Robertshaw 8405 User manual

DIGITAL
NON-PROGRAMMABLE
THERMOSTAT
8405
ELECTRIC
E
GAS
G
OIL
O
®
NeW
1 Heat
User's Manual
Quick Start
Installation
MILLIVOLT
M
Application
The Robertshaw 8405 is a single-stage thermostat designed to control
24 VAC gas or electric heating or millivolt HVAC systems.
Features
• Low battery indicator
• Large backlit display
• Adjustable temperature differential: 1°F to 3.0°F (0.5°C to 1.5°C)
• Accuracy within ±1°
• Zone system compatible as a master thermostat
• Permanent memory retention
• Fahrenheit/Celsius display option
• Adjustable from 45°F to 90°F (7°C - 32°C)
• Quick wire terminal block
• Low temperature freeze protection. While in heat mode, the
thermostat will mechanically turn on the heat if the temperature
drops to 40°F (4°C) – even if the batteries are drained or missing.
1
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WARNING:
• Always turn off power at main fuse or circuit breaker panel before
installing, removing, cleaning, or servicing thermostat.
• Read all the information in this manual before installing this thermostat.
• DO NOT CONNECT TO 120 VAC. This is a 24 VAC low-voltage
thermostat. Do not install on voltages higher than 30 VAC.
• All wiring must conform to local and national building and electrical
codes and ordinances.
• Do not short (jumper) across terminals on the gas valve or at the
system control to test installation. This will damage the thermostat
and void the warranty.
• Do not connect ground to any terminal in this unit.
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 Controls Americas or a local recycling center for proper
disposal. If you have any questions, call Robertshaw technical
support at 1-800-445-8299.
Invensys Controls Americas
28C Leigh Fisher Blvd.
El Paso, TX 79906
Attn: Mercury Recycling Center
Step 1: Replacing Existing Thermostat
Wiring Table
Old Terminal New Label Description
M,W,Rh,R5 or 5 Rh Heat transformer, hot side
V or Rc Rc Cool transformer, hot side
H,W, or 4 W1 Heating control
F or G G Fan control relay
2
!
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1. Turn off power to heating system.
2. Remove cover from old thermostat to expose wires (Figure 1).
3. Disconnect wires one at a time from existing terminals. Use enclosed
labels to mark existing wires. Refer to cross references in the Wiring Table
if existing wiring does not directly match the labels.
4. Remove existing thermostat base from wall.
Step 2: Installing Model 8405 Thermostat
NOTE: FOR NEW INSTALLATIONS, MOUNT THERMOSTAT ON
INSIDE WALL, FIVE FEET ABOVE THE FLOOR. DO NOT
INSTALL BEHIND A DOOR, IN A CORNER, NEAR AIR
VENTS, IN DIRECT SUNLIGHT, OR NEAR ANY HEAT OR
STEAM GENERATING FIXTURES. INSTALLATION AT THESE
LOCATIONS WILL AFFECT THERMOSTAT OPERATION.
1. Turn power off to the heating and cooling systems.
2. Place HEAT-OFF in OFF position (Figure 2).
3. Place AUTO-ON switch into AUTO position (Figure 2).
3
Figure 1
heat off auto on
°
F
Figure 2
heat off auto on
°
F
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4. Remove the cover using a coin or screwdriver (Figure 3). Set aside.
5. Place thermostat against the wall at desired location. Make sure
wires will feed through opening (Figure 4) on base of thermostat.
6. Mark placement of mounting holes (Figure 4). Set base aside.
7. If mounting on drywall, tap plastic anchors into wall.
NOTE: Enclosed plastic anchors do not require a drilled hole
for drywall.
8. If mounting on a surface other than drywall, drill the marked holes
using a 3/16" (5mm) drill bit.
9. Align base with plastic anchors and feed wires through opening.
10. Secure base to wall with supplied screws. NOTE: The thermostat
will mount horizontally on a single gang junction box.
11. Strip end of wires 5/16” (8mm) if needed.
12. Terminal screws are already loose and ready for wire insertion.
Insert wires into terminal strip (Figure 4) matching the label to the
corresponding terminal (see Wiring Diagrams). Tighten screws.
4
heat off cool
hold
vac
prog
run/set hold
temp
clock
set
auto on
MON
°
F
Figure 3
RC
RH
GOB Y1W1
ELEC GAS
°
F
+
–
+
–
Figure 4
Mounting Holes
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5
Hot
Heating
Control
Transformer
24 VAC
120 VAC
HEAT ONLY
SINGLE TRANSFORMER
2-WIRE
RH
RC
W1
G
Factory-Installed
Jumper
T
H
E
R
M
O
S
T
A
T
Hot
Heating
Control
Fan
Control
Transformer
24 VAC
120 VAC
HEAT ONLY
SINGLE TRANSFORMER
3-WIRE
RH
RC
W1
G
Factory-Installed
Jumper
T
H
E
R
M
O
S
T
A
T
Pilot
Generator
Gas valve
TT
250-750
SYSTEM
MILLIVOLT
RH
RC
W1
G
Factory-Installed
Jumper
T
H
E
R
M
O
S
T
A
T
PP
TT
PP
♦Wiring Diagrams
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13. Make sure wire connections are secure.
