Written by James Walker · Home Automation & Security Editor
If you’ve ever wondered how often you should update smart thermostat firmware, you’re asking a good question that most manufacturers don’t explain clearly. In my testing experience, the honest answer is that you rarely need to think about it at all — most devices handle this automatically in the background — but knowing what “often enough” looks like still matters for safety and privacy.
This guide covers how smart thermostat firmware updates actually work, how often you should realistically check on them, what can go wrong if updates are ignored for too long, and when a firmware issue points to something a professional should look at instead.
How Often Should You Update Smart Thermostat Firmware? The Basics
Firmware is the built-in software that runs a thermostat’s screen, app connection, scheduling, and security features. Manufacturers release updates to fix bugs, patch security issues, and sometimes add new features, and most modern smart thermostats are designed to download and install these updates automatically once connected to Wi-Fi.
So how often should you update smart thermostat firmware in practice? For most UK households, the real answer is “you shouldn’t need to do it manually very often” — automatic updates typically happen every few weeks to a few months, depending on the manufacturer’s release schedule. What matters more is checking occasionally that automatic updates are actually working, rather than updating on a strict calendar.
This matters slightly differently depending on your home setup. In an older UK property where the thermostat sits on a shared or congested Wi-Fi network, updates can sometimes fail silently in the background, whereas a newer home with a strong, dedicated network connection tends to receive updates more reliably.
Why Firmware Update Frequency Matters for UK Homes
Firmware updates often include security patches that address vulnerabilities discovered after the device was released. A thermostat running old firmware for many months can be left exposed to issues the manufacturer has already fixed for everyone else, which is one reason checking update status occasionally is worth the small effort.
There’s also a reliability angle specific to UK heating. Firmware updates sometimes improve how a thermostat communicates with its boiler receiver unit, fixing scheduling glitches or improving how the device handles temporary loss of Wi-Fi. Falling badly behind on updates can mean missing out on these practical fixes, though it won’t usually stop the thermostat controlling the boiler at a basic level.
How Firmware Updates Work Technically
Most smart thermostats check a manufacturer’s server periodically over Wi-Fi to see if a new firmware version is available. If one is found, the update downloads in the background and installs during a low-activity period, often overnight, without needing anything from you. This process runs over your home network and 230V mains-powered thermostat electronics; it has no connection to your boiler’s wiring centre or fused spur.
Because this all happens over Wi-Fi, the reliability of updates depends heavily on your router’s signal strength at the thermostat’s location, and whether the device has been left disconnected from Wi-Fi for a long stretch (for example, after a router replacement or a change of broadband provider).
Automatic vs Manual Firmware Checks
A beginner can usually just leave automatic updates switched on and check the thermostat’s “About” or “Software” menu every couple of months to confirm the version number has changed recently. A more experienced smart home user will also check the manufacturer’s release notes page occasionally, since not every update is pushed to every device at exactly the same time.
Automatic vs Manual Firmware Checks Compared
Here’s a simple flow for checking and installing a smart thermostat firmware update manually:
Open the manufacturer’s app or the thermostat’s on-device Settings menu.
Navigate to “About,” “Software,” or “Firmware” to see the current version and date.
Select “Check for Updates” if the option is available.
Keep the thermostat connected to Wi-Fi and powered while the update installs.
Confirm the version number has changed once the thermostat restarts.
Practical takeaway: checking twice a month is more than enough for most homes — the process itself only takes a minute or two.
Setting a Sensible Firmware Check Routine
Check for a firmware update immediately after unboxing and setting up a new thermostat.
Enable automatic updates in the app if this isn’t already the default setting.
Do a quick manual check every 1-2 months, especially after any router or broadband changes.
Check again after any long period the thermostat may have been offline (holidays, power cuts).
Review the manufacturer’s release notes if you notice odd scheduling or app behaviour.
Contact manufacturer support if a device seems stuck on very old firmware with no updates appearing.
Privacy and Data Security Considerations
Firmware updates are one of the main ways manufacturers patch security weaknesses that could otherwise be used to access a thermostat’s stored Wi-Fi details, schedules, or account data. A device left many months or years behind on updates may be running with known issues that have already been fixed on current firmware.
To reduce data exposure, keep automatic updates enabled where possible, use a strong unique password for the manufacturer’s account, and periodically check the app’s privacy settings for anything you’d rather turn off, such as optional usage-data sharing.
A quick decision path if you’re not sure how often you should update smart thermostat firmware for your specific device:
Is automatic update enabled in the app or on-device menu?
→ Yes: A quick manual check every 1-2 months is usually enough as a backup.
