Bryant PREFERREDT A07044 User manual

Installation Instructions
T6--PRH, T6--NRH
PREFERREDtSERIES
THERMIDISTAT
A07045 A07044
Programmable Control Non---Programmable Control
NOTE: Read the entire instruction manual before starting the installation.

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TABLE OF CONTENTS
PAGE
SAFETY CONSIDERATIONS 2....................................
INTRODUCTION 3..............................................
INSTALLATION CONSIDERATIONS 4..............................
INSTALLATION 8...............................................
SYSTEM START--UP AND CHECKOUT 40..........................
OPERATIONAL INFORMATION 51................................
TROUBLESHOOTING 54.........................................
WIRING DIAGRAMS 58..........................................
THERMIDISTAT CONFIGURATION RECORD 78.....................
SAFETY CONSIDERATIONS
Read and follow manufacturer instructions carefully. Follow all local electrical
codes during installation. All wiring must conform to local and national electrical
codes. Improper wiring or installation may damage ThermidistattControl.
Recognize safety information. This is the safety--alert symbol . When you see
this symbol on the equipment and in the instruction manual, be alert to the
potential for personal injury.
Understand the signal words DANGER,WARNING,andCAUTION.These
words are used with the safety--alert symbol. DANGER identifies the most
serious hazards which will result in severe personal injury or death. WARNING
signifies a hazard which could result in personal injury or death. CAUTION is
used to identify unsafe practices which may result in minor personal injury or
product and property damage. NOTE is used to highlight suggestions which will
result in enhanced installation, reliability, or operation.

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INTRODUCTION
Bryant’s 7--day, 5/2--day, 1--day programmable and non--programmable
Preferred Series Thermidistat Control is a wall--mounted, low--voltage control
which combines temperature and humidity control in either a single unit or a
two--piece unit. In two--piece configuration, the relays are located near the
equipment and a two--wire connection is used between the Display Module and
the Equipment Control Module. Single--piece installation requires more wiring
and results in a higher profile. The Preferred Series Thermidistat has no need for
batteries to store user--configured settings in memory. During power loss its
internal memory saves settings for unlimited time, and the clock continues to run
for at least 24 hours. An extension of Bryant’s proven line of thermostats; it
provides separate setpoints for heating and cooling in addition to humidification
and dehumidification.
In the Preferred Series Thermidistat Control’s programmable configuration,
different heating and cooling setpoints and times are programmable for 4 periods
per day or 2 periods per day. Programming can be done for 7 days per week, 5/2
days per week, or 1 day. The programmable Thermidistat Control can also be
user configured as a non--programmable Thermidistat Control. When operating
as non--programmable, the Thermidistat Control will still have both temperature
and humidity control.
The non--programmable Thermidistat Control features Touch ’N’ Gotsettings
for quick and easy temperature change without complicated programming
schedules. The non--programmable Thermidistat Control will still have both
temperature and humidity control. And, its Touch ’N’ Go technology enables the
user to switch between three different user--configurable settings through
intuitive buttons located just below the display.

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INSTALLATION CONSIDERATIONS
Power
This control is powered by 24VAC only. It requires 24VAC (Rh and/or Rc and C
terminals) of the low--voltage transformer to be connected to it for proper
operation. It will not operate without these 2 connections. Rh and Rc are
connected via PCB breakout jumper. See Fig. 1. For applications using two
24VAC transformers, one in the indoor unit and one in the outdoor unit, connect
the common from each to the C terminal. Connect R from the indoor unit to the
Rh terminal. Connect R from the outdoor unit to the Rc terminal. Then, break
jumper on the circuit board. The W and HUM signals are taken from the Rh
power and the G signal is taken from the Rc power. If Thermidistat Control has
been installed in a two--transformer application that is later changed to a
single--transformer installation, installer must install a field supplied jumper
between Rc and Rh. Depending on the installation, up to 14 wires may be
required. Installation as two--piece unit is recommended. Only 2 wires are
required for connection between Display Module and Equipment Control
Module. These two wires (V+ and Vg) do not provide ordinary 24VAC. They
carry a combination of power and communications data that is unique to these
products.

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A07052
Fig. 1 -- PCB Breakout Jumper
Models
There are programmable and non--programmable models for all applications.
They can be configured for AC or HP, 1--or 2--speed compressor, and for Hybrid
Heattinstallations, allowing it to be used in place of all Bryant thermostats.
Programmable Thermidistat Controls may be configured as non--programmable
if user desires.
Humidify Equipment and Connections
The humidify output connects directly to 24VAC operated humidifiers. No other
connection or interlock is required. Any of several installer--selectable operating
modes are available.

