What does c-wire required mean?

This unit works fine on my circa 1998 central air furnace/AC using G,W,Y,R wires only, so the C wire is definitely not required. My guess is if you have a C-wire, it powers the thermostat while on the wall, and the 3 AAA power it if you pull it off the wall to program it (not necessary as you can program it on the wall). If you don't have a C-wire, then the 3 AAA power it all the time. Net effect: you'll change AAA batteries more often without a C-wire. Again, just a guess, but C-wire definitely not required for this unit to work. This unit also has a lithium battery, likely for its real time clock. You activate it when you pull off the little tab during installation.

does this unit work without a c wire?

Hi Randy! The RTH8500D does not require a C wire. There will be 2 scenarios that the C wire will be required. 1. If the thermostat that will be installed is a Wi-Fi thermostat. 2. If the thermostat that will be installed is a RedLink thermostat and a accessory will be pared to it. -John

Can you dim or turn off the backlight?

Are you asking if the backlight can be turned off when you're actively using the keypad? In my installation, the backlight only comes on when there's activity on the keypad and shuts off shortly after changes are complete. Without the backlight, I can't see the text on the display well enough to change any settings. I'm not aware of a setting that turns of the backlight entirely.

Will the honeywell thp9045a1023 wiresaver work with this thermostat?

Sorry not familiar with the wire saver. Do not know if it will work or not.

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Honeywell RTH8500D 7-Day Touchscreen Programmable Thermostat, "C" Wire Required, White, 1Package (Thermostat) (RTH8500D1013/E1)

Honeywell RTH8500D 7-Day Touchscreen Programmable Thermostat, "C" Wire Required, White, 1Package (Thermostat) (RTH8500D1013/E1)

Product ID: 1628911

Details

Brand
Honeywell
Color
White
Controller Type
Touchpad
Model Name
RTH8500D
Special Feature
Programmable

⚡Smart Response energy saver

📅7-day programmable schedule

🌡️±1°F precise temp control

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Description

🌟 Upgrade your comfort game with smart precision and effortless control!

POWER OUTAGE MEMORY - Never lose your settings thanks to built-in program retention during outages.
UNIVERSAL COMPATIBILITY - Works seamlessly with conventional and heat pump systems up to 2H/2C — one thermostat for nearly every home.
SMART RESPONSE TECHNOLOGY - Learns your system’s timing to deliver perfect temperature just when you need it.
TAILORED COMFORT EVERY DAY - Customize your week with 4 daily periods for ultimate control and convenience.
INTUITIVE TOUCHSCREEN INTERFACE - Large backlit display with easy touch controls keeps you in command, even from your sofa.

The Honeywell RTH8500D is a sleek, 7-day touchscreen programmable thermostat designed for professional-grade comfort and energy efficiency. Compatible with a wide range of heating and cooling systems, it features precise ±1°F temperature control, Smart Response technology that adapts to your home’s needs, and retains programming through power outages. Its intuitive touchscreen and customizable daily schedules empower you to optimize comfort and savings effortlessly.

Specifications

ASIN	B0026ES9UQ
Additional Features	Programmable
Best Sellers Rank	#448,266 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #521 in Home Programmable Thermostats
Brand Name	Honeywell
Color	White
Control Method	Touch
Control Type	Touchpad Control
Controller Type	Touchpad Control
Customer Reviews	4.4 4.4 out of 5 stars (1,592)
Display Type	Digital
Global Trade Identification Number	00783961592196
Included Components	sdfsd
Item Type Name	Honeywell RTH8500D 7-Day Touchscreen Programmable Thermostat, "C" Wire Required
Item Weight	1 g
Manufacturer	Honeywell
Manufacturer Part Number	RTH8500D
Manufacturer Warranty Description	1 year.
Material Type	Plastic
Model Name	RTH8500D
Model Number	RTH8500D1013/E1
Number of Batteries	1 CR2 batteries required.
Number of Items	1
Number of Packs	1
Power Source	Battery Powered
Product Style	Touchscreen,Smart
Screen Size	1 centimeters
Shape	Curved
Specific Uses For Product	Heat Pump
Specification Met	Energy Saving Thermostat
Temperature Control Type	Heating and Cooling
UPC	783961592196 085267256865
Unit Count	1 Count
Voltage	32 volts
Wattage	1 Microwatts

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₨324493

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In stock

Sold byAmazon Sri LankaDelivered byDesertcartCustomer service byDesertcartReturns14 days · 30 with PRO

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Desertcart purchases this item on your behalf and handles shipping, customs, and support to Sri Lanka.

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