Honeywell T8411R Thermostat User Manual

T8411R Electronic

Heat Pump Thermostat

INSTALLATION INSTRUCTIONS

The T8411R Heat Pump Thermostat provides 24V

control of two-stage heating and one-stage cooling heat

pump system with manual changeover from heat to cool.

First stage heating and cooling cycle rates are fixed at

CAUTION

Electrical Shock or Equipment Damage

Hazard.

cph. Second stage heating cycle rate is selectable at

, 4, 5, 6, 9 or 12 cph. Temperature indication can be set

Can shock individuals or short equipment

circuitry.

Disconnect power supply before installation.

for °F or °C.

The T8411R Heat Pump Thermostat is powered directly

from the system transformer. Batteries are not required

because setpoints are held permanently by non-volatile

memory.

Location

Install the thermostat about 5 ft (1.5m) above the floor in

an area with good air circulation at average temperature.

See Fig. 1. Do not install the thermostat where it can be

affected by:

The T8411R includes a thermostat, wallplate (for wiring

and mounting thermostat), and owner’s guide. A 7 3/8 in.

x 5 3/4 in. (188mm x146 mm) decorator cover plate (for

covering wall marks) is available separately. Order

Honeywell part no. 209649A (taupe color).

—

drafts or dead spots behind doors and in corners.

hot or cold air from ducts.

radiant heat from the sun or appliances.

concealed pipes and chimneys.

unheated (uncooled) areas such as an outside wall

behind the thermostat.

MERCURY NOTICE

If this control is replacing a control that contains

mercury in a sealed tube, do not place your old

control in the trash.

This thermostat is a precision instrument and was

carefully adjusted at the factory. Handle it carefully.

Mounting Wallplate to Wall

IMPORTANT

Contact your local waste management authority

for instructions regarding recycling and the

proper disposal of an old control containing

mercury in a sealed tube.

Level only for appearance. The thermostat func-

tions normally even when not level.

Mount wallplate, T8411R and the screws provided (see

Fig. 2) as follows:

INSTALLATION

Place the wallplate at the desired location on the

wall.

Use a pencil to mark the mounting holes.

Remove the wallplate from the wall and drill two

3/16 in. holes in the wall (if drywall) or two 7/32 in.

holes for firmer material such as plaster or wood.

When Installing this Product…

Read these instructions carefully. Failure to follow

them could damage the product or cause a hazard-

ous condition.

Check the ratings given in the instructions and on

the product to make sure the product is suitable for

your application.

Installer must be a trained, experienced service

technician.

After installation is complete, check out product

operation as provided in these instructions.

4. Gently tap the anchors (provided) into the holes

until flush with the wall.

5. Position the wallplate over the holes.

6. Pull the thermostat wire through the wallplate

entrance hole.

7. Fasten the wallplate to the wall using the anchors

and screws provided.

U.S. Registered Trademark

69- 1486- 1

T8411R ELECTRONIC HEAT PUMP THERMOSTAT

YES

FEET

[

1.5 METERS]

M11338

Fig. 1. Typical location of thermostat.

The shape of the terminals permits insertion of straight or

wraparound wiring connections; either method is

acceptable. See Fig. 3.

WALL

ANCHORS (2)

FOR STRAIGHT INSERTION

TERMINAL

SCREW

STRIP 5/16 IN. (8 MM)

FOR WRAPAROUND

STRIP 7/16 IN. (11 MM)

MOUNTING

SCREWS (2)

WALLPLATE

WHEN USING WALL ANCHORS, DRILL 3/16 INCH

HOLES FOR DRYWALL, 7/32 INCH HOLES FOR

PLASTER OR WOOD.

M12202A

Fig. 2. Mounting wallplate to wall.

Wiring

IMPORTANT

Use an 18-gauge maximum wire for wiring the

T8411R Thermostat.

NOT ALL MODELS HAVE BOTH O AND B TERMINALS.

M11334A

All wiring must comply with local electrical codes and

ordinances.

Fig. 3. Wiring connections.

NOTE: To ensure proper mounting of thermostat,

restrict all wiring to the shaded area. See Fig. 4.

CAUTION

Electrical Shock or Equipment Damage

Hazard.

Can shock individuals or short equipment

circuitry.

Disconnect power supply before installation.

9-1486-1

T8411R ELECTRONIC HEAT PUMP THERMOSTAT

Refer to Fig. 5 for typical wiring hookups. A letter code is

located near each terminal for identification.

KEEP WIRING IN

SHADED AREA

Loosen the terminal screws on the wallplate and

connect the system wires. See Fig. 5.

Securely tighten each terminal screw.

Push the excess wire back into the hole.

Plug the hole with nonflammable insulation to pre-

vent drafts from affecting the thermostat.

Mounting Thermostat to Wallplate

Engage the tabs at the top of the thermostat and

wallplate.

Swing down the thermostat and press the lower

edge of the thermostat onto the wallplate to latch.

