Saving on your central heating boiler: 7 tips that make an immediate difference
By Laurens Arends · updated 19-09-2026
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Saving on the energy consumption of the central heating boiler
According to Milieu Centraal on average 72% of gas consumption goes to space heating. With an annual consumption of 1.200 m³, that is about 864 m³ of heating gas. The settings of the central heating boiler, radiators and thermostat therefore have a great deal of influence on how much gas you use.
The amounts below are our own calculations with € 1,52 per m³ of gas (in line with 2026 price levels). Do not simply add the amounts together. Measures can overlap and your saving depends on the insulation, the outside temperature and the current settings.
| Way to make your central heating boiler more economical | Indicative saving per year | Effort |
|---|---|---|
| Lowering heating water from 80 to 60 °C | € 91 to about € 120 | Low |
| Replacing comfort mode with eco mode | About € 23 | Low |
| Hydronically balancing the central heating installation | About € 131 to € 197 with a poorly balanced installation | Medium |
| Insulating ten metres of heating pipe | About € 46 | Low |
| Bleeding, topping up and maintenance | No reliable amount. With a properly working installation, the direct saving may be negligible. | Low |
| Replacing an old central heating boiler | About € 190 when replacing an old conventional or vr boiler | High |
| Smart placement of the central heating boiler | No reliable fixed amount | High |
Set the heating water to 60 °C
Many central heating boilers have a maximum flow temperature of 80 °C. In a reasonably insulated home, according to Milieu Centraal, 50 or 60 °C is often more than enough. At a lower temperature, cooler water returns to the boiler. As a result, more water vapour condenses from the flue gases and the hr boiler makes use of more heat. HIER calculates with a gas saving of about 60 m³.
That is 60 × € 1,52 = € 91 per year. Urgenda names about € 120 as an achievable saving. A modern modulating boiler that already runs at a low temperature will save less. Only lower the temperature of the heating water for the radiators. Keep hot tap water at a minimum of 60 °C because of legionella. If the house does not get warm on cold days, then raise the heating temperature step by step to 65 or 70 °C.
Set the hot water function to eco mode
In comfort mode, a combi boiler keeps the heat exchanger warm. As a result, hot water comes out of the tap more quickly, but the boiler also uses gas when nobody is using hot water. In eco mode, heating only starts when you open the tap. According to Milieu Centraal, eco mode saves on average about 15 m³ of gas per year.
Our calculation comes to 15 × € 1,52 = € 22,80 per year. You sometimes have to wait a few seconds longer. The gas saved normally outweighs the little bit of extra cold water. If you often use hot water throughout the day, the saving is smaller.
Have your central heating hydronically balanced
With a poorly balanced installation, radiators close to the boiler get too much hot water and radiators further away get too little. You can recognise this, for example, by a hot living room and an attic radiator that hardly gets warm. Turning the thermostat up then makes the living room even warmer. In this case, hydronically balancing the central heating is advisable.
According to Milieu Centraal, hydronic balancing ensures that every radiator gets the right amount of water. The Consumentenbond names a possible reduction in energy use of 10% to 15% with a poorly balanced installation. With 1.200 m³ of gas per year, we calculate with 864 m³ for heating. The saving is then 86 to 130 m³, or € 131 to € 197 per year. If the installation is already reasonably balanced, you will of course save less with hydronic balancing.
Hydronic balancing is not the same as bleeding. When bleeding, you remove air from radiators. With hydronic balancing, an installer limits the water flow per radiator and adjusts, among other things, the pump, flow temperature and boiler control. According to Vereniging Eigen Huis, the costs of hydronic balancing in 2026 are typically between € 500 en € 1.000. In the calculation example, the simple payback period is therefore between about 2,5 and 7,6 years. That is a good payback period to justify the investment.
Insulate heating pipes in unheated rooms
Heating pipes in a cold attic, in a crawl space or in an unheated storage room give off heat in a place where you do not need it. According to Milieu Centraal, twenty-millimetre-thick pipe insulation saves about 3 m³ of gas per insulated metre of heating pipe per year. If you insulate ten metres, you indicatively save 10 × 3 = 30 m³ of gas.