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ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury or death.
DO NOT connect furnace HUM terminal directly to Thermidistat Control
HUM terminal. This will bypass furnace safety controls. See Low Voltage
Wiring Diagrams and notes for proper connection.
!WARNING
Dehumidify Equipment and Connections
The dry contact output connects to the dehumidify input on variable--speed
furnaces and fan coils. Additional dehumidification is done by controlling the
compressor. A variety of operating modes are available. The dry contact must be
configured for dehumidification in setup Option 19. See Wiring Diagrams for
more information.
Outdoor Temperature Sensor
Outdoor air temperature sensor is included in the box with the Thermidistat
Control. Optimum performance is obtained when an outdoor temperature sensor
is used with the Thermidistat Control. Plan installation so that 2 wires can be run
from Equipment Control Module to an outdoor location, preferably on the north
side of the house or refer to Installation Instructions included with the outdoor
temperature sensor for simplified connection. Sensor can be mounted to outdoor
unit and existing control wires may be used for its connection. Details are
provided in sensor instructions.

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Remote Indoor Temperature Sensor
A remote temperature sensor may be used with the programmable model, where
it is desirable to install the Thermidistat Control in a limited access location while
measuring the temperature in the living space. The remote room sensor may be
used as a stand alone or average with local sensor.
Two--Piece Thermidistat Configuration
The Preferred Series Thermidistat Control can be installed in one of two
configurations. The control may be installed as a single--piece Thermidistat or it
may be split into two pieces and mounted in separate locations. As a single--piece
unit, all required wiring must be brought to the Equipment Control Module for
connection to the terminal strip. In two--piece configuration, the Display Module
can be mounted in the living space while the Equipment Control Module may be
mounted near the indoor furnace or fan coil. Connection from the display to the
Equipment Control Module requires only two wires. All other control wires are
connected to the Equipment Control Module from the HVAC equipment. This
configuration results in a slimmer display and locates the Equipment Control
Module containing the switching relays away from the main living space where
relay clicking will not be heard.

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INSTALLATION
Carton contains the following components. See Fig. 2 for T6--PRH or Fig. 3 for
T6--NRH.
A07752
Fig. 2 -- T6--PRH Carton Contents
1. Display Module
2. Stand--off for Equipment Control Module
3. Outside Air Temperature Sensor, screws and pigtail.
4. Equipment Control Module

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A07753
Fig. 3 -- T6--NRH Carton Contents
1. Display Module
2. Stand--off for Equipment Control Module
3. Outside Air Temperature Sensor, screws and pigtail.
4. Equipment Control Module
Thermidistat Control Location
Thermidistat Control should be mounted:
SApproximately 5 ft (1.5m) from floor.
SClose to or in a frequently used room, preferably on an inside parti-
tioning wall.
SOn a section of wall without pipes or duct work.
Thermidistat Control should NOT be mounted:
SClose to a window, on an outside wall, or next to a door leading to the
outside.

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SExposed to direct light or heat from a lamp, sun, fireplace, or other
temperature--radiating objects which could cause a false reading.
SClose to or in direct airflow from supply registers and return--air regis-
ters.
SIn areas with poor air circulation, such as behind a door or in an al-
cove.
Installer should determine whether control will be installed as single--piece or
two--piece. In single--piece configuration, as many as 14 wires may need to run
to wall mounting location for connection to the control. In two--piece
configuration, the Display Module and Equipment Control Module are
connected by two wires.
Install Thermidistat Control
ELECTRICAL OPERATION HAZARD
Failure to follow this warning could result in personal injury
or death.
Before installing Thermidistat Control, turn off all power to
equipment. There may be more than 1 power disconnect.
!WARNING

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UNIT DAMAGE HAZARD
Failure to follow this caution may result in equipment damage
or improper operation.
Improper wiring or installation may damage Thermidistat
Control. Check to make sure wiring is correct before
proceeding with installation or turning on power.
CAUTION
!
1. Turn off all power to equipment.
2. If an existing Thermidistat Control is being replaced
a. Remove existing control from wall.
b. Disconnect wires from existing control, 1 at a time.
c. As each wire is disconnected, record wire color and terminal marking.
d. New or additional wire may be needed to accommodate added hu-
midity outputs.
e. Discard or recycle old control.

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ENVIRONMENTAL HAZARD
Failure to follow this caution may result in environmental
damage.
Mercury is a hazardous waste. Federal regulations require that
Mercury be disposed of properly.
CAUTION
!
Two--Piece Installation
The following steps should be followed for the installation of the two--piece
configuration.
NOTE: The 2--wire pigtail is not intended to support the weight of the User
Interface. Do not hang the User Interface from the Equipment Control Module
screw terminals.
1. Remove mounting plate from back of Display Module by pressing the
two tabs on the bottom edge and pulling away. See Fig. 4 and 5.

