Question 1

i replaced batteries in my old thermostat but nest e says no power to rh wire even though my heat works

Accepted Answer

DIAGNOSIS This is a classic misunderstanding of system types. Your old thermostat was battery-powered and only needed tiny signal wires (R and W). The Nest E needs constant power, which usually comes from the 'C' (common) wire. Your system is sending power on 'Rh' for heating, but without a 'C' wire, the Nest is struggling to get enough juice to run its brain, causing the error. FIX The proper solution is to install a 'C' wire. Look at the bundle of wires coming from your wall. If there's an unused wire (often blue or black), you're in luck. 1) Turn off power to your furnace. 2) Connect that unused wire to the 'C' terminal on the Nest base. 3) At your furnace control board, find the 'C' terminal (often labeled 'COM' or '24VAC COM'), and connect the other end of that same wire there. This gives the Nest a complete 24V circuit to sip from. IF THAT DIDN'T WORK If you don't have an extra wire, you have a couple of workarounds. You can install a Nest Power Connector at your furnace, which is a little module that provides the 'C' wire function without running new wire. Alternatively, you can try using the 'G' (fan) wire as a temporary 'C' wire, but this will disable your ability to run the fan independently from the app. HEADS UP Running a Nest without a 'C' wire using its "power stealing" feature works for many, but not all, systems. In some cases, especially with heat pumps or systems with an electronic air cleaner, it can cause the clicking issue, Wi-Fi drops, or even cause your system to short cycle. A 'C' wire is always the recommended, stable setup.

Question 2

the nest e screen stays dark unless i wave my hand right in front of it, is the sensor broken?

Accepted Answer

DIAGNOSIS The proximity sensor (the little black dot near the top) that wakes the screen is either dirty, blocked, or its sensitivity setting has been changed. It's not necessarily broken. FIX First, give the entire front face, especially the top bezel where the sensor is, a good cleaning as described in the cleaning question. A layer of dust or grime can diffuse the sensor's beam. If that doesn't help, check the settings. 1) Press the ring to bring up the Quick View menu. 2) Go to Settings > Display. 3) Look for "Farsight" or "Screen Brightness" settings. Farsight, if you have it on, keeps the screen brighter longer. More importantly, make sure "Auto-Brightness" is on so it adjusts to your room's light. IF THAT DIDN'T WORK The sensor itself might be faulty. You can test this in a dark room. The screen should not wake with a wave if it's truly dark—it uses a combination of proximity and ambient light. If it doesn't wake even in a well-lit room after a cleaning and settings check, it may be a hardware issue. HEADS UP The Nest E is designed to have a fairly dim, sleepy display to blend into your wall and save power. It's not as instantly bright as a phone screen. Also, if the thermostat's internal battery is low (check in Settings > Technical Info > Power), it will make the screen extra conservative about turning on to conserve energy.

Question 3

nest e installed but it says my system is only single stage when i know my heat pump has auxiliary heat

Accepted Answer

DIAGNOSIS The Nest E didn't correctly detect your dual-fuel or heat pump with aux heat system during its initial wiring scan. It probably has your auxiliary heat wires (often labeled W2 or AUX) plugged in, but it's configured in the settings as a conventional gas furnace system. FIX You need to manually change the equipment setup. 1) On the thermostat, go to Settings > Equipment. 2) Go through the setup prompts again. When it asks for your fuel type, select "Electric" if you have a heat pump. 3) It will then ask what wires are connected. Make sure you tell it you have both "O/B" (for the heat pump reversing valve) and "W2/AUX" (for your backup electric heat strips). This is the critical step it likely missed. 4) Complete the setup. It should now correctly stage your heat pump first, then use aux heat only when there's a big temperature gap. IF THAT DIDN'T WORK Double-check the physical wiring at your air handler/furnace. The wire connected to 'W2' or 'AUX' at the Nest base must go to the terminal for the auxiliary heat strips on your HVAC control board, not to a generic 'W' terminal for a gas furnace. HEADS UP If this is set wrong, your system can run very inefficiently. The worst-case scenario is it could run your expensive electric aux heat strips at the same time as your heat pump, which is wasteful and can overload some systems. Getting this configuration right is key for both comfort and your power bill.

Question 4

my nest e keeps losing wifi connection every day or two, i have to reboot it to reconnect

Accepted Answer

DIAGNOSIS This is usually a weak or unstable Wi-Fi signal at the thermostat's location, or the Nest's internal software getting hung up. The Nest E has a less powerful radio than the higher-end models, so it's more sensitive to distance and interference. FIX Start by checking the signal strength. 1) On the thermostat, go to Settings > Technical Info > Network. Look at the signal strength. Anything below "Good" is problematic. 2) If it's low, try changing your router's Wi-Fi channel to one less congested (like 1, 6, or 11 on 2.4 GHz). The Nest E only uses 2.4 GHz Wi-Fi. 3) The most reliable fix is to improve the signal. You might need a Wi-Fi extender placed between your router and the thermostat, but make sure it's a quality one that creates a stable network. IF THAT DIDN'T WORK If the signal is strong but it still drops, it could be a software bug. Perform a full restart: go to Settings > Reset > Restart (not a full factory reset). This clears its temporary memory. If problems persist, you may need to remove the device from your Google Home app and set it up again as new, which reinstalls the software. HEADS UP Thick walls, metal ductwork, and large appliances (like refrigerators) between your router and thermostat can kill a 2.4 GHz signal. Also, some older modem/router combos from ISPs are notoriously bad at maintaining stable connections with smart devices.

