Question 1

my schedule keeps disappearing or resetting to default on its own. why won't it save my changes?

Accepted Answer

DIAGNOSIS This is usually caused by a brief power interruption that triggers a reboot. Without a properly functioning C-wire, the thermostat relies on its internal memory, which can get corrupted during a brownout or quick power cycle. FIX Confirm your C-wire is providing constant power. Follow the steps for checking the C-wire connection at the thermostat and furnace from the 'blank screen' fix above. A solid C-wire connection is the single biggest factor in schedule and setting stability. Once verified, go to the thermostat and manually re-enter your schedule. Then, perform a manual reboot: pull the display off the wall plate, wait 15 seconds, and snap it back on. See if the schedule sticks after this clean boot. IF THAT DIDN'T WORK There's a system reset that clears all settings and restores factory defaults. Go to Menu > Preferences > Restore Factory Defaults. You'll have to set up Wi-Fi and your schedule again from scratch, but this can clear out corrupted memory that's causing the reset loop. It's a pain, but it often works. HEADS UP If you're making schedule changes in the Total Connect Comfort app, ensure you tap 'Save' or 'Done' and wait for the confirmation. Also, know that if someone changes the schedule directly on the thermostat while you're looking at the app, it can cause a sync conflict that appears like a reset. Pick one place to manage the schedule.

Question 2

i replaced the batteries but the thermostat still says 'battery low' and won't let me change settings.

Accepted Answer

DIAGNOSIS The RTH9585WF uses two AAA batteries as a backup, but if it's constantly running on them (or thinks it is), it locks you out to preserve power. The main issue is that the system isn't getting proper 24V power from your C-wire, so it's draining the batteries trying to run the display and Wi-Fi. FIX This is a power problem, not a battery problem. Pull the thermostat off the wall and remove the batteries. Check the wire in the 'C' terminal on the wall plate. Is it there? Is it snug? Now, with the display off and batteries out, go check your furnace. Ensure the panel door is shut completely (tripping the safety switch) and that the corresponding 'C' wire is secure at the furnace control board. After verifying, reinstall the thermostat display. It should boot using C-wire power. Then, and only then, put fresh AAA batteries in. IF THAT DIDN'T WORK Use a multimeter to check for voltage between the 'R' and 'C' terminals on the wall plate (with wires attached). You should see a steady 24-28 volts AC. If you see 0V or a very low reading, the problem is at your HVAC system—a blown fuse on the control board is a likely suspect. HEADS UP The thermostat will always show a 'battery' icon in the status bar, even when running on C-wire power—that's normal. The 'battery low' warning is different. Also, using rechargeable NiMH batteries in this thermostat is not recommended; they have a lower nominal voltage and can trigger low battery warnings prematurely.

Question 3

the touch screen on my honeywell is getting less responsive, sometimes i have to press an icon like 5 times.

Accepted Answer

DIAGNOSIS The screen likely has a buildup of skin oils, dust, and static, or the calibration is slightly off. It's not a hardware failure yet, just needs cleaning and a reset. FIX First, power it down. Pull the display off the wall plate. This cuts all power. Take a soft, microfiber cloth (the kind for glasses or screens) and lightly dampen a corner with just water—no cleaners, Windex, or alcohol. Gently wipe the entire glass touch surface. Dry it thoroughly with another clean part of the cloth. Wait a minute, then snap it back onto the wall plate. The reboot alone can clear up temporary glitches. IF THAT DIDN'T WORK There's a hidden touch screen calibration mode. With the display on the wall, press and hold the center of the screen (between the menu icons) for about 10 seconds until you see a service menu. Use the 'Screen Cal' option to re-calibrate. Follow the prompts, which will ask you to tap specific targets on the screen. This resets its touch sensitivity map. HEADS UP Never use abrasive cloths or chemical cleaners directly on the screen. They can damage the anti-glare coating and make the problem worse. Also, if the screen is only unresponsive in one specific spot, that could indicate a failing digitizer, which would require a warranty replacement.

Question 4

how do i get this thing off the wall plate? i'm afraid i'm going to break it pulling it.

Accepted Answer

DIAGNOSIS It's on there snugly by design. There's a specific release mechanism you need to use; pulling straight out like an old thermostat will feel like you're breaking it. FIX Put your fingers on the sides of the thermostat display. Don't pull yet. Look at the very top of the display, where it meets the wall plate. You'll feel a slight lip. Gently but firmly pull the *top* of the display outward, pivoting it away from the wall plate. The top will release first. Once the top is out about an inch, you can then pull the bottom out. It's a top-release, swing-out design. There are no tabs or buttons to press, just a careful pivot from the top. IF THAT DIDN'T WORK If it's absolutely stuck, check if something (like dried paint, or the edge of the wall plate) is physically catching on the display's housing. Use a thin plastic card (like a credit card) to gently slide between the display and the wall plate at the top to break any seal or obstruction, then try the pivot motion again. HEADS UP The wires are connected to the wall plate, not the display you're removing. Once the display is off, the wires are still live with 24V AC from your furnace. Be careful not to let the bare wire ends touch each other or the metal wall plate, as it can blow a fuse on your furnace control board.

