Why Air Source Heat Pumps are Replacing Oil Boilers

If your home uses an oil boiler, you’ll be all too familiar with the realities of living with this technology: the expensive fuel, increasing maintenance costs as it ages, and having to manage oil deliveries, to name just a few. You’ll also have sacrificed space in your garden for the tank, and will be living with the risk of a messy, dangerous (and expensive!) leak.

Fortunately, for those not on the gas grid, there is now a better option to centrally heat your home. Heat Pumps are a cost-effective, energy-efficient and low-maintenance alternative to oil boilers. Boiler owners across the country are switching out their old systems for heat pumps, and grabbing a healthy £7,500 grant from the government to do so. If you’re considering joining them, this article is for you. We'll talk about the key advantages of heat pumps over oil boilers, and address some of the common concerns that homeowners looking to switch might have. Hopefully at the end of it you’ll feel better informed - and if you want more information, you can speak to one of the experts at Fornax for a free consultation at any time.

What is a heat pump, and how do they work?

Heat pumps take heat from the outside world and transfer it into your house. All they need to work is an electricity supply, and a tank for the hot water. This is in contrast to combustion boilers, which make heat by burning a fuel source, such as heating oil. 

There are two types of heat pump - air source and ground source - which take heat from the air and ground respectively, and use it to provide space heating and hot water. For nearly all homes in the UK, air-source heat pumps are more practical. They still heat homes even in outside temperatures as low as -20°C (not something you can expect to experience in the UK thankfully), and they’re much cheaper and easier to install. When we talk about heat pumps in this article - and elsewhere on the Fornax website - we’re usually talking about air source heat pumps.

Image: A modern air-source heat pump

Heat pumps connect to existing water-based central heating systems (such as radiators or underfloor heating), making them a versatile and effective replacement for oil boilers.

Superior energy efficiency & lower running costs

One of the most compelling advantages of heat pumps is their remarkable energy efficiency. Unlike traditional boilers that create heat through burning fuel, heat pumps simply transfer existing heat from the outside air into your home. This transfer process requires only a small amount of electricity to power the pump and compressor.

As a result, modern heat pumps operate at an incredible 300-400% efficiency. To put this into perspective, even the most advanced oil boilers max out at around 85% efficiency when converting the energy from burning oil into usable heat. A typical heat pump achieves the same heating output while consuming just one-fifth of the energy required by an oil boiler.

The implications for your energy bills are significant. While the savings can vary depending on fluctuating tariffs and market forces, a heat pump could reduce your heating costs by 20% or more compared to an oil boiler, based on current average prices. And the future looks even brighter, as electricity prices are widely expected to fall relative to fossil fuels in the coming years, potentially amplifying your savings.

An exciting development has been the introduction of specialist tariffs offering electricity rates as low as 15p/kWh specifically for powering heat pumps. At this rate, you could see your heating bill slashed by half compared to an oil boiler – a compelling incentive to make the switch.

Chart: Fornax Energy, Data: Evergreen Energy

Clean, carefree comfort

Heat pumps aren’t just more economical to run - they’re also safer, cleaner and offer better home comfort. 

Heat pumps eliminate the need for fuel storage and scheduled deliveries. That means no more risk of leakages and damage to your property. No burning oil also means no fumes, so you can enjoy improved air quality and eliminate carbon monoxide risks.

Heat pumps also heat in a very different way to oil boilers, working best when they are left to provide a constant gentle heat (as opposed to boilers which cycle though high-temperature heating, overheating and cooling). This makes them better at maintaining a consistent and comfortable indoor environment throughout the year (typically 19-21 degrees all day and a few degrees cooler at night), which is of particular benefit to older homes where large fluctuations in temperature can leave them susceptible to condensation or damp.

So for the same price - or less - than what you would spend on heating oil, your home can be at a comfortable, stable temperature all year round. 

Oil storage - risky business you can do without

Having a massive tank full of oil in your garden isn’t on most people’s wish-list, but is an unavoidable reality for oil boiler owners. Oil tank owners are legally responsible for ensuring their system doesn't contaminate the surrounding environment. Failing to prevent an oil leak could lead to hefty fines or even prosecution – not to mention the cleanup costs that could stretch into tens of thousands of pounds. Most homeowners with oil tanks take out additional insurance to protect their property (and their bank balance) in the event of a leak.

