# High CPU Spikes about Every 2 Hours & Persistent Unknown Zigbee Nodes after Network Reset **URL:** \ **Category:** Questions & Help\ **Created:** [July 27, 2026, 5:15am UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602 "2026-07-27T05:15:49Z")\ **Posts on this page:** 14\ **Page:** 1
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 27, 2026, 5:15am UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/1 "2026-07-27T05:15:49Z")
Hi everyone, I am facing a strange issue with my **Homey Pro (2026)** where the CPU regularly spikes up to 90–100% in a about **2-hour cycle**. This behavior started about 14 days ago, and I need your help finding the root cause. ### 🛠 What I Have Already Tried & Checked: - **App Performance:** I checked all installed apps in the Developer Tools. They are idling normally, using only about 1–3% CPU maximum. - **Integrations:** I do **not** use MQTT or Home Assistant. - **Other Protocols:** I have checked my Z-Wave devices; they all have full batteries and none of them are spamming the network with high Tx/Rx counts. I also have one weather station running on 433/868 MHz. - **Reboots:** I have restarted the Homey Pro multiple times, which did not resolve the issue. - **The Dashboard Setup:** I currently run the official Homey Web App (`my.homey.app`) as a permanent smart home dashboard on an **Apple iPad Pro** mounted on the wall. ### ❓ My Questions to the Community: #### 1. What could be causing these 2-hour CPU spikes? Given that my apps look fine and my Z-Wave network is quiet, what else could trigger such a precise, mechanical 2-hour load pattern? What are your suggestions or troubleshooting steps to isolate the culprit? #### 2. How do I handle these “Unknown Zigbee Nodes”? I recently did a full **Zigbee network reset**. Despite this, I have two persistent _“Unknown Nodes”_ showing **100% TX-Error** in the developer tools, but with very recent _“Last Seen”_ timestamps (e.g., 30 minutes ago). - How can I find out _which_ physical devices these actually are? (They do not show up under the main _Devices_ tab when filtering for their IEEE/MAC addresses). - Since the _Remove_ button is gone in the newer Developer Tools, how can I completely get rid of them and clear them from the Zigbee chip’s memory? #### 3. What are the normal operating ranges for CPU load and temperature? To better monitor my system without getting unnecessary headache over normal spikes: - What is considered the **healthy normal range** for a Homey Pro (2026) regarding average CPU load and core temperature? - At what point do these values become **borderline/critical** , and when is it definitively **too much**? Thanks in advance for your ideas, brainstorming, and help! ![Bildschirmfoto 2026-07-27 um 07.04.46](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/2/9/2978c4233f986aa6d1c91ce7148fda8c77767534.jpeg) ![Bildschirmfoto 2026-07-27 um 07.05.23](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/e/8/e84ee00f940a8042648d56b82979cafba5fedd7b.png) ![Bildschirmfoto 2026-07-27 um 07.05.12](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/4/c/4cd64775c1306380f2012776f5b31c822b5ae1b0.jpeg) ![Bildschirmfoto 2026-07-27 um 07.13.39](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/1/4/14a140ed337ad109254c26b64aac43f1b3d23000.png) ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 27, 2026, 8:27am UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/2 "2026-07-27T08:27:17Z")
FYI - These are the stats for my Homey Pro 2026. Average load in the top graph; temperature in the bottom graph. _Last hour_ ![IMG_2826.PNG](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/9/e/9e936aa011de2e5d4bfcb47d7890c4b21be1e524.jpeg) _Last 24 hours_ ![IMG_2828.PNG](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/9/1/917b563d6860ae2d27870240d43bf2101bcd1caa.jpeg) _Last 7 days_ ![IMG_2827.PNG](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/f/e/fea0444e2913047f07dc92949ad11be4cdc137a4.jpeg) ---
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 27, 2026, 7:10pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/3 "2026-07-27T19:10:29Z")
Do you have any ideas what I‘m doing wrong or is my Homey distroyed or inconsistent? ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 27, 2026, 7:40pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/4 "2026-07-27T19:40:54Z")
