How To Adjust Water Temperature On Boiler

A recent written report by the Heating and Hot Water Council (HHIC)* plant that households can relieve effectually half dozen-viii% on their gas bill just by turning down the heating flow temperature on their condensing combi banality. To be clear, this is not turning down your thermostat.

In this guide we help you lot sympathize how running your banality at a lower temperature can reduce your energy consumption, whether you have the right sort of boiler to reduce the catamenia temperature and how to exercise information technology. Nigh boilers run at 10-25% under their A-rated efficiency.

New how-to video and illustrated leaflet now available: if you prefer to lookout man a video or request a free PDF leaflet that you can print off and/or e-mail to others you tin exercise then via our dedicated Mission page.

What does 'turning downwards the flow temperature' mean?
What blazon of boiler practise I demand?
How exercise I reduce the flow temperature?
What is the correct condensing boiler temperature setting?
Tin I use trial and error?
Will I detect any changes in my heating system?
What if I have a health condition?
Where tin can I get more assistance with this?
Why have I non been advised about this earlier?
Is there anything else I tin do to improve efficiency?
Can I adjust the hot h2o temperature down in the same way?
I take a hot water cylinder, what exercise I do?
Test if yous are ready for a rut pump?

1) What does 'turning down the flow temperature' mean?

Well-nigh gas boilers are set to operate at what is chosen lxxx/60 flow and return temperatures. This ways the boiler heats up the water it sends around your radiators (called 'the flow') to 80°C. The water returns to the boiler later travelling around all your radiators (called 'the render') at lx°C, having given off 20°C to the room.

However 80/lx menstruum and return temperatures are too high for a condensing gas banality to achieve the 92% efficiencies shown 'on-the-box'. Condensing boilers only have the potential to reach these higher efficiencies; in other words they are not A-rated out of the box.

The installer must reduce the menstruum temperature to give the boiler a adventure to run in what is known as 'condensing mode' equally much as possible. This is when it tin can recover the heat that was previously lost through the flue on sometime style boilers.

At 70/50°C the boiler will start to operate in condensing mode. Only when the flow and return temperatures are 65/45°C or lower will the boiler recover enough heat to achieve its efficiency potential.

2) What type of boiler do I need?

You lot will need to take a condensing combi boiler, i.e. a boiler that produces your heating and hot water. You will take a combi boiler if you do not have a hot h2o cylinder. It will definitely be a condensing boiler if it was fitted in the last sixteen years. A condensing boiler will too have a white piping that runs to an inside or outside drain.

What if I accept a hot h2o cylinder? Communication is different for boilers that work with a hot h2o cylinder. See section 12 beneath.

3) How practice I reduce the flow temperature?

If you have a condensing combi banality you can reduce the heating flow temperature on the front of your boiler. To exist clear this is not your room thermostat, this sets the menstruation temperature for the boiler. The way in which y'all adjust the catamenia temperature and the brandish information available varies a great deal. Three common are examples are given below:

1 or two dials

Most combi boilers have ii dials: 1 for heating (unremarkably with a little radiator icon over it) and one for hot water (with a picayune tap icon). Some only have 1 dial but it is normally for the heating menstruation temperatures. We've had lots of feedback on dials that do not provide the actual temperature setting. Some are numbered 1-6, some take dashed lines and others a curved line of increasing thickness. Some boiler manuals do provide additional information. If you take to piece of work it out manually, then as a guide most boilers have flow temperatures that operate between 30°C-fourscore°C. Which means 55°C volition exist about one-half way or the No. iii. We suggest setting to No.four to begin with or simply after the one-half way mark. If there is a 'e' on the punch (not always present), set up information technology to that. Information technology stands for 'economic system' and will be around 65°C, so ready just below. NB nosotros are not adjusting your flow temperature for hot water (with tap icon)- you lot should leave this at 60°C.

Dials with digital displays

Some boilers have a dial but the figure will appear in the digital display. Turn the punch downward until you lot accomplish 55-60°C. NB that the boiler may non operate at the temperature, information technology will target that temperature but reduce further when not needed. Our communication is not to get also distracted by what it does after. NB we are non adjusting your menstruation temperature for hot water (with tap icon)- you should go out this at 60°C.

Digital displays with up and down buttons

New boiler models have digital displays with up and down button then you can hands arrange the menstruation temperature and the figure will show in the digital brandish. NB we are not adjusting your flow temperature for hot water (with tap icon) you should exit this at 60°C.

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4) What is the correct condensing boiler temperature setting?

The correct temperature setting for heating is 'every bit depression as possible'. Boilers can commonly operate between 30-fourscore°C flow temperatures. They start to accomplish their higher efficiency figures at 45°C menstruation temperature, but that can be likewise low for older backdrop.

Ultimately how depression you lot can plow your flow temperature downwards will depend on the size of your radiators, how well insulated your home is and your thermostat temperature.

Lower menses temperatures need more surface surface area of radiator to meet your desired room temperature; hence why we need much larger radiators for an air source heat pump. The good news is that most radiators are bigger than they demand to be as the industry has sized based on guesswork or used basic online calculators that well-nigh e'er overcompensate. Nosotros recommend trying it at 60°C. If you lot have a home congenital later on 2010, try fifty°C.

For homes with modern double glazing, cavity walls and good levels of loft insulation you should exist able to drop your flow temperature down with no affect on comfort. Even older homes, particularly terraced houses, will be able to exercise this if they have been modernised and draft proofed.

