There are plenty of things you can do with an old computer once you no longer use it as your primary work or entertainment machine. You can turn it into a NAS, or even make a digital photo frame out of an old laptop. Another option you have in this modern era is turning your PC into a smart home hub, allowing you to control your devices in a centralized interface without depending on cloud services.

This is made possible through the magic of Home Assistant, and if you want to install it on your PC, we're here to help with that. Setting up Home Assistant on an old PC does take some work, but it's a great way to repurpose hardware you're not using anymore, and it can save you a good bit of money.

What you'll need

Before we get started, here's some of the equipment you're going to need:

• An unused PC with an Ethernet connection and UEFI support - This will be your Home Assistant server. This is not needed if you use a virtual machine instead.
• A formatted flash drive with at least 8GB of capacity - This will be used to install Home Assistant on your PC.
• Virtualization software - If you choose to create a VM for Home Assistant, you'll need software like VirtualBox or VMware Workstation Player.
• A second computer or phone - This will connect to your Home Assistant server to perform the configuration. If you have a VM, you can simply use the host PC instead.
• A VPN (optional) - If you want to access your smart home remotely, you'll need a VPN to be able to link to your Home Assistant server from outside your local network.

Preparing your PC for Home Assistant

To be clear, you can set up Home Assistant in a variety of ways. The team behind the project sells dedicated devices for setting it up, and you can also use a Raspberry Pi, or even a virtual machine on whatever OS you're currently using. There are plenty of options. However, we're going to focus on installing the Home Assistant OS on your PC as the primary operating system.

For this, you're going to need a PC that supports UEFI boot, which is a very widespread feature on modern PCs. If your PC is made in the past 10 years, it's almost guaranteed to support it. Your PC also needs to have an Ethernet port.

Disabling device encryption

We're assuming you're running Windows 11, and in this case, the first thing you're going to need to do is make sure device encryption or BitLocker drive encryption are turned off. To do this:

1. Open the Settings app and choose Privacy & security from the menu on the left.
2. Select Device encryption.
3. Make sure the feature is set to Off. If your turn it off, wait for it to finish decrypting before continuing. On machines with Windows 11 Pro, you may need to open BitLocker drive encryption to turn off encryption for all your drives.

You can opt not to disable device encryption, but you will need to enter your BitLocker recovery key later. You can find that in your Microsoft account management page.

Disable Secure Boot

In order to boot the Home Assistant OS, you're also going to need to disable Secure Boot, which is why you have to decrypt your drive in the first place. To disable Secure Boot, you'll have to go into your computer's BIOS. Here are the steps:

1. In Windows, open the Settings app.
2. Go to System and then choose Recovery.
3. Click the Restart now button next to Advanced startup.
4. After your computer restarts, you'll be in a blue screen. Selectr Troubleshoot and then Advanced options.
5. Click UEFI Firmware Settings.
6. Your computer will restart again, this time into your BIOS/UEFI settings. Here, every PC is going to look different, but you should look for an option called Secure Boot. It's often under a tab called Boot or Security.
7. While you're in the BIOS, check if there's an option to enable UEFI boot. Some PCs that support UEFI may have this option disabled, but you'll want to make sure it's enabled. If you don't see it, your PC may already use it by default.
8. Save your changes and restart your computer.

Installing Home Assistant OS

Creating an Ubuntu flash drive

Once your PC is ready, you can start the process to install Home Assistant OS on it. The recommended method for this is using a live Ubuntu flash drive to download and install the image. That means you need a USB flash drive with at least 8GB of capacity with no data on it (or data you don't mind losing). Here's how it goes:

1. Download the latest version of Ubuntu from the official website.
2. Download (and install) Rufus from its official website.
3. Insert the flash drive into your PC.
4. Open Rufus and, under Boot selection, make sure it reads Disk or ISO image and then click SELECT.
5. Select the Ubuntu file you downloaded in step 1.
6. Click START and wait for the process to complete.

   This will delete all data on your flash drive.

With your USB flash drive ready, you you'll now have to boot from it.

Using Ubuntu to install Home Assistant

Now, you'll want to plug in your flash drive into the PC where you're going to be installing Home Assistant. To boot from your drive, follow these steps:

1. Boot into Windows normally and open the Settings app.
2. Go to System and choose Recovery.
3. Click Restart now next to Advanced startup.
4. Once you get to the blue screen, click Use a device.
5. Choose the USB drive you plugged in.
6. Once your computer boots from USB, you'll be given some options for booting Ubuntu. Choose Try or install Ubuntu.
7. Follow the setup process until you get to the desktop. Make sure to connect to the internet.
8. From here, launch the browser (Firefox). To download the Home Assistant image, visit this article and click here to download it.
9. Open the Applications menu (in the bottom left corner) and search for Disks (you can start typing after opening the menu).
10. In the Disks tool, select the main drive on your PC (it should be the first one).
11. Click the three-dot button and choose Restore Disk Image.
12. Select the image you downloaded and click Start restoring....
13. Click Restore again to confirm.
14. Once the process finished, use the power menu in the top right to turn off the computer. Once it's off, remove the USB drive.

