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23 Nov 2020

Boilers vs Air Source Heat Pumps, which is cheaper?

By Ruby
  • Read time: 3 minutes
The use of renewable energy sources is has increased in popularity as people develop interests in nontraditional heating systems.

Now, why is that so? The rationale behind today’s hike in the popularity of heat pumps is that they are very energy efficient.

In other words, they play a significant role in reducing the cost of energy bills as they use less energy during functioning. Some people believe that specific warming systems are better than others. And this depends on one’s desires, preferences, and, more importantly, your budget.

Are you wondering which one is cheaper between the heat pump vs boiler? If yes, then you are surfing into the right site. This argumentative discussion will help you find the answers you’re looking for.

What is a boiler?

Worcester Bosch boiler

To begin with, a boiler refers to a heating device equipped with a sealed chamber. The chamber usually has a liquid-based solution or steam water. A variety of sources of energy used include oil, wood, gas, electricity, or biomass. They help heat the water-based solution in the chamber to a predetermined temperature to generate heat and hot water.

Typically, most homes in the UK rely on boilers for their domestic needs for cooking and hot water. Besides, boilers are available in different types depending on the type of coolant used.

Things to consider when choosing a boiler:

  • Power output (rated power the unit provides)

  • Efficiency rate (cost of operation)

  • Type of coolant used

  • Coolant’s operating temperature

  • Coolant’s operating pressure

  • Hydraulic resistance

What is an air source heat pump?

Vaillant aroTherm

A heat pump tends to be quite a complex device when compared with a boiler. However, its functioning involves mainly the use of a pump for generating heat for home use. Its operation depends on the absorption and transfer of a specific amount of thermal energy from air or underground sources to the pump’s coolant. After that, the refrigerated liquid or the coolant gets compressed to a higher temperature that can heat water.

The good thing with heat pumps is that they need a little amount of electricity to run. Besides, they can extract heat energy from the air or underground even when the temperatures fall as low as -15°C. Therefore, there’s no doubt that you’ll receive hot water and adequate warming all year round.

Looking for the best air source heat pumps? Consider picking the Daikin Altherma as they provide highly energy-efficient units. Another excellent choice you can buy is the Mitsubishi Ecodan and Vaillant aroTHERM.

Things to consider when choosing ASHP:

  • Installation costs

  • Pump’s refrigerant

  • Amount of power output

  • It’s technical features and rating

  • Warranty information

How it works

Heat pump vs Boiler: Which one is the best for your home?

Basically, a heating system you choose should rely on your home and lifestyle desires. As for our case, we have two options to choose from: the oil boilers and air source heat pumps. Their features and benefits will play a key role in determining which one is ideal for your home.

When it comes to relating the boilers and air heat pumps, the latter is the winner. In other words, most traditional boilers tend to waste about 25 to 50% of the energy used. As for modern boilers, they only waste about 8% energy. So, if you are into boilers, consider the modern ones to lower carbon dioxide emissions.

Air source heat pumps can be 350% efficient, which is up to 4 times than boilers. The reason is that ASHP uses significantly less electricity to generate an incredible amount of heat for home use.

A typical boilers can work effectively for about 8 to 12 years as long as it gets serviced yearly. On the other side, the air source heat pump has a lifespan range of 15 to 25 years. Plus, they have minimal movable parts that may break.

Space required
An air-source heat pump requires outside space for installation. It often has an outdoor unit sized like a washing machine. Those with heat exchanger tend to be larger than an average boiler hence occupies larger space. Oil boilers are relatively compact. Thus, they require less space to install.

Cost of installation
Installing a boiler is much affordable than even buying an air source heat pump. Averagely, it can cost up to £2,500, including labour costs. If you relate this to the cost of about £8,000 to £15,000 for an air source heat pump, installing a boiler is attractive. However Renewable Heat Incentive (RHI) funding coupled with the Government's Green Home grant scheme can quickly even this out.

Operating costs
An air-source heat pump is incredibly efficient as it uses less electricity, and thus the operating costs are comparable. On the other hand, boilers may be quite hard and costly to operate due to the increasing fossil oil prices.

Boilers require annual servicing by a registered expert for it to run flawlessly and safely. But air source heat pumps don’t need yearly servicing as they have fewer moving parts. However, you can conduct regular checks by an expert to keep it on track and service more effectively and efficiently.

Impact on the environment
The most significant advantage of using air source heat pump is that they don’t give carbon dioxide emissions while operating like boilers. ASHPs use less electricity to run, and their efficiency makes them environmentally friendly.

Dakin heat pump oudoors

Heat pump vs boiler: Who's the winner?

Deciding between a heat pump and a boiler depends on your desires and budget. In terms of cost, heat pumps require lump-sum amounts of money to install. Still, the maintenance and operation costs are incredibly low.

With boilers, the initial cost for installing is incredibly low. Yet, you’ll have to perform regular checks, servicing which can be costly. Plus, fossil fuel prices continue to increase, making it quite expensive to maintain your boiler. So, depending on your spending capability, you can decide which one is best for you.

Air source heat pumps are remarkably efficient up to 4 times than oil boilers. Suppose you are looking for the best unit. In that case, you may consider the best options, such as units from Daikin Altherma, Mitsubishi ecodan, and Vaillant aroTHERM. They are reliable and guarantee you cleaner energy for your home throughout.


Written by Ruby

Writes blogs about EV charging and climate solutions for 50five.