See Fig. 6.

MOUNTING

SCREW HOLE

WIRING ENTRANCE

HOLE

MOUNTING

SCREW HOLE

NOT ALL MODELS HAVE BOTH O AND B TERMINALS.

M11331A

Fig. 4. Restrict wiring to shaded area.

(HOT)

THERMISTOR

SENSOR

STAGE 2 RELAY

AUXILARY

THERMOSTAT

LOGIC

HEAT RELAY

SYSTEM

SWITCH

RELAY

EM. HT.

HEAT

OFF

CHANGEOVER

VALVE HEAT

COOL

CHANGEOVER

VALVE COOL

STAGE 1 RELAY

COMPRESSOR

CONTACTOR

COMPRESSOR

CONTACTOR

HEAT

EMERGENCY

HEAT RELAY

FAN SWITCH

FAN RELAY

POWER

SUPPLY

AUTO

POWER SUPPLY. PROVIDE DISCONNECT MEANS AND OVERLOAD PROTECTION AS REQUIRED.

REMOVE JUMPER, WHEN SUPPLIED, FOR SYSTEMS WITH SEPARATE HEATING COMPRESSOR CONTACTOR (W1 SEPARATE FROM Y).

NOT ALL MODELS HAVE BOTH O AND B TERMINALS.

M11333A

Fig. 5. T8411R two-stage heat and one-stage cool wiring diagram with manual changeover.

69-1486-1

T8411R ELECTRONIC HEAT PUMP THERMOSTAT

FAN Switch

DASHED LINES INDICATE TABS

ON BACK OF THERMOSTAT

Fan switch settings are:

On: The fan runs continuously. Use for improved air

circulation and air quality.

Auto: Normal setting for most homes. The fan starts

and stops with the equipment.

Em Ht

Aux Ht

Slide the FAN switch in the bottom left corner of the

thermostat to select the desired fan setting.

Set

Room

SYSTEM Switch

System switch settings control thermostat operation as

follows:

Auto

FAN

Cool: The thermostat controls the cooling system.

Off: Both heating and cooling are off.

Cool

YSTEM

eat Em

Heat: The thermostat controls the heating system.

Em Ht: Thermostat cycles auxiliary heat (W2) and

emergency heat relay (E) as needed to maintain

setpoint. Terminal L is energized continuously.

Fault heat relay is on continuously. Cooling system

is off. Compressor is de-energized.

ENGAGE TABS AT TOP OF THERMOSTAT

WITH SLOTS ON MOUNTING PLATE.

Slide the SYSTEM switch in the bottom right corner of

the thermostat to select the desired system setting.

Set

TEMPERATURE DISPLAY

INCREASE SETTING

oom

DECREASE SETTING

FAN

Auto

Em Ht

Aux Ht

Cool O fS YS

Heat Em Ht

Set

Room

Auto On

PRESS LOWER EDGE OF

CASE TO LATCH.

M18541

^C^o^o lS YSTEM

Off

FAN SWITCH

^H^eat Em H_t

Fig. 6. Mounting thermostat wallplate.

SYSTEM SWITCH

M18542

OPERATION

Fig. 7. Digital display and system

switches (FAN and SYSTEM).

Setting FAN and SYSTEM Switches

Em Ht and Aux Ht Indications

Fan and system settings are controlled manually by

using the switches located at the bottom of the

thermostat case. See Fig. 7.

The ▲ indicator points to either Emergency Heat (Em Ht)

or Auxiliary Heat (Aux Ht) when these modes are active.

Em Ht: The ▲ indicator points to Em Ht when the

SYSTEM switch is set at Em Ht.

Aux Ht: The ▲ indicator points to Aux Ht when the

auxiliary backup heat is needed to help handle

the heating load.

INDICATOR

Em Ht

Set

Room

M18425

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T8411R ELECTRONIC HEAT PUMP THERMOSTAT

Press the ▲▲ keys simultaneously for more than

one second to light all segments on display and to

enter installer setup mode. When the keys are

released, a two-digit software revision code is dis-

played.

Set Temperature Setpoint

NOTE: Temperature setpoint range is 40° to 99°F (4° to

39°C).

The temperature setpoint and the room temperature are

shown separately on the digital display. The ▲ indicator

points to Set when the temperature setpoint is displayed

and to Room when the room temperature is displayed

M18426

OPTIONAL SYSTEM CHECKOUT

INDICATOR

When the heat or cool outputs are turned on, the five-

minute off-timer safety feature is bypassed.

ROOM TEMPERATURE

Set

Room

SETPOINT TEMPERATURE

When in steps 2 and 3 only, the ▲ key can be used to

turn heat or cool outputs on and off. Change the

SYSTEM switch setting to test heat or cool outputs. No

action takes place If the system switch is in the Off

position.

