We’ve put together answers to the questions we get asked most about heat battery boilers, the ZEB, and more. If you don’t spot what you’re looking for, just drop us an email at customer.service@tepeo.com – we’re always happy to help.
The ZEB heat battery boiler uses electricity to store heat, which can then be used to provide heating and hot water for your home. It operates differently from a traditional boiler, which usually burns fossil fuels. The ZEB “charges” by drawing electricity—mostly during off-peak hours when energy is typically cheaper and has a lower carbon footprint. This energy is stored as heat within the unit and is available for use whenever needed.
The ZEB features smart controls. It adjusts how much heat it stores based on your heating patterns, local weather, and your energy tariff. This helps manage energy use efficiently and supports lower running costs.
How long one full charge lasts varies based on factors like the size of your property, how much heating you use, and the weather conditions. Guidance and support are available to help you use the ZEB effectively and get the most benefit from the system
Want a clear, visual explanation? Watch our video here:
The ZEB’s core is built from a proprietary blend of high-density, inert materials that are both non-toxic and designed to keep environmental impact low. You can rely on it to be safe for your home and the planet.
The ZEB stores up to 40kWh of usable thermal energy—enough to keep many homes warm and comfortable, even on chilly days.
The ZEB heat battery boiler can provide up to 15kW of heating power at its maximum output, giving peace of mind during colder spells or higher heating demands.
Just like a traditional gas or oil boiler, the ZEB can deliver hot water between 35°C and 80°C (in a suitably sized home). Most boilers don’t go higher than this, so you’ll still enjoy all the warmth you’re used to. See full compatibility details here.
When installed in a heated part of your home, the ZEB heat battery boiler is classed as 100% efficient at turning electricity into heat (for EPC purposes). If installed in an unheated space, like a garage, some warmth may escape into that area, slightly reducing efficiency and heat capacity.
For the best efficiency—especially in summer—we recommend using a hot water immersion heater with a timer for your hot water needs.
From empty, the ZEB heat battery boiler charges in about 4–5 hours but can start delivering heat just half an hour after starting from cold.
The ZEB is 98cm tall, 60cm wide, and 66cm deep. For safe installation, allow 7.5cm clearance above and 5cm on all other sides (sometimes less if your tepeoPRO installer advises).
The ZEB heat battery boiler weighs 375kg. Your installer will ensure delivery and installation are handled safely and properly.
We’ve designed the ZEB’s core for durability, so it’s unlikely to degrade over time—and could even outlast your home! Like all boilers, the ZEB does need proper maintenance, so we offer an annual ZEB Health Check and the tepeo Care Plan for complete peace of mind. Learn more here.
We recommend an annual ZEB Health Check. Our experts will check everything from system water quality and filters to electrical safety—plus, all necessary parts are included at no extra cost. You’ll get a reminder automatically each year after installation.
We currently deliver across much of the UK. Please check our delivery area mapfor up-to-date coverage. Ireland: coming soon! Register your interest here.
No need—your ZEB heat battery boiler is registered automatically during installation, and your 10-year guarantee is activated as soon as it’s set up. Terms and conditions apply.
If you have any concerns about the ZEB or tepeo App’s security, please contact our customer service team via the Contact Us page.
tepeo will provide security updates to your ZEB heat battery boiler for at least 5 years from purchase, meeting Product Security and Telecommunications Infrastructure (PSTI) regulations.
While both the ZEB and storage heaters use electricity to store energy, the ZEB heat battery boiler is much smarter. It predicts your heating needs, optimises charging for tariff and weather, and stores energy at the cheapest, greenest times—delivering reliable heat on demand, just like your old boiler.
The ZEB heat battery boiler doesn’t use fossil fuels, so you get all the warmth of a standard boiler but with cleaner, low-carbon electricity—supporting the UK’s move to Net Zero.
Unlike regular electric boilers, which use electricity whenever you need heat (often at expensive peak times), the ZEB heat battery boiler stores electricity as heat during off-peak, greener periods. This means lower running costs and less environmental impact.
