
setting will delay the
fan from coming on in
cool mode and keep
running after the
compressor shuts off
for a short time to save
energy in some
systems.
You can select the
Cooling Fan Delay
from "Off" "15" "30"
"60" or "90" seconds.
If 15 30 60 or 90 is
selected the fan will
not turn on for that
many seconds when
there is a call for cool
and will run for that
many seconds after
satisfying a call for
cool.
Use the or
key to change between
2 heat and 3 heat.
2 heat will use Y1 as
first stage and W2 as
auxiliary.
3 heat will use Y1 as
first stage, Y2 as
second stage and
W2 as auxiliary.
This option will turn
the heat pump off 45
seconds after the
auxiliary heat relay
turns on.
For 2 heat
applications, the first
stage will turn off 45
seconds after the
auxiliary stage turns
on.
For 3 heat
applications, the first
and second stage will
turn off 45 seconds
after the auxiliary
stage turns on.
For heat pump
systems that are
“dual fuel” (use a
gas furnace for
auxiliary stage heat)
you can turn this
feature on to turn off
the heat pump when
the auxiliary stage of
heating has been
called for.

9
MOUNT THERMOSTAT & BATTERY INSTALLATION
Mount Thermostat
Align the 4 tabs on the subbase with
corresponding slots on the back of the
thermostat, then push gently until the
thermostat snaps in place.
On the back of the thermostat insert
2 AA Alkaline batteries (included).

10
PROGRAMMING THE THERMOSTAT
Set Time
Programming
Weekday Wake 6 a.m. 70° F (21° C) 75° F (24° C)
Leave 8 a.m. 62° F (17° C) 83° F (28° C)
Return 6 p.m. 70° F (21° C) 75° F (24° C)
Sleep 10 p.m. 62° F (17° C) 78° F (26° C)
Factory Default Program
Saturday Wake 8 a.m. 70° F (21° C) 75° F (24° C)
Leave 10 a.m. 62° F (17° C) 83° F (28° C)
Return 6 p.m. 70° F (21° C) 75° F (24° C)
Sleep 11 p.m. 62° F (17° C) 78° F (26° C)
Sunday Wake 8 a.m. 70° F (21° C) 75° F (24° C)
Leave 10 a.m. 62° F (17° C) 83° F (28° C)
Return 6 p.m. 70° F (21° C) 75° F (24° C)
Sleep 11 p.m. 62° F (17° C) 78° F (26° C)
Day of the
Week
Setpoint
Temperature (Cool)
Setpoint
Temperature (Heat)
TimeEvents
Follow the steps below to set the day of the week and current time:
Press MENU
Press SET TIME
Day of the week will be flashing. Use the or key to select the current
day of the week.
Press NEXT STEP
The current hour is flashing. Use the or key to select the current hour.
When using 12-hour time, make sure the correct a.m. or p.m. choice is selected.
Press NEXT STEP
Minutes are now flashing. Use the or key to select current minutes.
Press DONE when completed
1.
2.
3.
4.
5.
6.
7.
8.
All programmable Pro1 thermostats are shipped with an energy saving pre-program. You can customize this
default program by following the Set Program Schedule.
Your thermostat can be programmed to have each day of the week programmed uniquely (7 days), all the
weekdays the same, a separate program for Saturday, and a separate program for Sunday (5+1+1), or non-
programmable. This thermostat has a programmable fan feature, which allows you to run the fan continuously
during any time period. There are four time periods for each program (WAKE, LEAVE, RETURN, SLEEP).

11
PROGRAMMING THE THERMOSTAT
Weekday Wake
Leave
Return
Sleep
Programming Table
Saturday
Sunday
You can use the table below to plan your customized program schedule if using 5+1+1.
Set Program Schedule
To customize your 5+1+1 program schedule, follow these steps
Weekday:
Saturday:
Sunday:
Select HEAT or COOL using the SYSTEM key.
Note: You have to program heat and cool each
separately.
Press MENU
Press SET SCHED. Note: Monday-Friday is displayed and the
WAKE icon is shown. You are now programming the WAKE time
period for the weekday setting.
Time is flashing. Use the or key to make your time
selection for the weekday WAKE time period. Note: If you want
the fan to run continuously during this time period, select ON with
the FAN key.
Press NEXT STEP
The setpoint temperature is flashing. Use the or key
to make your setpoint selection for the weekday WAKE period.
Press NEXT STEP
Repeat steps 4 through 7 for weekday LEAVE time period, for
weekday RETURN time period, and for weekday SLEEP time
period.
Repeat steps 4 through 7 for
Saturday WAKE time period,
for Saturday LEAVE time
period, for Saturday RETURN
time period, and for Saturday
SLEEP time period.
Repeat steps 4 through 7 for
Sunday WAKE time period,
for Sunday LEAVE time
period, for Sunday RETURN
time period, and for Sunday
SLEEP time period.
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
Wake
Leave
Return
Sleep
Wake
Leave
Return
Sleep
Day of the
Week
Setpoint
Temperature (Cool)
Setpoint
Temperature (Heat)
TimeEvents

To customize your 7 day program schedule, follow these steps:
Select HEAT or COOL using the system key. You have to program heat and cool each separately.
Press MENU
Press SET SCHED
Note: Monday is displayed and the WAKE icon is shown. You are now programming the WAKE
time period for the Monday setting.
Time is flashing. Use the or key to make your time selection for the Monday WAKE
time period. Note: If you want the fan to run continuously during this time period, select ON with
the FAN key.
Press NEXT STEP
The setpoint temperature is flashing. Use the or key to make your setpoint selection
for the Monday WAKE period.
Press NEXT STEP
Repeat steps 4 thru 7 for Monday LEAVE time period, for Monday RETURN time period, and for
Monday SLEEP time period.
PROGRAMMING THE THERMOSTAT
12
1.
2.
3.
4.
5.
6.
7.
8.
Monday
Repeat steps 4 thru 7 for the remaining days of the week.
Tuesday, Wednesday, Thursday, Friday, Saturday, Sunday
A Note About Auto Changeover:
Auto changeover will switch between heating
and cooling as needed. It is very important to
make sure the cooling setpoint temperature is at
least 3º above the heating setpoint temperature
and that the heating setpoint temperature is at
least 3º below the cooling setpoint temperature.
A Note About Programmable Fan:
The programmable fan feature will
run the fan continuously during any
time period it is programmed to be
on. This is the best way to keep the
air circulated and to eliminate hot &
cold spots in your building.

The display range of temperature
The control range of temperature
Load rating
Display accuracy
Swing (cycle rate or differential)
Power source
Operating ambient
Operating humidity
Dimensions of thermostat
41ºF to 95ºF (5ºC to 35ºC)
44ºF to 90ºF (7ºC to 32ºC)
1 amp per terminal, 1.5 amp maximum all terminals combined
± 1ºF
Heating is adjustable from 0.4ºF to 2.0ºF
Cooling is adjustable from 0.4ºF to 2.0ºF
18 to 30 VAC, NEC Class II, 50/60 Hz for hardwire (common wire)
Battery power from 2 AA Alkaline Energizer batteries
32ºF to +105ºF (0º to +41ºC)
90% non-condensing maximum
4.7”W x 4.4”H x 1.1”D
13
SPECIFICATIONS & CONTACT INFORMATION
Specifications
Pro1 IAQ Inc.
1111 S. Glenstone
Suite 2-100
Springeld, MO 65804
Toll-free: 1-888-Pro1iaq (776-1427)
Toll Number (Outside the USA): 330-821-3600
Web: http://www.pro1iaq.com
Hours of Operation: Monday - Friday 9 AM - 6 PM Eastern