Question 5

i'm getting an 'equipment running too long' alert on the screen. what does that mean?

Accepted Answer

DIAGNOSIS It's a safety warning, not necessarily an error. The thermostat has been calling for heat or cool for a set number of hours straight (usually 12+ for heat, 6+ for cool) and is alerting you that something might be wrong, like a stuck relay or a system struggling to reach the setpoint. FIX First, check if your house is actually getting to the temperature you set. If it's freezing outside and your heat pump is running 12 hours to maintain 68°, that might be normal. You can just acknowledge and clear the alert by pressing the 'Done' button on the screen. If the temperature is way off, go to the thermostat and turn the system mode from 'Heat' or 'Cool' to 'Off'. Listen. If the furnace or outdoor unit keeps running, you have a stuck relay in your HVAC equipment itself, not the thermostat, and need an HVAC tech. IF THAT DIDN'T WORK The alert thresholds are programmable. If you get these alerts during normal operation (like in extreme weather), you can increase the limit. Go to Menu > Preferences > Alerts > Equipment Running Too Long, and you can adjust the heat and cool runtime limits to something higher. HEADS UP Don't just ignore this if your house isn't warming up or cooling down. A system running non-stop without reaching the setpoint can be a sign of low refrigerant, a failing component, or a massive air leak, which wastes money and can cause damage.

Question 6

the app says my thermostat is offline but the screen on the wall is working fine and shows it's connected.

Accepted Answer

DIAGNOSIS The thermostat has a local connection to your HVAC, but its communication link back to Honeywell's servers (and thus your app) is broken. This is almost always a problem with your home's internet connection or the thermostat's specific network path. FIX Don't touch the thermostat first. Reboot your home internet. Unplug your modem and router, wait 30 seconds, plug the modem back in, wait for it to fully boot, then plug the router back in. Give it a few minutes, then check the app. This clears router glitches that can drop specific device connections. Also, check if your internet service is actually up during these outages. IF THAT DIDN'T WORK The thermostat's own network module might need a kick. On the device, go to Menu > Wi-Fi > Network Status. If it shows connected, choose 'Clear Network' anyway, then go through the setup process to rejoin your Wi-Fi. This forces a fresh handshake with your router. HEADS UP The Total Connect Comfort app/servers have occasional outages, but they're rare. Before you spend an hour troubleshooting your gear, check Honeywell's service status page online or a site like Downdetector to see if it's on their end.

Question 7

why does my thermostat keep disconnecting from wifi? i have to keep re-adding it in the app.

Accepted Answer

DIAGNOSIS Yeah, this one's common. It's usually a weak or unstable Wi-Fi signal at the thermostat's location, or a router setting that the thermostat doesn't play nice with. FIX Start with the simple stuff. On the thermostat, go to Menu > Wi-Fi > Network Status. It'll show the signal strength. If it's one or two bars, that's your problem. You can try moving your router, using a Wi-Fi extender, or if possible, connect your thermostat to your router's 2.4 GHz network (not the 5 GHz one). The RTH9585WF only works on 2.4 GHz. Also, in your router settings, make sure you don't have 'AP Isolation' or 'Client Isolation' turned on, as that blocks device-to-device communication the app needs. IF THAT DIDN'T WORK The thermostat's internal network connection can get hung up. Do a full network reset on the device. From the thermostat, go to Menu > Wi-Fi > Clear Network. Then set it up again from scratch. This clears any corrupted connection data. HEADS UP If your router automatically swaps between 2.4GHz and 5GHz with the same network name (SSID), it can confuse the thermostat. Create a separate, dedicated 2.4GHz network with a different name (like 'HomeWiFi_2G') and connect the thermostat to that. It's more stable.

Question 8

my honeywell smart thermostat screen is completely blank, no lights, nothing. it's just dead.

Accepted Answer

DIAGNOSIS The thermostat isn't getting any power. On this model, the most common cause is the C-wire (common wire) not being properly connected or providing power at the wall plate. FIX First, pull the thermostat display straight off its wall plate. Check the bundle of colored wires. You need to see a wire connected to the terminal labeled 'C'. If there isn't one, your original HVAC setup might not have included it. If there IS a wire in the 'C' terminal, ensure it's snapped in securely. Go to your furnace/air handler and open the panel. Find where the thermostat wires connect (usually a similar terminal block). Verify the corresponding wire is firmly attached to the 'C' terminal there too. A loose wire at the furnace is a classic culprit. IF THAT DIDN'T WORK It's possible the furnace door safety switch isn't fully engaged, cutting power to the thermostat circuit. Make sure the furnace/air handler access panel is clicked all the way shut. Also, check your home's circuit breaker for the furnace/HVAC system and reset it if needed. HEADS UP If your old thermostat worked without a C-wire, it was probably stealing just enough 'phantom' power. The RTH9585WF needs a dedicated C-wire for consistent power. If you don't have one, you'll likely need to run a new wire or use an add-a-wire adapter kit, which is a whole other project.

Honeywell Home RTH9585WF WiFi Smart Thermostat

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