Image: Make tank refills a thing of the past

With a heat pump there is no fuel storage, meaning that your oil tank will be decommissioned and removed as part of the upgrade process. This means in addition to reclaiming valuable outdoor space, you will be able to ditch the oil spill insurance and enjoy peace of mind knowing there’s no risk of environmental damage or the associated clean-up hassle! 

The most impactful change you can make for the environment

On top of being all-around better technology for you and your home, heat pumps have the added feel-good benefit of being the most high-impact change a homeowner can make for the environment. We probably don’t need to tell you this, but oil boilers are not a green technology! Each oil boiler emits 5.2 tonnes of carbon dioxide per year, on average. That’s the same as eight return flights from London to New York!

Heat pumps are a pure-electric system, making them as green as the electricity that feeds them. This is great news as the UK’s grid is one of the greenest in the world. Multiple providers offer exclusively green energy tariffs - if you switch to a heat pump on one of these tariffs, at a stroke you’ll reduce your household carbon emissions by a whopping 75% (the average amount of energy used for heating).

So what else do I need to know?

So we’ve covered the numerous advantages, but what do you need to keep in mind when upgrading to a heat pump?

The main consideration is the upfront installation cost, which can be higher than a boiler switch. This is often driven by wider upgrades of older components such as radiators and water storage tanks. However the good news is that most households can secure a £7,500 contribution towards their project from the government Boiler Upgrade Scheme (BUS), making the net installation cost of the upgrade likely similar to or less than a boiler replacement. There are also solutions such as Fornax’s subscription that can remove upfront costs entirely.

It is true that to get the most from a heat pump system, many homes would benefit from updating their radiators to modern units that are efficient at transferring heat to your home. Any competent heating engineer will be able to accurately measure and design for this, and you should view it as an opportunity to make an improvement to your home that will last for decades to come. You can upgrade your radiators from a single panel to double or triple panels to increase their surface area without taking up extra wall space. The good news is existing pipework is usually compatible, making the transition from an oil boiler relatively straightforward.

A common question is around the noise level of the outdoor heat pump unit. While heat pumps do produce some noise during operation, modern models are designed to be quieter, and proper installation can mitigate any potential disturbance. Typically you will experience a hum at a similar level to a fridge [5]. On the coldest of days, this might be closer to the sound of a microwave as the unit works harder. However remember that this is also situated outside - meaning it will sound even quieter to those indoors - and noise levels can be further reduced by installing sound-insulating enclosures.

The most important decision - and something we can’t stress enough - is to ensure you deal with an experienced, qualified heat pump specialist. This will ensure that not only do you get a system that is appropriate for your home and its specific needs, but that you enjoy reliable and efficient heating performance for many years (at Fornax, we guarantee all of our systems for the life of your contract as standard).

Don’t get stuck in the past - make the switch today

If you're considering replacing your oil boiler, air-to-water heat pumps offer a superior and future-proof solution. With their potential for substantial cost savings, improved energy efficiency, practical benefits, and environmental advantages, they are a smart choice for homeowners looking to upgrade their heating systems. Plus for a limited time, most households can secure a £7,500 contribution towards their project from the government. You’ll also be beating the rush - it’s widely expected that oil boiler replacement will be banned entirely in the coming years, which is expected to increase wait times for the best heat pumps and installers! This is especially beneficial if your current oil boiler is nearing the end of its life and will need to be replaced in the near future anyway.

Don't let the misconceptions deter you – a heat pump is the best choice for the vast majority of homes. Seek professional advice from a heating specialist (who is familiar with heat pumps) and explore the options available for your home. By making the switch to a heat pump, you'll not only live in a more comfortable home and save money in the long run, but will also contribute to a cleaner and more sustainable future.

Embrace the benefits of this innovative technology and experience the comfort and convenience of efficient, low-maintenance, and eco-friendly heating for years to come!

If you’re interested in a hassle-free journey to the next level of home comfort, get in touch with our clean heating experts today.