    You may see another Ubuntu screen asking you to remove the flash drive instead of the computer turning off completely. If this is the case, remove the drive when requested.

15. Boot up your computer again and it will boot into Home Assistant OS. This is where you need the Ethernet connection to allow Home Assistant to download additional packages.
16. Eventually, you'll get to the Home Assistant banner screen. This concludes the installation process.

Alternative: Installing Home Assistant on a virtual machine

If you'd rather use a PC that's running Windows and have Home Assistant run as a virtual machine instead, you also have that option. Using your virtual machine software of choice (such as VirtualBox, VMWare, or Hyper-V), you'll want to create a VM for a Linux-based machine with an internet connection, at least 2GB of RAM, 32GB of storage, and two virtual CPUs.

Rather than using an ISO, the Home Assistant team recommends downloading a full system disk image. You can download them below depending on the virtualization software you're using:

• Home Assistant image for VirtualBox (VDI)
• Home Assistant image for VMWare Workstation Player (VMDK)
• Home Assistant image for Hyper-V (VHDX)

If you're comfortable, you can even set up Home Assistant OS using Windows Subsystem for Linux.

Setting up Home Assistant

Add your devices

Setting up Home Assistant is relatively easy from here. Of course, it will depend on the smart home devices you have, and some may require more steps to set up than others. We can't dive into all the specifics for each device here. However, here's what the general set up process looks like:

1. On a different computer, go to homeassistant.local:8123 in your browser. If it doesn't work, check the URL shown on the screen of your Home Assistant PC.
2. You'll be prompted to create your smart home. Click Create my smart home to get started.
3. Enter a name for your account and choose a password.
4. Choose a location for your home. This allows Home Assistant to deliver weather information.
5. If you want to share data with the Home Assistant developers, you can enable the toggles. However, they're off by default.
6. Home Assistant will detect any devices in your home. Click Finish and the devices detected will be added to your dashboard.

With the dashboard set up, you can now start configuring and controlling your devices. Some devices may not automatically be configured, but you can set them up in the Settings tab. This is also where you can manually add more integrations, automations, install add-ons, and more.

How to control your home from anywhere

Use a VPN to access your home

Since Home Assistant runs on your local network, by default, you can't control your home if you're not connected to your home network. However, you can work around this. The official recomnmended method is paying for Home Assistant Cloud, a subscription service that makes the process a bit easier if you're willing to pay.

If you want to do this for free, though, you can use a VPN to make it possible. One of the common recommendations is using Tailscale.

Setting up Tailscale on your Home Assistant PC

First, you'll have to set up Tailscale on the Home Assistant server. For this, follow these steps:

1. Open your Home Assisant configuration (homeassistant/local:8143)
2. Click Settings on the sidebar.
3. Choose Add-ons, and then click Add-on Store at the bottom of the page.
4. Search for Tailscale and select the card that appears.
5. Click Install.
6. Once installed, make sure the Start on boot, Watchdog, and Show in sidebar are all enabled. The last one is mostly for ease of access, so you can skip it if you want.
7. Click Start.
8. Once the service is running, click Open Web UI.
9. Click Reconnect if prompted, and a new tab will open for you to login. Enter the email you want to use or use one of the alternative sign-in methods.
10. After logging in, click Connect to connect your Home Assistant PC to your Tailscale account.
11. You'll see a list of your machines, which shows the IP address of the machine you just added. You'll want to write it down or remember it.

At this point, you've set Tailscale up as far as you need to. All you need to do now is install the Tailscale app on your phone or computer to access your Home Assistant server remotely. Simply install the app using the link below and sign in using the same account you used for your Home Assistant PC. Whenever you want to connect to your Home Assistant server, simply turn on the VPN profile and then open your web browser and enter the IP address of your Home Assistant server, followed by the port used by Home Assistant (8123). The address should look something likethis: XXX.XXX.XXX.XX:8123.

Make the most of your old PC

Home Assistant is one of the best ways to repurpose an old PC if you have a lot of smart devices in your home. It gives you a local, secure way to control your smart home devices, while also giving you the option to securely connect over the internet if you want remote control. There are a lot of integrations and automations available through this system, so we really recommend taking the time to learn the ins and outs to make the most of it. These steps are just to get you started.