A major upside of heat pumps is demolishing your house and starting over. New rads, anyone?
- Heat Pumps with Radiators Key Points:
- What is a Heat Pump, and Can It Be Used With Radiators?
- What is a Heat Pump?
- Can Radiators Be Used with Heat Pumps?
- What Radiators Can Use a Heat Pump?
- Do I Need to Get New Radiators Installed?
- Radiators Vs. Underfloor Heating
- What About Using Radiators and Underfloor Heating?
According to the Heat Pump Association, the number of heat pumps almost doubled in 2021 alone, and the government plans to roll out more than half a million heat pumps annually by 2028.
With the rise of heat pumps, households have many questions, such as whether they work with radiators.
In this guide, we’ll answer this question in detail and discuss the main alternative to radiators – underfloor heating and how this method can also work with heat pumps in some cases too.
Let’s dive in!
Ready to make your home more energy-efficient and cut down on your heating bills? Get a heat pump quote today from our trusted partners at Heat Geek here.
Heat Pumps with Radiators Key Points:
You can use radiators with heat pumps.
However, your current radiators may not be suitable.
You may need to replace your current radiators with larger units.
It’s also possible to use underfloor heating combined with radiators.
A heating engineer will be able to help you ascertain if you need new radiators or not.
What is a Heat Pump, and Can It Be Used With Radiators?
Air source heat pumps can be used with radiators, but often, new, larger radiators are required for the system to heat a home adequately.
This is due to heat pumps operating at a lower flow temperature than traditional gas boilers, and so they require a larger overall radiator surface area in order to sufficiently heat a home.
Heat pumps can also be used with underfloor heating too, but this is typically impractical and expensive to install in existing homes.
What is a Heat Pump?
With that said, what exactly is a heat pump?
In contrast to alternative heating solutions (e.g. a gas boiler), a heat pump absorbs heat energy from the external environment and transfers it into your property.
Heat pumps require electricity to work and can provide hot water for heating and direct use, just like a boiler. However, it should be noted that there are many types of heat pumps available.
In short, the two primary options are ground-source and air-source heat pumps, with the former harnessing solar energy stored in the ground or water and the latter being used to capture heat from the outside air.
Can Radiators Be Used with Heat Pumps?
As touched on, it is possible to use radiators with heat pumps.
However, often the radiators will need to be replaced with larger units to provide a greater surface area.
This is due to heat pumps operating at a lower flow temperature than boilers, and so they typically require a larger overall radiator surface area in order to sufficiently heat a home.
Therefore, you may find that you’ll need larger radiators in order for a heat pump to do its job properly.
Whether or not you will need larger radiators will depend on a variety of factors, however, there are ways of determining this with the help of a qualified heating engineer.
While underfloor heating is one option, many households prefer to continue using radiators to avoid the disruption and cost of an underfloor heating installation.
Heat pumps transform cold air into hot fluid as a means of generating heat.
However, the hot fluid must be used to give off heat within your home (following distribution through the pipework).
As a result, radiators are one of two options for releasing this heat and warming up spaces throughout your property.
Reside in the UK and wondering if a heat pump is right for you? Check out our complete analysis where we asked - are heat pumps worth it?
What Radiators Can Use a Heat Pump?
While heat pumps do work with radiators, they can only be used with certain radiators including cast iron, aluminium, or steel panel radiators.
What’s more, radiators used with a heat pump generally need to be larger than those required for a gas-based central heating system.
In fact, heat pump radiators are usually 2.5x the size of standard radiators that would be used if you were to have a gas boiler.
Of course, the exact sized radiators needed would vary, so be sure to consult with a qualified heating engineer to determine what size radiators you’d need for your home and the specific heat pump you have in mind.
Moreover, aluminium radiators are arguably the most suitable of all (as far as materials go). This is because aluminium radiators are very conductive.
Indeed, they are more conductive than other population heat pump radiators like cast iron or steel units.
With a particularly high level of conductivity, aluminium radiators can help maximize the speed at which your rooms will heat up.
Ultimately, regardless of what material you prefer, it’s essential that you have a heat pump and household radiators that match and work well together.
Watch Our Air Source Heat Pump UK Case Study in the video below:
The reason heat pumps require larger radiators is to ensure that you get a flow temperature suitable for a heat pump installation.