At € 1,52 per m³ that is € 45,60 per year. According to Milieu Centraal, the material costs about € 1 per metre. Above all, insulate the flow and return pipes in unheated rooms. Pipes in a heated room do not give off their heat entirely for nothing and help warm the room. Any saving there will therefore be much smaller.
Bleeding, topping up and maintenance
Bleeding and topping up keep the central heating installation working well. In theory, a well-maintained central heating installation uses less, but concrete figures are not available. If your installation is already working normally, the financial benefit may be negligible. In any case, check the water pressure a few times a year and follow the range in the manual of your boiler. Do not automatically use 1,8 bar as a universal standard. The correct pressure depends on the installation and the difference in height in the home. Bleed an older installation when radiators gurgle or stay cold at the top.
If the pressure keeps dropping, have it checked whether there is a leak or a defective expansion vessel. The Rijksoverheid advises having a gas combustion installation checked at least once every two years. The manufacturer will probably prescribe annual maintenance. Work on the boiler, burner or flue gas outlet may only be carried out by a certified company.
Replacing an old central heating boiler
You can make an old central heating boiler more economical, but a modern boiler can probably still deliver much better performance. In that case, choose an hr boiler. An hr boiler recovers heat by letting water vapour from the flue gases condense. The gain compared with another hr boiler is usually much smaller than compared with an old conventional boiler.
When choosing a new hr boiler, you look at the efficiency. This is often indicated as an HR value, for example HR107. This means that the boiler has an efficiency of 107%. The Consumentenbond emphasises that this percentage is calculated using the lower calorific value, in which the condensation heat is not included in advance. The voluntary Gaskeur label from Kiwa also states the CW class. CW says how much hot water a boiler can deliver, not how much gas you automatically save.
According to research by the Consumentenbond, a central heating boiler lasts on average about fifteen years. The average payback period with an average purchase price of € 2.100 (incl. installation) and an indicative saving of € 190 per year is about eleven years.
Alternative: renting an economical central heating boiler
It is of course true that a new central heating boiler is fairly expensive. As a result, saving with a new central heating boiler is not within everyone’s reach. That is why many energy suppliers offer the option of renting a central heating boiler. The rental price is often fairly low and the maintenance costs are usually included in the price (for a certain period).
A breakdown service is also often included. Always pay attention to the terms and conditions, though, because cancelling is not always possible quickly or easily. Also bear in mind that in the long term renting can be more expensive than buying.
Smart placement of the central heating boiler
The placement of the boiler also plays a role in optimising efficiency. The further the central heating boiler is placed from the radiators and taps, the more pipes are needed and the more heat can be lost in these pipes. That is why it is advisable to keep the pipes as short as possible and to place the central heating boiler centrally in the home. An additional advantage is that hot water is available more quickly.
Want to save more than with boiler settings alone? See all saving tips and the measures to save gas structurally.
Frequently asked questions about saving on the central heating boiler
Which is better: a higher or lower flow temperature?
A lower flow temperature is more economical as long as the home gets comfortably warm. According to the Consumentenbond, the condensing principle of an hr boiler works best when the return water is colder than about 55 °C. Start with 60 °C and only raise the setting if the radiators give off insufficient heat in cold weather.
Can the hot water from the central heating boiler be lower than 60 degrees?
The heating water for radiators can often go to 60 °C or lower. Keep hot tap water at a minimum of 60 °C to limit the risk of legionella growth.
How do you prevent frost damage to the central heating installation?
Do not switch the boiler off completely during frost, because the built-in frost protection only works if the appliance has power and gas. Use the frost or low setting from the manual, insulate pipes in cold rooms and shut off outdoor taps.
What is the lifespan of a central heating boiler?
According to a survey by the Consumentenbond among more than 7.000 households, a central heating boiler lasts on average about fifteen years. For half of the participants, the previous boiler lasted at least fifteen years and fewer than one in ten boilers was replaced within ten years. Maintenance and water quality influence the actual lifespan.
How much energy does a central heating boiler use?
This varies greatly per home. According to Milieu Centraal, on average 72% of household gas consumption goes to space heating. With 1.200 m³ of gas per year, that is about 864 m³ for heating, in addition to the gas for hot water and cooking. Milieu Centraal also calculates indicatively with about 240 kWh of electricity per year for the pump and electronics of a central heating boiler.