Question 5

how do i clean the nest e screen? it's got fingerprints and smudges and my shirt just makes it worse

Accepted Answer

DIAGNOSIS The frosted plastic display on the Nest E is a smudge magnet. Using dry cloths, especially microfiber, can create static that actually attracts more dust, and oils from your skin or clothes just smear around. FIX You need to break the oil down. 1) First, pop the display unit off its base by pulling it straight towards you. This lets you clean it safely away from the electrical connections. 2) Use a very slightly damp, soft, lint-free cloth (like a glasses cleaning cloth). Plain water is best. 3) Gently wipe the screen in a circular motion. 4) Immediately dry it thoroughly with a different dry, soft part of the cloth before reattaching it. Don't spray any liquid directly onto the thermostat. IF THAT DIDN'T WORK For stubborn smudges, you can dampen the cloth with a tiny, tiny drop of mild dish soap diluted in water. Wipe gently and follow with a water-dampened cloth to remove any soap residue, then dry completely. Isopropyl alcohol is riskier as it can damage the frosted coating over time. HEADS UP Never use window cleaners, abrasive cloths, or paper towels. The plastic scratches more easily than glass. Also, make sure the unit is completely dry before snapping it back onto the base—you don't want moisture seeping into the connectors.

Question 6

nest e says delayed for 2+ hours when i try to turn on the heat, but the furnace never starts

Accepted Answer

DIAGNOSIS The Nest is in a safety lockout mode. It tried to turn on your heating system, didn't detect that it actually fired up, and is now waiting a long cooldown period before trying again to prevent damage. This is almost always a problem with your furnace itself, not the thermostat. FIX Go directly to your furnace. 1) Check if the furnace's own control board has a blinking LED light. Count the blinks. 2) Consult the sticker inside the furnace door or for the fault code that blink pattern represents. Common culprits are a dirty flame sensor or a faulty pressure switch. 3) To reset the furnace and clear the Nest's "Delayed" message, you need to cut power to the furnace completely at its switch or breaker for about 30 seconds, then restore it. IF THAT DIDN'T WORK If the furnace seems fine and starts right up if you bypass the Nest (by touching the R and W thermostat wires together briefly), then the issue is the Nest's 'W1' heating signal. The wire might be loose at the baseplate or at the furnace. Check both ends. HEADS UP When you see "Delayed," the thermostat is basically telling you it's done its job and is now waiting on the equipment. Forcing it to try again by constantly adjusting the temperature won't help and can confuse the system. Address the furnace fault first.

Question 7

why is my nest e making a faint clicking sound every few minutes when the heat is off?

Accepted Answer

DIAGNOSIS That's the internal relay inside the thermostat clicking on and off. It's trying to send a signal to your HVAC equipment, but it's not getting the expected response, so it cycles. This often points to a wiring issue or a mismatch between what the Nest thinks is connected and what's actually connected. FIX The first thing to check is your wiring setup in the Nest app. 1) On the thermostat, go to Settings > Technical Info > Power. 2) Look at the readings for Voc and Vin. If Vin is very low (like below 3.7V) or jumping around wildly, it indicates a power stealing issue. 3) The best permanent fix is to ensure you have a proper 'C' (common) wire connected to provide constant power. If your thermostat cable has an unused wire, you'll need to connect it at both the Nest base and at your furnace control board. IF THAT DIDN'T WORK The clicking can also happen if a wire is loose or if there's a slight short. With the HVAC system power OFF, pop the display off and check each wire is securely seated under its connector on the baseplate. A wire strand touching another terminal can cause this. HEADS UP Don't ignore this. That constant relay clicking and power searching can, over a long period, drain the Nest's internal battery and lead to it shutting down unexpectedly or losing Wi-Fi connection.

Question 8

my nest thermostat e just went blank and won't turn on, no lights or anything, what do i do?

Accepted Answer

DIAGNOSIS Your thermostat has lost all power. This isn't a software crash; it's a power issue at the wall. The most common cause for a sudden, complete blackout is the HVAC system's fuse blowing or a tripped safety switch. FIX First, check your home's main electrical panel for any tripped breakers related to your furnace or air handler and reset them. If that's fine, you need to check the furnace itself. 1) Turn off the power to your furnace/air handler at its own switch or at the breaker. 2) Open the furnace door. There's usually a little 3-amp or 5-amp car-style fuse on the control board inside. 3) Pull it out and check if the thin wire inside is broken or the glass is cloudy. 4) Replace it with an identical fuse from an auto parts store. Turn the power back on. Your Nest should wake right up. IF THAT DIDN'T WORK The issue could be with the Nest's baseplate wiring. Turn the HVAC power back off, pop the Nest display off its base, and check that all the tiny wire connectors on the base are pushed down fully. Sometimes one gets loose and breaks the 'C' (common) wire connection, starving it of power. HEADS UP If you don't have a 'C' wire connected at all, the Nest E tries to steal a tiny bit of power from your system when it's off. In some systems, this can eventually drain the internal battery and cause a black screen, especially if your system doesn't run for long periods.

Nest Thermostat E

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