This is another argument in favour of underfloor heating as a popular alternative to using radiators with a heat pump, but more on that shortly.
Beyond that, the radiators chosen must be suited to low-flow temperatures.
Heat pumps generally require a flow temperature ranging from 40 °C to 50 °C, although this can reach as high as a 55 °C requirement.
In contrast, radiators used alongside a gas boiler would need a higher flow temperature, mostly ranging from 65 °C to 70 °C.
This is because gas boilers need to heat your water to a significantly higher temperature in order to warm a property to a sufficient degree.
With a lower flow temperature, the surface area needed to heat a household goes up, thus this explains why a heat pump would need larger radiators in order to meet your home’s heating demands.
As you can tell, ensuring you have the right radiators to go with a heat pump (assuming you don’t opt for underfloor heating instead) is essential.
Do I Need to Get New Radiators Installed?
If you already have radiators installed along with a gas-based central heating system, there’s a very good chance you’ll have to get new, larger radiators installed in their place in order to make effective use of a heat pump.
Otherwise, you run the risk of having a poorly heated home while having wasted thousands in the process.
If your heat pump were to use radiators that are not large enough to deal with the low flow temperatures, your heat pump system would end up with a low Coefficient of Performance (CoP) rating than would be the case if it was used with more suitable radiators.
Ultimately, a low CoP would mean poor energy efficiency, higher energy usage, and, presumably, higher energy bills.
Of course, you should note that it may be possible to keep some of your existing radiators, depending on their size and how easy it is to heat the specific rooms each radiator is in.
Check out our review of the best heat pump brands of the year to find out which models are most reliable.
Radiators Vs. Underfloor Heating
So, ultimately, how do radiators and underfloor heating compare when it comes to using either of these options with a heat pump?
Underfloor heating is likely to be more energy efficient than using radiators.
In addition, underfloor heating can be installed underground and therefore be out of sight and out of mind.
In contrast, opting for larger radiators could act as an eyesore and negatively impact on the aesthetic of rooms throughout your property.
With that being said, there are still plenty of arguments for using radiators. Firstly, not all homes are suitable for underfloor heating.
Of course, some homes won’t be suited to either a heat pump or underfloor heating installation.
However, if your property can have a heat pump added but not underfloor heating, then radiators would be your only choice.
Beyond that, radiators may be preferable due to the cost difference between their installation and that of underfloor heating.
Depending on the type of underfloor heating system you opt for and whether the system is being installed as part of a new build, you’d likely end up paying anywhere from £3,000 to £9,000.
On the other hand, if you were to have, say, ten large radiators installed, your bill might come to £2,000 to £5,000 in total.
As you can see, there’s a good chance that opting for radiators would end up cheaper.
What About Using Radiators and Underfloor Heating?
Depending on your budget, preferences, and the suitability of your home to a large underfloor heating system, you may be curious to know whether you could take a hybrid approach.
In this scenario, you could have a relatively small underfloor heating system installed under some sections of your home and then use some large radiators to heat other rooms.
For instance, you might opt for underfloor heating as the primary form of heating on the ground level of your home, while using radiators to heat your upstairs rooms.
A suitable heat pump could be used to provide the required energy to both the radiators and your underfloor heating.
However, there are some potential issues with going for a hybrid solution.
One problem is that there would likely be a delay between the time your ground-level underfloor heating has warmed up to a sufficient level and the time that your upstairs radiators have caught up.
Again, it's always advised to consult a qualified heating engineer to determine whether your property would suit a combination of radiators and underfloor heating.
After all, you’d need to hire a professional to install the heat pump and radiator or/and underfloor heating when required.
Interested to learn how heat pumps compare to gas boilers? Check out our complete heat pump vs gas boiler guide.
Get a free quote for a hybrid heat pump today
Use our free quote tool, and we could be fitting your new hybrid system tomorrow.
Why choose Heatable?
Gas Safe installation within 24 hours.
Thousands of happy customers – an average score of 4.9 on Trustpilot (that’s better than the market leader).
Price match guarantee – if you find a cheaper quote, we will match (must be like for like).
Multiple payment options – interest free available.
10 year guarantee.
Fixed price guarantee – no hidden costs.
Save your quote until later.
Heat Happy.