14. Push excess wire back through opening.
15. Set the Electric/Gas switch to either GAS for a gas/oil heating
system or ELEC for an electric/millivolt heating system (Figure 5).
16. Install two AA Energizer®brand batteries or equivalent into
battery compartment as shown (Figure 5).
17. Replace thermostat cover by snapping into place.
6
RC
RH
GOB Y1W1
ELEC GAS
°
F
+
–
+
–
Figure 5
TERMINAL LEGEND - 8405
TERM EQUIPMENT TO CONNECT REQ? TERMINAL FUNCTION
Rh 24VAC hot connection Yes For input of 24VAC hot
side of heat transformer
Rc 24VAC hot connection Yes For input of 24VAC hot
side of cool transformer
W1 Heat connection Yes* Energizes on a call for
heating
G Indoor fan connection Yes Energizes with Y1 & W1
terminals or with FAN
option switched to the
ON position
Correct battery
placement
ELECTRIC/GAS SWITCH
Selects fan control.
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7
Step 3: Testing the Thermostat
WARNING: DO NOT SHORT (JUMPER) ACROSS TERMINALS OF GAS
VALVE OR SYSTEM CONTROL TO TEST OPERATION. THIS WILL
DAMAGE THE THERMOSTAT AND VOID YOUR WARRANTY.
1. Put the HEAT-OFF switch into the HEAT position.
The will be displayed.
2. Press the button until the temperature setting is at least 3
degrees above room temperature. The heating system should turn
on. The fan may not turn on immediately, depending on the fan
delay built into the furnace.
3. Put the HEAT-OFF switch into the OFF position.
The heating system should turn off. The fan may
continue to run for a short period of time.
4. Put the AUTO-ON switch into the ON position.
The blower fan should turn on.
The display will show a .
5. Put the AUTO-ON switch into the AUTO
position. The blower fan should turn off.
heat off
!
heat off
auto on
auto on
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Step 4: Customizing the Thermostat
♦Settings
System
Off: The heating and cooling systems are off.
Heat: The thermostat controls the heat.
Fan
Auto: Equipment controls the fan.
On: The fan operates continuously.
♦Temperature Differential
The temperature differential is factory set at 1.0°F (.5°C). This means that
whenever the room temperature changes by one degree Fahrenheit
from the temperature setting, the system will turn on. If the system turns
on too often, increase the temperature differential.
♦Changing Fahrenheit (°F) to Celsius (°C),
the Temperature Differential, and
the Filter Monitor
1. The thermostat is preset to display the
temperature in degrees Fahrenheit (US
models) or degrees Celsius (Canadian
models). The temperature display can be
changed. Press and hold both the
and buttons for three seconds. The display will flash either an F
or C. Release buttons. Press the or button to switch the display.
2. Wait five seconds or press and the display will switch to the
differential setting.
3. The display will read diFF. The tempera-
ture differential is factory set at 1.0°F
(0.5°C). Press the or button to adjust
the differential up or down.
4. Wait five seconds or press and the
display will switch to the
filter monitor setting.
5. CHECK FILTER and the length of hours for
the filter monitor will be displayed.
6. Use the or to adjust the filter timer
from 0 (OFF) to 9900 hours. NOTE: The
filter timer is based on equipment run
time. Select the length of time based on
the recommended service interval for
your filter.
7. Press the to return to normal operation.
8
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9
♦Check Filter Reset
Once the filter timer has expired,
CHECK FILTER will turn on and stay
on. To clear the message and reset
the timer:
1. Press the and buttons and
hold for 3 seconds. CLr will appear
in the time display.
2. Press any key to clear the message.
The display will transition to the
temperature scale display as
described in the previous section.
3. No further input is needed. Within a few seconds, the display will
return to the normal operating mode.
♦Backlit Display
This thermostat is equipped with a backlight to make night time temper-
ature adjustments quick and easy. Press the button to activate the
backlight. The backlight will turn off after about 10 seconds of inactivity.
♦Reset
To reset the thermostat press the RESET button located above the upper
left corner of the display.
RC
RH
GOB Y1W1
ELEC GAS
°
F
+
–
+
–
RESET BUTTON
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Step 5: Troubleshooting
Symptom Remedy
Thermostat does not turn on system. Check wiring (see Installation
section).
10
Thermostat turns system on and
off too frequently.
Increase temperature differential
(see Changing the Temperature
Differential section).
Display is blank, flashing or
constant LO BATT.
Replace batteries.
System fan does not operate
properly.
Move Electric/Gas switch to
either electric or gas, to match
system (see Installation section).
Thermostat does not display
proper room temperature.
Check F/C (Fahrenheit/Celsius)
setting. See Changing Fahrenheit
(F) to Celsius (C).
Note: Although the thermostat has a low battery indicator, replace the
batteries once a year to prevent leakage and to prevent the ther-
mostat and heat/cooling system from shutting down due to lack
of battery power in the thermostat.
If problems with thermostat cannot be resolved, call:
Technical Support: [phone]
Monday-Friday 7:30 AM - 5:30 PM CST
For after hours service, a 24-hour automated help line is available.
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