5) Can I use trial and error?

Yes yous tin can. Without an authentic rut loss calculation and radiator sizing do, it will exist a matter of turning down the menstruum temperature and testing information technology to see if your house stays warm. You can turn it down piffling by trivial, or plough information technology downward a lot and notch it dorsum upwardly if it doesn't seem warm enough. Information technology may be that you can plow information technology down to below 60°C for most of the year but nonetheless need to notch it upwards in really cold conditions.

vi) Will I notice any changes in my heating system?

Yeah. Your radiators will not feel then hot. This is a sign that the system is running a niggling cooler, which is what you are trying to achieve. Providing your home does not feel cold and y'all do not experience cold, the banality and system are working correctly and more than efficiently.

If you have your heating programmed to come on for a very limited corporeality of time, you may notice that it will have longer for your domicile to heat upwardly. Many households are accustomed to short heat upwards times because they run and so hot. Lower flow temperatures will mean slightly longer heat up times.

For those that have the heating on much of the day, y'all volition motion to lower temperatures for longer periods which will have a positive affect on fuel bills.

7) What if I have a health status?

We would caveat the to a higher place communication for those with health atmospheric condition. Staying warm is very important and we would non wish y'all to risk your well beingness by adjusting your heating system on a trial and error basis.

eight) Where can I get more than help with this?

Try our How-To video which shows how to turn the menses temperature downward on different types of combi boiler. For more information on your boiler you can wait in the instruction manual. Yous can usually find your manual on-line if you search for the make and model of your boiler. To be totally sure you take the right manual, find the boiler's 'GC' number. Every banality has one and its usually on the boiler's data-plate. It will outset with GC followed by a 7 digit number.

Alternatively you can ring the manufacturer'south technical helpline for customers. They will need the model or preferably the GC or serial number to assistance you with your particular boiler.

You can as well inquire your installer when you next have the boiler serviced. NB not all installers are familiar with condensing boiler technology, just should exist able to assistance with this part.

nine) Why have I not been brash about this before?

A vast skills and knowledge gap (that dates back to 2005 when condensing gas boilers become mandatory) means 99% of installers do not sympathise how condensing gas boilers piece of work and therefore cannot set them up to run as they were designed to. Installers take been let downwards then have UK households. Nosotros accept just not benefited every bit much as we should have from this bound frontwards in boiler efficiency.

Part of our work is to educate households on their heating systems and help them get college efficiencies from their existing boilers. The over-replacement of boilers is a trouble in the UK. We want to see more than existing boilers running optimally with modest changes that reduce energy bills and our carbon footprint. A 15% efficiency improvement across all UK households is enough to heat every habitation in Wales for a yr.

Finding skilled installers is besides a struggle. We have spent a lot of time building a highly competent installer network**.

10) Is there annihilation else I tin can do to meliorate efficiency?

Yes lots. Lowering the period temperature is simply stride ane. Most boilers are running 10-25% nether their A-rated efficiency due to wrong set. A number of changes tin can be fabricated to whatever boiler and heating system to tap latent efficiency. We help households invest in low toll efficiency measures to their existing banality and heating system to harness untapped efficiency. To be clear we rarely advocate replacing a working, condensing boiler. We offer i-2-1 assist via our pioneering efficiency services to provide a bespoke specification for your boiler and system, visit How we piece of work for more.

11) Can I adjust my hot water temperature dial in the same way?

We propose non to adjust the hot water temperature (with tap icon) below 60°C. It is important that your pipes, taps and shower heads are kept complimentary of legionella.

12) I take a hot water cylinder, what practice I practice?

If you take a hot h2o cylinder, you volition take either a 'system' boiler or a 'conventional' banality (aka heat-only or regular boiler) with a 'vented' or 'unvented' hot water cylinder. The HSE state that hot h2o must be stored in the cylinder at 60°C to kill legionella bacteria (which tin be fatal for humans), which means menstruum temperatures should be 70°C to compensate for heat losses in the transfer of hot h2o to the cylinder.

In nearly all households the boiler can only supply 1 temperature, which has to exist the college temperature for hot water safety, i.e. 70degC. It is a distressing fact that if you have a hot water cylinder the boiler it will almost NEVER condense! In other words, most boilers that work with a hot cylinder are no where almost efficient.

What is the solution? The boiler needs to be prepare with split heating and hot water temperatures, a depression efficient temperature for heating and a high rubber temperature for hot water. Adapting your boiler so it tin supply a lower flow temperature for heating (that you can adjust) requires banality-specific advice and some minor works to your system. Nosotros can provide the correct advice for your boiler via our efficiency audit service.

To be clear, this arroyo does not suggest y'all throw out your hot water cylinder in favour of a combi. Equally nosotros transition to low carbon heating solutions we volition need our hot water cylinders again. Rather the boiler needs to be set upward correctly with the cylinder to get the best efficiencies for heating. Get to our latest web log on keeping your gas boiler and making information technology more efficient.

xiii) Test if you are ready a oestrus pump

If you tin run your heating system at 45°C then your system will work with a heat pump without modification. If you have underfloor heating in large parts of your home; a home built in the concluding 10 years; or an older home that has been heavily insulated there is a good take a chance y'all can run your heating system low enough.

WARNING: many new build homes use 'microbore' pipework (instead of standard 15mm pipework you lot volition accept 10mm or even 8mm pipework) and it maybe too small to cope with lower flow temperatures. There are exceptions when it tin can piece of work however.

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