→ No: Turn it on if available, and check manually roughly every few weeks until you’re confident it’s working.
Practical takeaway: enabling automatic updates removes most of the guesswork about update frequency.
Common Problems and Fixes
Problem vs Likely Cause
Common Mistakes With Firmware Updates
The most frequent mistake is assuming a thermostat updates itself forever without ever checking, when in fact a weak Wi-Fi signal or a router change can quietly stop updates from installing for months. A close second is disconnecting power or Wi-Fi mid-update, which can occasionally leave a device in an unstable state until it’s power-cycled.
Mistake vs Better Choice
Safe Setup vs Risky Setup
Signs your thermostat’s firmware situation could use a second look:
The firmware version hasn’t changed in well over a year, which can mean updates have quietly stopped working.
The app keeps showing an “update failed” message, often pointing to a weak Wi-Fi signal near the device.
The device is old enough that the manufacturer no longer lists it as supported, meaning updates may have stopped entirely.
Schedules or temperature readings behave oddly after a long gap without updates, worth checking against the current firmware version.
Practical takeaway: most of these signs point to a Wi-Fi or settings issue, not a wiring fault, and are usually simple to fix.
Which Update Routine Fits Your Household?
Household/Routine Fit Table
tado° Smart Thermostat X
A wired smart thermostat with regular manufacturer firmware releases, which may help with scheduling consistency once updates are kept current.
Eve Thermo
A battery-powered radiator valve with app-based update checks that may make monitoring firmware status a little easier for renters.
Pro Tips and What Experienced Users Check
Beginners usually never look at the firmware version at all, and just assume it’s handled. Experienced smart home users go further — they check the version number every so often, glance at release notes for security-related fixes, and confirm the manufacturer is still actively supporting the model before relying on it for years.
A practical priority guide for smart thermostat firmware habits, shown as relative bars:
Keeping automatic updates enabled
Checking Wi-Fi signal strength near the device
Reading release notes for security fixes
Manually forcing an update check every month
Practical takeaway: enabling automatic updates and keeping a solid Wi-Fi signal matter more than manually forcing checks all the time.
Which firmware check approach tends to fit which UK home type:
Thicker internal walls can weaken Wi-Fi near the thermostat, so checking updates monthly is a sensible habit here.
Usually has stronger, more modern Wi-Fi coverage, so automatic updates tend to install reliably with less manual checking needed.
Broadband providers or routers may change between tenancies, so a firmware check after any such change is worth doing.
Long stretches offline can mean firmware falls behind; check status whenever you visit or before letting the property out.
When to Contact a Professional
DIY vs Hire a Professional
Reliable, independent guidance on keeping connected devices secure is available from the National Cyber Security Centre’s device security guidance, and general privacy considerations for smart home devices are covered by the Information Commissioner’s Office. Details on when electrical work needs to meet Part P can be found on GOV.UK’s building regulations approval page.
Frequently Asked Questions
How often should you update smart thermostat firmware?
Most thermostats update automatically every few weeks to a few months, so you don’t need to update manually on a set schedule. A quick check every 1-2 months is a sensible habit as a backup.
What happens if I never update my smart thermostat’s firmware?
The device may run without security patches the manufacturer has already released, and could miss out on bug fixes affecting scheduling or app connectivity.
Do firmware updates affect my boiler wiring?
No, firmware updates only affect the thermostat’s internal software over Wi-Fi. They have no connection to the boiler’s wiring centre or mains electrical circuits.
Can I stop a firmware update once it’s started?
It’s best not to. Disconnecting power or Wi-Fi mid-update can occasionally leave the thermostat in an unstable state until it’s restarted.
Why does my thermostat’s firmware version never seem to change?
This often points to a weak Wi-Fi signal at the thermostat, automatic updates being disabled, or the model no longer receiving manufacturer support.
Do firmware updates improve privacy?
They can help by patching known security issues, but no update can guarantee complete protection. Pairing updates with a strong, unique account password supports better privacy overall.
Should I call an electrician about a firmware problem?
Not usually. Firmware issues are software-related. Only involve a registered electrician if the problem genuinely turns out to involve wiring or the boiler’s wiring centre.
Working out how often you should update smart thermostat firmware really comes down to trusting automatic updates for most of the work, then doing a simple check every 1-2 months to confirm everything is still current. It’s a small habit that supports better security without needing constant attention.
For anything involving your boiler’s wiring centre, fused spur, or consumer unit, always use a registered electrician and check current UK Building Regulations (Part P) before making any permanent electrical installation.