How to Change the Temperature Settings on a Vaillant ecoTEC Pro Combi Boiler.
- 5 hours ago
- 8 min read
The Vaillant ecoTEC Pro is one of the most popular combi boilers installed in homes across Liverpool, the Wirral, and the wider North West. It is a reliable, efficient unit that delivers both heating and hot water from a single compact system. But one of the most common questions we get asked at DD Wilson Gas And Heating Engineers is how to adjust the temperature settings. Darren Wilson (DD Wilson Gas And Heating Engineers Ltd, Director)
Whether you have just had a new boiler installed or have lived with your ecoTEC Pro for years, knowing how to control your hot water and heating temperatures puts you in charge of your comfort and energy bills. This guide walks you through every step, based on what our engineers explain to customers during handover on every job.
How to Change the Temperature Settings on a Vaillant ecoTEC Pro Combi Boiler - Vaillant ecoTEC Pro temperature settings
Why Would You Need to Change Your Boiler Temperature?
There are several practical reasons Liverpool homeowners adjust their boiler temperature settings. During the colder months, you might want your radiators running hotter to keep up with the draughty Victorian terraces and pre-war semis that are so common across areas like Aigburth, Allerton, and Crosby. In milder weather, you can bring the temperature down and save on gas.
Hot water temperature is another common adjustment. If you have young children at home, you might want to reduce the domestic hot water temperature to avoid any risk of scalding. On the other hand, if your showers feel lukewarm, bumping the temperature up a notch can make a real difference.
The ecoTEC Pro makes all of this straightforward through its built-in display controls. You do not need any special tools or technical knowledge.
How to Adjust the Hot Water Temperature
The hot water temperature on your Vaillant ecoTEC Pro controls how hot the water comes out of your taps, showers, and bath. Navigate to the hot water temperature setting on the boiler display. Use the up and down controls to raise or lower the temperature to your preferred level. Most homeowners find that somewhere between 48°C and 55°C works well for domestic hot water. Going too high wastes energy and increases the risk of scalding, while going too low can leave you with water that does not feel hot enough at the tap.
Once you reach the temperature you want, you will see a small tick icon in the display's corner. Press the tick to confirm your setting. Then press the back arrow to return to the main menu. That is all there is to it.
If you are unsure what temperature to set your hot water at, our team at DD Wilson are always happy to advise. You can get in touch or book a service, and we will check everything is set up properly for your household.
How to Adjust the Heating Flow Temperature
The heating temperature on a Vaillant ecoTEC Pro works slightly differently from the hot water setting, and this is where homeowners sometimes get confused. This setting does not control when your heating comes on or off. That is the job of your thermostat. This setting controls how hot the water flowing through your radiators actually gets.
The standard factory setting is usually 75°C, which is what most boiler engineers will set it to during installation. At 75°C, your radiators will heat up quickly, and your house will reach a comfortable temperature faster.
To adjust it, navigate to the heating temperature setting on the display, use the controls to raise or lower the value, press the tick to confirm, and you are done.
What Does the Heating Temperature Actually Mean for Your Radiators?
One thing worth noting is that 75°C refers to the water temperature inside the radiators, not the radiator's surface temperature. Your radiators will not reach 75°C to the touch, but the water circulating through them will be at that temperature. The radiator surface will typically be noticeably cooler than the water inside.
If you have young children and you are worried about them touching hot radiators, you can lower the flow temperature. The trade-off is that it takes longer for your home to heat up because the radiators are working at a lower intensity. For most households, 75°C remains the best balance between speed and efficiency.
If you are thinking about your heating system performance more broadly, it may be worth considering a central heating upgrade or a power flush to make sure everything is running as efficiently as possible.
Understanding the Pressure Gauge on Your Vaillant ecoTEC Pro
While you are adjusting your temperature settings, it is worth checking the pressure gauge on your boiler display. The ecoTEC Pro shows the system pressure as a bar reading with two dotted lines, one at the top and one at the bottom. You will notice that the gauge has a coloured section. This coloured area needs to sit between the two dotted lines. When the boiler is cold, the pressure should typically read between 1.0 and 1.5 bar. When the system heats up, the pressure will rise slightly, and that is perfectly normal. If the pressure drops below the lower dotted line, your boiler will go into safety mode and stop working. To fix this, you need to repressurise the system using the filling loop underneath the boiler. Open the valves slowly and watch the gauge on the display. Once the pressure sits comfortably between the two dotted lines, close the valves. You can find more details in our guides on repressurising a Vaillant boiler and how to repressurise a boiler generally. If your boiler keeps losing pressure regularly, that can indicate a leak in the system or a problem with the expansion vessel. In that case, it is best to call a qualified engineer to investigate rather than just topping it up repeatedly.
Turning Your Boiler Off When Going Away
If you are heading away on holiday and want to switch the boiler off completely, you can simply turn it off using the power button. When you return, switch it back on and let the system warm up for a few minutes before expecting hot water or heating.
During winter, however, be cautious about turning the boiler off entirely for extended periods. If temperatures drop below freezing, your pipes could be at risk. Most modern Vaillant boilers have a built-in frost protection mode that activates when the boiler senses the temperature dropping too low. Keeping the boiler on its lowest setting rather than switching it off completely can help protect your plumbing during cold snaps. We covered this in more detail in our guide to keeping your home safe in freezing weather.