No I’m sorry, I don’t. If you cannot track it down to a specific app or something else, then you might want to reach out to Athom support via [Support | Homey](https://homey.app/support/). Regarding the unknown Zigbee devices: try powering down your Homey (pul the plug) for 15 minutes. Then restart your Homey and let it rebuild your Zigbee network. Check if the unknown devices are gone. ---
**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\ **Post date:** [July 27, 2026, 11:43pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/5 "2026-07-27T23:43:08Z")
Possibly be due to a recent Homey update to a new Debian version > [@Sudden CPU frequency drop from 1.3GHz to 0.9GHz since v13.3.0](https://community.homey.app/t/sudden-cpu-frequency-drop-from-1-3ghz-to-0-9ghz-since-v13-3-0/156562/14): > > I quickly checked with the team, and the most likely explanation is that the move to the Debian Bookworm base also changed the CPU frequency governor. On Debian Bullseye, the default governor was typically ondemand, whereas newer kernels used by Debian Bookworm generally default to schedutil. The main difference is that schedutil adjusts the CPU frequency much more dynamically based on the scheduler, while ondemand periodically samples CPU utilization and often keeps the CPU at higher frequenci… > [@Sudden CPU frequency drop from 1.3GHz to 0.9GHz since v13.3.0](https://community.homey.app/t/sudden-cpu-frequency-drop-from-1-3ghz-to-0-9ghz-since-v13-3-0/156562/26): > > I understand why it looks that way, but that’s not quite how it works. The CPU isn’t simply being “fed less power.” Modern SoCs continuously adjust both their clock speed and voltage based on the current workload. When there’s little work to do, the CPU runs at a lower frequency and voltage to save power. As soon as more performance is required, the governor increases the frequency again. It’s also important to distinguish between CPU utilization and CPU performance. Running at a lower frequen… ---
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 28, 2026, 7:41pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/6 "2026-07-28T19:41:32Z")
Thank you for the detailed explanation! However, I don’t believe that’s the actual issue here. As you can see in the screenshot above, others have significantly lower temperatures and CPU utilization on their devices. Something seems to be wrong with my Homey – what exactly could be going on? Additionally, I’m having trouble reaching support via chat. I keep getting stuck in an endless login loop (login, login, login…). Is there a way to mention support here using an `@` or something similar so someone can take a look into this? ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 28, 2026, 7:48pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/7 "2026-07-28T19:48:41Z")
> [@Dominic\_Gutleben](#): > > I’m having trouble reaching support via chat. You can contact them via: > **[Support | Homey](https://homey.app/en-us/support/)** After logging in select your Homey and then choose Other: ![IMG_2837](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/1/1/1188373569efffd3c410e819dfa3724cb82bfa48.jpeg) And then scroll down where you’ll find the contact link: ![IMG_2838](https://us1.discourse-cdn.com/flex025/uploads/athom/original/3X/7/3/737f938c8b3e4c18a79e0d952d8138cf4317c5e9.jpeg) ---
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 28, 2026, 8:03pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/8 "2026-07-28T20:03:33Z")
Thanks, but it only shows me the option for the knowledge base there. ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 28, 2026, 8:08pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/9 "2026-07-28T20:08:58Z")
Did you sign in? If so your Homey Pro 2026 should be listed there as well as the indicated options. ---
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 29, 2026, 5:46pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/10 "2026-07-29T17:46:32Z")
Yes I’m signed in but have only the option for knowledge base. ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 29, 2026, 6:34pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/11 "2026-07-29T18:34:28Z")
That is really strange… Just to double check: after loggin in you select your account and then your Homey Pro 2026-device under My Homeys (not another Homey type like SHS)? If you cannot get the support link to appear, then - instead of selecting your Homey - select the option ‘My Homey isn’t listed’ and fill in the support request form. ---
