Digital Thermostat
Owners Manual
Model: HC7174SB
Your new thermostat will provide years of reliable service. Using this
digital thermostat will provide more uniform comfort in your home through
the seasons. Thank you for buying the product!
Please read this manual for complete instructions on installing and
operating your thermostat. If you require further assistance, please feel
free to contact us.
IMPORTANT INFORMATION
1. This thermostat is designed to work on the following systems:
Gas – Standing Pilot
Oil – Fired Furnace
Gas – Electronic Ignition
Single Stage Heat Pumps – with no
Gas – Fired Boilers
auxiliary heat
Gas – Milivolt Systems
Electric Furnace
Oil – Fired Boilers
Electric Air Conditioning
This thermostat will NOT control multistage heat pumps or 110/220V
baseboard electric heating systems.
2. Temperature Range
This thermostat can be set between 45˚F and 95˚F (7˚C and 35˚C).
However, it will display room temperatures from 30˚F to 99˚F (0˚C and
37˚C). "HI" will be displayed if the temperature is higher than 99˚F (37˚C),
and "LO" will be displayed if the temperature is lower than 30˚F (0˚C).
This thermostat will automatically cutoff in Heat mode if the temperature
rises above 71˚F (22˚C), and automatically cutoff in Cool mode if the
temperature drops below 74˚F (24˚C).
3. Compressor Protection
This thermostat provides a 4 minute delay after shutting off the compressor
before it can be restarted. This feature will prevent damage to your
compressor caused by rapid cycling. It does not prevent a rapid
compressor restart due to short power outages.
4. Battery Warning
Two fresh AA alkaline batteries should provide well about one year of
service. However, when the batteries become drained the Low Battery
Indicator will flash on the display. When this message occurs, install new
alkaline batteries. You have approximately 1 minute to change the batteries
and keep the thermostat's settings. Once the batteries have become too
low to ensure proper operation, your system will be turned off, and the
display will be cleared except for flashing Low Battery Indicator on the LCD
display.
CAUTION: When only the battery icon flashes on the display, the
thermostat is shut down, and your system will no longer operate. In this
condition, there is no temperature control of your dwelling.
NOTE: The backlight will not function when the thermostat is in low battery
condition.
NOTE: If you plan to be away from the premises over 30 days, we
recommend that you replace the old batteries with new alkaline batteries
prior to leaving.
5.Power supply
The thermostat shall be powered by 24 VAC and with batteries as backup.
FEATURES
Structure of thermostat and explanation for the keypads
Light: Backlight display automatically
Low Battery Indicator. Flashes when
with each key press for easy viewing.
batteries need to be replaced.
Filter Change
Indicator:Flashes
when filter needs
to be checked.
LCD Display:
Shows Room
Temperature,Set
Temperature,and
other feature
SYSTEM
information as
required.
COOL
OFF
HEAT
Front Door:
Cover keys Open with one finger from left or right.
OPERATION
Start-up
The LCD will show the factory default display
of 70˚F (21˚C) when batteries are first
installed,. The temperature will update after a
few seconds.
System Selector Switch
system
cool
off
heat
NOTE: Anytime you install or remove the thermostat from the wallplate,
slide the System Selector to the OFF position to prevent the possibility of a
rapid system On – OFF.
Fan Switch
system
fan
auto
cool
heat
on
off
warm-up delay. For electric heat, air conditioning, and heat pump operation,
the Fan will turn on with the system.
To run the Fan on continuously, slide the Fan switch to the ON position.
Review Current Set Temperature
Press either the up or down key once to see the Set Temperature.
The factory default is 68˚F (20˚C) when started with the System Switch Off
or Heat, and 78˚F (26˚C) when started with the System Switch on Cool.
Setting New Temperature
Press either the up or down once and
display the set temperature.
Press either up or down again to change to
your desired Set Temperature. Hold the key
down for over 2 seconds to fast advance the
Set Temperature.
The display will return to the normal room temperature after the keys have
been released for 5 seconds.
NOTE: No matter how you set the heating temperature value under the
heating mode, the setting temperature will be re-set to 68℉automatically
after 3 hours.
Filter Monitor
The thermostat counts the number of hours
your system's filter has been in use. To
maximize your system's performance and
energy efficiency, change or clean your filter
regularly. When the total system run time for
heat and cool reaches 400 hours, the Filter Change Indicator will flash as a
reminder to check your system's filter.
After changing or cleaning the system filter, press and hold the Filter key
for 3 seconds. The display will blink, and the counter will be reset to zero.
Note: Pressing the Filter key at any time for less than 3 seconds will cause
the Filter Change Indicator to appear on the LCD. This is only to confirm
key operation, and the counter is not affected unless the key is held for
greater than 3 seconds.