Common Temperature Questions from Liverpool Homeowners
Should I Turn My Heating Flow Temperature Down to Save Money?
There has been a lot of discussion about running boilers at lower flow temperatures, typically around 55°C to 60°C, to improve condensing efficiency. In theory, a lower flow temperature means the boiler condenses more of the water vapour in the flue gases, extracting more heat from the same amount of gas.
In practice, this works best in well-insulated modern homes with larger radiators. Many older Liverpool properties, particularly the terraced houses across L8, L15, L17, and L18, have smaller radiators and less insulation, requiring higher flow temperatures to maintain a comfortable room temperature. If you turn the flow temperature down too far, you could end up with your boiler running for much longer to achieve the same result, which may not save you anything at all.
The best approach is to speak to a heating engineer who can assess your specific setup. Our team at DD Wilson can advise on the optimal settings for your home during a boiler service.
What Temperature Should I Set My Hot Water To?
For most households, between 48°C and 55°C is the sweet spot. The NHS recommends that hot water should be stored at 60°C to prevent legionella bacteria, but combi boilers heat water on demand rather than storing it, so legionella risk is significantly lower. A setting of around 50°C to 52°C gives you comfortably hot water without excessive energy use or scalding risk.
My Radiators Are Hot at the Top but Cold at the Bottom
If your radiators are not heating evenly, the issue is unlikely to be your temperature settings. Cold spots at the bottom of radiators usually indicate sludge buildup in the system. A power flush can clear this out and restore your radiators to full performance. We have a detailed post on power flushing and what to expect if you want to learn more.
If the radiators are hot at the bottom but cold at the top, that is usually trapped air, which you can fix by bleeding the radiator.
When to Call a Professional
Adjusting your temperature settings is something any homeowner can do safely. But there are times when you should call a qualified Gas Safe registered engineer:
If your boiler is displaying an error code or fault light, do not try to reset it repeatedly. Error codes are there for a reason, and repeatedly resetting can make underlying problems worse. Our post on resetting your boiler after a power cut explains the difference between a normal reset and a fault condition.
If the boiler is making unusual noises, keeps losing pressure, has a hot water temperature that fluctuates wildly, or you smell gas, you should contact a professional immediately. DD Wilson offers boiler repair services across Liverpool, the Wirral, and the North West, and we can usually attend the same day for emergencies.
Watch Our Video Guide
We have put together a short video showing exactly how to adjust the temperature settings on a Vaillant ecoTEC Pro. Darren from DD Wilson walks you through the hot water controls, heating flow temperature, pressure gauge, and how to turn the boiler off safely.
Watch the video: How to Change the Temperature on a Vaillant ecoTEC Pro
Frequently Asked Questions
What is the best temperature setting for a Vaillant ecoTEC Pro?
For hot water, most homeowners find 50°C to 52°C works well. For heating flow temperature, 75°C is the standard setting that suits most Liverpool homes. Well-insulated properties with modern radiators may benefit from lower flow temperatures around 55°C to 60°C, but this needs to be assessed on a case-by-case basis.
Can I damage my boiler by changing the temperature?
No. The Vaillant ecoTEC Pro has built-in safety limits that prevent you from setting temperatures outside the safe operating range. You can adjust the settings without any risk of damaging the boiler.
Why is my Vaillant ecoTEC Pro not reaching the set temperature?
If your hot water is not reaching the temperature you have set, this could indicate a flow rate issue, a problem with the plate heat exchanger, or limescale buildup. If your heating is not reaching temperature, you may have circulation problems or sludge in the system. In either case, it is worth booking a boiler service to investigate.
How often should I have my Vaillant ecoTEC Pro serviced?
Vaillant recommend an annual service to maintain your warranty and keep the boiler running efficiently. A professional boiler service includes checking all safety devices, cleaning components, and verifying that your settings are optimised for your household.
What pressure should my Vaillant ecoTEC Pro be at?
When cold, the pressure should be between 1.0 and 1.5 bar, sitting between the two dotted lines on the display. It will rise slightly when the heating is on, which is normal. If it falls below 0.8 bar, the boiler will enter safety mode and need repressurising.
Does DD Wilson install and service Vaillant boilers in Liverpool?
Yes. DD Wilson is a Vaillant Advance Master Tech installer, meaning our engineers are factory-trained to install and service the full Vaillant range, including the ecoTEC Pro, ecoTEC Plus, and ecoTEC Exclusive. We cover Liverpool, the Wirral, and a 40-mile radius across the North West.
How much does a Vaillant boiler service cost in Liverpool?
DD Wilson offers competitive boiler service packages. You can check our latest pricing on our service shop or call us on 0151 739 8945 for a quote.
Need Help With Your Vaillant Boiler? Talk to DD Wilson
DD Wilson Gas And Heating Engineers Ltd have been keeping Liverpool homes warm since 1998. As Vaillant Advance Master Tech installers, our Gas Safe-registered engineers (registration 583586) are factory-trained to install, service, and repair the full Vaillant range. With over 3,000 five-star reviews, we are the North West’s most trusted heating company.
Call us: 0151 739 8945
Gas Safe Registered 583586 | Read Our Reviews | Areas We Cover
Related Articles
DD Wilson Gas And Heating Engineers Ltd | Gas Safe Registered 583586 | 0151 739 8945 | ddwilson.com | Content created by Constellation Marketing Solutions | February 2026