**Author:** ![Dominic\_Gutleben](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/dominic_gutleben/32/121387_2.png) [@Dominic\_Gutleben](https://community.homey.app/u/Dominic_Gutleben)\ **Post date:** [July 30, 2026, 6:09pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/12 "2026-07-30T18:09:14Z")
Exactly. I log in, choose my account, and then I can’t select a Homey at all. I’m caught in an endless loop and can’t reach support. One additional question: Is there no easy way to make local backups? Like downloading the cloud backup, for example? Do you guys always install all updates immediately, or do you keep your system running on a stable version for quite a while? Also, with the online backups, is it possible to go back further than the last 7 days? PS: Since yesterday’s update, the CPU usage seems to be back to a max of 40-50% - so I guess it was an update? ---
**Author:** ![SunBeech](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/sunbeech/32/111391_2.png) [@SunBeech](https://community.homey.app/u/SunBeech)\ **Post date:** [July 30, 2026, 7:01pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/13 "2026-07-30T19:01:24Z")
> [@Dominic\_Gutleben](#): > > Exactly. I log in, choose my account, and then I can’t select a Homey at all. I’m caught in an endless loop and can’t reach support. Okay, that means that your Homey is not linked to the account you are signing in with. You might want to check that. For now, try the alternative route: instead of selecting your Homey, select the option ‘My Homey isn’t listed’ and fill in the support request form. > [@Dominic\_Gutleben](#): > > Is there no easy way to make local backups? Like downloading the cloud backup, for example? You can also make full local backups (including the installed version of Homey OS and apps), thought the process it is less user-friendly. You have to connect your Homey to a computer. Check this knowledge article for more info: [Connect Homey Pro to a PC or Mac with USB](https://support.homey.app/hc/en-us/articles/7263435817116-Connect-Homey-Pro-to-a-PC-or-Mac-with-USB). Keep in mind that the cloud backups only include your settings, devices and flows. You cannot use it to restore to a prior Homey OS version. > [@Dominic\_Gutleben](#): > > Do you guys always install all updates immediately, or do you keep your system running on a stable version for quite a while? I usually wait several days and check for user reports on this forum and on Homey’s Slack channel. Depending on the changes I sometimes make a local back-up, so that I can restore the prior Homey OS firmware if needed. Then I update, if there are no reported issues that might affect my setup. As far as I am able to determine of course. > [@Dominic\_Gutleben](#): > > Also, with the online backups, is it possible to go back further than the last 7 days? Not that I am aware of. Note that regarding flows, you can [manually export (and import) them](https://community.homey.app/t/web-app-alt-context-menu-export-import-flows/143013) as an extra backup. ---
**Author:** ![Peter\_Kawa](https://sea1.discourse-cdn.com/flex025/user_avatar/community.homey.app/peter_kawa/32/173848_2.png) [@Peter\_Kawa](https://community.homey.app/u/Peter_Kawa)\ **Post date:** [July 30, 2026, 8:15pm UTC](https://community.homey.app/t/high-cpu-spikes-about-every-2-hours-persistent-unknown-zigbee-nodes-after-network-reset/157602/14 "2026-07-30T20:15:05Z")
> [@Dominic\_Gutleben](#): > > is it possible to go back further than the last 7 days? It is possible, but only if you disable the auto-backup toggle. The backup system just keeps the last 7 backups, not related to days. When you enable it one night a week, you create 7 week backups like that. Far from practical, but it is possible this way. (I tried to control the auto-backup toggle using Homeyscript, but unfortunately we only can _get_ the toggle status, it’s not allowed to _set_ it (which is quite insane of course)). In 6 years of using Homey, I never needed a cloud backup older than a few days, just saying. → It might be a plan to temporary disable auto-backup when away for more than a week, like vacation or business trips. Usually you don’t make important changes @ Homey during.