SPAN Setting
Your thermostat is set at the factory to cycle at 2˚F (1˚C) above and below
the set temperature. (Span = 2) This setting has been designed to provide
a comfortable room temperature under most all conditions. However, if you
find your system cycling too fast or too slow, then the Span can be adjusted
to modify the cycle time.
Press down to lower the Span to 1. This setting DECREASES the cycle
time by causing your system to run SHORTER.
Filter Key:
Resets the
The Span settings remain the same for both HEAT and COOL, and can be
filter change
counter to zero.
changed in any System Switch position.
Up and Down Keys:
Keys for changing
the Temperature
When batteries are installed in the thermostat, the Span is reset back to
setting. Also used
for adjusting the
Span.
setting 2.
FAN
Fan Switch: Fan
switch for Automatic
Backlighting
or Continuous fan
ON
AUTO
operation.
System switch:
Your thermostat has an electroluminescent lamp that backlights the display
selector switch for
Heat,Cool,and Off.
for easy viewing in the dark.
When any key is pressed, the display is illuminated.
The display will remain illuminated for 7 seconds after the last key is
pressed. This allows the light to stay on if you need to operate several
TEMP
fan
The System Selector switch on the front of the
thermostat determines the operating mode of the
on
auto
thermostat. You may select COOL, OFF, HEAT.
The Fan switch should normally be located in the AUTO
position. The Fan will be turned on along with normal
operation of your system. In a normal gas or oil furnace,
the Fan will be turned on by your furnace after its
SET
TEMP
Press and hold BOTH up and down keys for three
seconds. SPAN will be displayed on the LCD.
Press up to raise the Span to 3. This setting
INCREASES to cycle time by allowing your system
to run LONGER.
keys.
Note: If the thermostat is in Low Battery warning condition, the backlight
will not operate. Replace with 2 new AA alkaline batteries to restore the
Backlight function.
Low Battery Warning
Your thermostat has a two-stage lower
battery
warning
system.
When
the
batteries are first detected to be weak, the
first stage low battery warning is indicated
by battery symbol flashing on the LCD
display. At your earliest convenience, you
need to replace the batteries with 2 new AA alkaline batteries. When the
batteries become too weak for normal operation, the thermostat enters the
second stage low battery warning which shuts down the
this condition, battery symbol flashes alone on the display, and the
thermostat will turn your system off. Your system will remain shut-off until
the batteries are replaced.
Note: The thermostat will still keep the current Set Temperature and Filter
run time in memory until new batteries are installed. After confirming that
new batteries have been inserted, the thermostat will return to normal
operating .
Error Mode
If the thermostat is unable to control your
system due to an unexpected battery
problem, the thermostat will enter Error
Mode. In this condition, the thermostat
flashes "E1"or "E2" on the LCD display, and
shuts off your system.
To correct this problem, replace the batteries with 2 new AA alkaline
batteries, even if you have recently
replaced them. Next, Move the battery out
hold any key then place the battery again.
You will need to reprogram your thermostat
and confirm normal operation. If Error
Mode returns, please call us for further
information.
Lcd display
information
Lcd display
E1
Sensor Error
E2
Auto Cut Off
Your thermostat will automatically cutoff in Heat mode if the room
temperature rises above 71˚F (22˚C). It will cutoff in Cool mode if the room
temperature drops below 74˚F (24˚C).
Note that if your system has malfunctioned and no longer responds to
thermostat controls, the Auto Cut-Off will have no effect.
INSTALLATION
What You Need
This thermostat includes two #8 slotted screws and two wall anchors for
mounting. To install your thermostat, you should have the following tools
and materials.
Slotted Screwdriver(s)
Small Philips screwdriver
Hammer
Electric drill and 3/16" bit
Two 1.5V (AA) size alkaline batteries (included)
Remove Old Thermostat
CAUTION: Do not remove any wiring from existing thermostat before
reading the instructions carefully. Wires must be labeled prior to
removal.
INPORTANT! Turn off the power to the furnace at the main power
panel or at the furnace.
Remove existing thermostat cover and thermostat. Some thermostats will
have screws or other locking devices that must first be removed. Once the
wall mounting plate is exposed, look for wires. If wires are not visible, they
may be connected to the back of the wallplate. Again, look for screws, tabs,
etc. Some models have doors that open to expose wires and mounting
screws. See Figure 1.
Typical Home Thermostats
Wall mounting Plate
Thermostat
Wall mounting Plate
Thermostat
Figure 1
Wiring Labeling
Each wire coming from the wall to the existing thermostat is connected to
a terminal point on that thermostat. Each of these terminal points is usually
marked with a code latter as shown in Table A below.
Note that this thermostat has multiple function terminals that allow
Single-Stage Heat Pump capability. Standard systems use: Rh, Rc, G, Y, W.
[Single-Stage Heat Pumps use: R, Y, G, and O or B.] Table A below shows
the multiple functions of the terminals. Use the terminals that match your
SET
TEMP
thermostat. In
information
System switch Error
Cover
Cover
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