Both heat battery boilers (like the ZEB) and heat pumps can lower your carbon footprint, but they suit different needs. A ZEB heat battery boiler is ideal if you want a simple, low-carbon replacement for your current boiler, as it works with existing radiators and needs minimal installation. Heat pumps are highly efficient but often require outdoor space, radiator upgrades, and extra insulation.
If you prefer a quick, low-disruption switch to low-carbon heating, a ZEB heat battery boiler could be the right choice. If your home can accommodate the installation requirements, a heat pump is also a strong option. Not sure? Our team can help you decide what works best for your home.
Absolutely! The ZEB heat battery boiler can automatically optimise its charging for Octopus Agile, taking full advantage of price changes every half hour.
The Boiler Upgrade Scheme grant for the ZEB heat battery boiler is coming soon—applications are expected to open in winter 2026. Once available, you’ll be able to apply for the grant to help reduce the upfront cost of switching to a low-carbon heating solution. We’ll share full details and the application process as soon as the scheme goes live, so check back for the latest updates or join our mailing list to stay informed.
The tepeo Early Grant Match is an exclusive offer to help customers get ahead of government support. We’re offering £2,500 off the purchase of a new ZEB heat battery boiler to match the value of the upcoming government grant. This initiative allows you to enjoy all the benefits of low-carbon heating right now, without waiting for the grant to launch. We’re doing this to help more households start saving on energy bills and cut carbon emissions as soon as possible.
Your energy spend depends on how you use your heating and which tariff you choose. Use our cost & carbon calculator. to see how much you could save with the ZEB heat battery boiler.
Installation costs vary based on your home and system, but most jobs are simple and take just 1–2 days. There’s usually no need to swap your radiators. For a tailored quote, we’ll connect you with a local tepeoPRO.
We recommend a “time-of-use” tariff with at least one off-peak period (like those from Octopus, OVO, EDF, and others), or a fully dynamic tariff (such as Octopus Agile) to maximise cost and carbon savings. Explore more tariff tips and advice here.
The ZEB heat battery boiler must be placed indoors in a weatherproof, insulated environment (such as a basement or garage).
Yes, the ZEB needs an internet connection to function and optimise charging. You can connect it via Wi-Fi or Ethernet, and it’s resilient to short outages.
You can use an Ethernet cable for a wired internet connection if Wi-Fi coverage isn’t available.
No—the ZEB heat battery boiler delivers heating and hot water just like a traditional boiler.
All ZEB installations must be carried out and commissioned by tepeo or a certified installer registered with us. This ensures your system meets all safety, legal, and manufacturer requirements. Installers interested in registering can find details on our website.
Usually, no. The ZEB is compatible with most existing central heating systems. You’ll need a hot water tank if you don’t have one already. We’ll check your home’s suitability during a survey.
You’ll need:
Power from the consumer unit (50A breaker, RCD protection, 10mm² cable)
The ZEB is compatible with most homes that have a ‘wet’ central heating system (pipes and radiators), up to 16,000kWh annual energy use and less than 6kW heat loss.
You’ll likely need a smart meter and a special tariff to access lower-cost electricity, but the ZEB heat battery boiler can still minimise your carbon footprint without one.
Yes, as long as your home’s electrical supply is sufficient. For example, a typical EV charger and the ZEB together will draw less than a typical 100A household limit—but usage of other appliances must also be considered.
Running two ZEB heat battery boilers is possible as long as your home’s supply supports their combined draw. We aim to support parallel running soon.
As with other boilers, without power your heating system won’t work, but the ZEB heat battery boiler will retain stored heat for several days, losing it gradually.
The ZEB provides up to 15kW of heat. During periods of high demand, stored heat may be used faster than it can recharge, but the ZEB can charge and discharge at the same time (with enough charge remaining).
This feature is under development.
Smart Charging enables the ZEB to charge at the cheapest and greenest times, based on your tariff, local weather, and your home’s heating needs.
Yes! The tepeo App lets you manage your ZEB heat battery boiler from anywhere, monitor energy and carbon use, and is available on iOS and Android.
Switching to a ZEB heat battery boiler from a gas boiler can save up to 2 tonnes of CO₂ per year for a typical UK home.