M14679

To set temperature setpoint:

Select Heat or Cool by sliding the SYSTEM switch

in the lower right corner of the thermostat to the

desired mode. See Fig. 7.

The following examples of system settings show a two

digit software code on the display. The code shown is

only an example; codes may vary.

To display the temperature setpoint on the digital

display, press either the ▲ or ▲ key once. The

temperature setpoint is displayed for approxi-

mately five seconds as the indicator points to Set

and flashes.

System setting at Heat:

To turn heat on, press the ▲ key.

M14680

M18431

To increase the temperature setpoint press the ▲

key. Each press changes the setpoint one degree;

press and hold to change the setpoint several

degrees.

To turn auxiliary heat on, press the ▲ key.

Aux Ht

M18432

To turn auxiliary heat off, press the ▲ key a third time.

M14681

To decrease the temperature setpoint press the ▲

key. Each press changes the setpoint one degree;

press and hold to change the setpoint several

degrees.

M18433

To turn heat off, press the ▲ key a fourth time.

M14682

M18434

System setting at Cool:

Setting °F/°C Indication and Heat Cycle Rate

To turn cool on, press the ▲ key.

NOTE: To save changes to the °F/°C indication and the

heat cycle rate, all seven steps must be com-

pleted.

M18435

To turn cool off, press the ▲ key.

In installer setup mode, steps 2 through 5, each

press of the ▲ key momentarily displays 01 and

each press of the ▲ key momentarily displays

2. When the keys are released, these two-digit

M18434

codes are no longer displayed.

Press the ▲ key. Factory information is displayed.

A typical example is shown, but information dis-

played varies by model. This information is for fac-

tory use only.

To set the °F/°C indication and heat cycle rate:

If the temperature is displayed in °F, set the tem-

perature setpoint to 52°F. If the room temperature

is displayed in °C, set the temperature setpoint to

Press the ▲ key again to display °C or °F.

11°C.

M14688

M14683

69-1486-1

T8411R ELECTRONIC HEAT PUMP THERMOSTAT

Press the ▲ key to change the °C or °F indication.

10. Press the ▲ key to save all changes, exit installer

setup mode and return to normal operation.

NOTE: After exiting installer setup mode, change the

setpoint to the desired room temperature.

M14689

NOTE: Stage-one heat and cool cycle rates are fixed at

cph. Only stage-two heat cycle rates are

CHECKOUT

selectable.

Press the ▲ key to display the heat cycle rate of 3,

Heating

, 5, 6, 9 or 12. If the desired cycle is displayed,

Slide the SYSTEM switch to Heat and the FAN

switch to Auto.

see Table 1, press the ▲ key to exit the installer

setup mode. To change the heat cycle rate, press

the ▲ key to scroll between 3, 4, 5, 6, 9 and 12.

Stop scrolling when the desired rate is displayed.

Press and hold the ▲ key to raise the temperature

setting several degrees above the room tempera-

ture. After approximately five minutes, the heating

equipment should start.

Press the ▲ key to lower the temperature setting

below the room temperature. Heating equipment

should stop.

M14690

Cooling

Table 1. Heat Cycle Rates.

System

Cycle Per Hour

CAUTION

Operating at too low of an outdoor

temperature may cause compressor damage.

Do not operate cooling if outdoor temperature is

below 50°F (10°C). Refer to manufacturer’s

recommendations.

Hydronic heat, condensing gas

furnace

Equipment Damage Hazard.

Gas or oil forced air

Electric heat

•

For compressor protection, allow the

compressor to remain off for five minutes

before restarting.

_S_p_e_c_i_a_l_a_p_p_l_i_c_a_t_i_o_n_sb

4, 5, 12

High efficiency furnace.

Refer to equipment manufacturer’s instructions.

Slide the SYSTEM switch to Cool and the FAN

switch to Auto.

Press the ▲ key to lower the temperature setting

several degrees below the room temperature. After

approximately five minutes, the cooling equipment

and fan should start.

Press the ▲ key to raise the temperature setting

above the room temperature. Cooling system

should shut down.

Press the ▲ key to display cooling algorithm con-

figuration default.

M18421

Press the ▲ key again to change cooling algorithm

to C1 or C3.

C1 = Standard cooling algorithm.

C3 = Aggressive cooling algorithm (can cause

overshooting).

Press the ▲ key again. Current configuration (CC)

is displayed. A typical example is shown, but CC

varies by model. (This information is for factory use

only.)

Fan

Slide the SYSTEM switch to Off and the FAN

switch to On. The fan should run continuously.

Slide the FAN switch to Auto. The system turns the

fan on and off with the equipment.

Make certain all equipment responds properly to the

thermostat.

M18420

Automation and Control Solutions

Honeywell Honeywell Limited-Honeywell Limitée

985 Douglas Drive North

Golden Valley, MN 55422

35 Dynamic Drive

Scarborough, Ontario

M1V 4Z9

9-1486-1 G.H. Rev. 2-02

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