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A07225
Fig. 4 -- Press Tabs to Remove Backplate
A07226
Fig. 5 -- Take Apart

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2. Route wires through large hole in mounting base. Level mounting base
against wall (for aesthetic value only—Display Module need not be lev-
eled for proper operation) and mark wall through 2 mounting holes. See
Fig. 6.
A07165
Fig. 6 -- Backplate Mounting
3. Drill two 3/16--in. mounting holes in wall where marked. Thermidistat
may be mounted to a standard junction box, if desired. Hole pattern on
Thermidistat Control mounting base matches junction box mounting
holes.
4. Secure rear plastic mounting base to wall with 2 screws and anchors pro-
vided. Additional mounting holes are available for more secure mounting
if needed. Make sure all wires extend through hole in mounting base.
5. Adjust length and routing of each wire to reach proper connector block
and terminal on mounting base with 1/4--in. extra wire.

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6. Match and connect equipment wires to proper terminals of each connector
block, being careful not to over tighten the screws. Correct polarity must
be observed when connecting the two wires from the Equipment Control
Module to the Thermidistat Control mounting base. If wires are con-
nected incorrectly, the Display Module will not operate. See Fig. 7, 8 and
9.
Relays
OAT
RRS
SRTN
HUM
D1
D2
V+
Vg
Rc
Rh
W / W1
G
Y/Y2
Y used for
single stage
cooling
C
O/W2/B
Y1
Y1 used for
multi-speed
cooling
Y1 = stage 1
Y2 = stage 2
Control Module Wiring Guide
connect
to user
interface
dry
contact
OAT /
RRS
return
{
Relays
OAT
RRS
SRTN
HUM
D1
D2
V+
Vg
Rc
Rh
W / W1
G
Y/Y2
Y used for
single stage
cooling
C
O/W2/B
Y1
Y1 used for
multi-speed
cooling
Y1 = stage 1
Y2 = stage 2
Control Module Wiring Guide
connect
to user
interface
dry
contact
OAT /
RRS
return
{
A07687
Fig. 7 -- Control Module Wiring Guide
SRed is V+
SBlack is Vg

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A07166
Fig. 8 -- Secure Wires to Terminal Strip
A07167
Fig. 9 -- Connect Pigtail Wires to Display Module

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NOTE: The 2--wire pigtail is not intended to support the weight of the User
Interface. Do not hang the User Interface from the Equipment Control Module
screw terminals.
SRed of the pigtail is V+
SBlack of the pigtail is Vg
7. Push any excess wire into wall and against mounting base. Seal hole in
wall to prevent air leaks. Leaks can affect operation and cause incorrect
temperature and/or humidity measurement.
8. Make sure 2--wire pigtail is attached to Display Module mounting base.
This should come attached from the factory. Attach two--wire pigtail to
the back of the Display Module via 2 pin, keyed connector.
9. Reattach Display Module body to mounting base by first setting on at top
of mounting base and then push bottom corners of Display Module to
snap into place. See Fig. 10.
A07169
Fig. 10 -- Attach Display to Backplate

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10. Find suitable indoor mounting location for Equipment Control Module,
either near or on equipment. See Fig. 11.
IMPORTANT NOTE: Equipment Control Module should not be mounted
to duct work or below any other controls or equipment (i.e. humidistat,
humidifier, etc.).
A07217
Fig. 11 -- Equipment Control Module on Equipment
11. Route wires through rear of Equipment Control Module using either a
clearance hole or supplied standoff. See Fig. 12.

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A07227
Fig. 12 -- Standoff
12. Match and connect equipment wires to proper terminals of each connector
block being careful not to over tighten the screws. Correct polarity must
be observed when connecting the two wires from the Equipment Control
Module to the Thermidistat Control mounting base. If wires are con-
nected incorrectly, the Display Module will not operate. See Fig. 7, 8 and
9.
13. Snap cover over top of Equipment Control Module. See Fig. 13.

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A07218
Fig. 13 -- Cover on Equipment Control Module
14. Turn on power to equipment. On power up, all display segments will
light for 5 sec. For the next 5 sec a 2--digit code appears on large display
which identifies Thermidistat Control configuration. Refer to Option 33.
a. AC — 1--stage air conditioner
b. HP — 1--stage heat pump
c. A2 — 2--stage air conditioner
d. H2 — 2--stage heat pump
e. hh — Hybrid Heat system with 1--stage heat pump
f. h2 — Hybrid Heat system with 2--stage heat pump
g. H — heating only system
h. C — cooling only system