Radiator Installation Guide

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If you’re redesigning your home, or have recently moved to a new house and wish to redecorate, you will likely need to remove, rehang or even replace your radiators. Radiators are available in a wide variety of materials, designs, and finishes so you can pick and choose to match your interior décor. Changing older radiators to more efficient radiators can also help you to drive down energy costs around your home and do your part in protecting the environment. Whatever the reason for changing your radiators is – our guide will help you to complete the job as safely as possible. If you decide to find a plumbing company for help, we have also listed our top tips to find the right tradesperson. As qualified plumbing professionals, Perfect Plumbers can help you to remove and rehang all types of radiators around your home – give us a call for a quote!


How Do Heating Systems Work?

Before you start to remove and replace the radiators around your home, it helps to understand how the entire central heating system works. This will help you to maintain the system and also identify when a problem occurs. Central heating systems have largely replaced traditional wood and coal fires in domestic properties. The benefit of a central heating system over these traditional methods is that it can heat the entire household from one central place, instead of having fires in every separate room. The basics of a household central heating system are pretty simple, one central boiler, or an easily controlled gas furnace, heats water while an electrically powered pump distributes this heated water throughout radiators in each of the rooms. The Boiler The boiler is the most important part of the central heating system and generates the heat that keeps the rest of the house warm. The boiler is supplied with natural gas from a pipe connected to the main gas line outside in the street – this pipe provides a continual flow of gas to the boiler. To operate the boiler there is an electrical switch which opens a valve and lets the gas enter the sealed combustion chamber that sits within the boiler. The gas enters the chamber through a series of small jets and at the same time, an electric ignition system sets them alight. The gas jets are directed towards a heat exchanger that is connected to a pipe carrying cold water. The energy from the gas jets is transferred via the heat exchanger and warms up the water in the pipe. The hot water is then circulated through each of the hot-water radiators in the house, eventually returning to the boiler. As the water passes through the radiators, they release the heat to warm the rooms. However, by the time it reaches the boiler, the water will have cooled considerably, which is why the boiler continuously fires so that it can reheat the returning water. The water is pushed through the system with the aid of an electric pump, often located inside the boiler or very near to it. This is a sealed system to keep the water permanently inside, but it can be drained for maintenance work. The Thermostat Many central heating systems are manually controlled so that you have to switch them on and off again when you feel cold. These systems can be programmed to turn on at certain times of the day (such as first thing in the morning, and just before members of the household return after work) but they still require a manual trigger to turn them on and off. Some central heating systems though, are controlled using a thermostat, which is fixed in a certain room. The thermostat is a thermometer linked to an electric switch, so when it detects that the temperature has fallen below a specified amount it will automatically activate the switch to turn on the boiler. Once the thermostat detects that the room has reached the correct temperature it will once again activate the switch to turn the boiler off. The Radiators A simple radiator consists of a copper pipe that is bent in u-shape between 10-20 times to create a large enough surface area to heat a room. Standard radiators without a thermostatic control cannot operate at different temperatures, they are either on or off depending on whether hot water from the boiler is flowing through them or not. These radiators can, however, be switched on or off independently using the screw valve located at the bottom. Turning the screw-down will close the valve meaning the hot water will simply flow through the pipe at the bottom, by-passing the top part of the radiator completely. Turn the screw up to reactive the radiator and turn it back on. Thermostatic valves (also known as TRVs) offer more control over the temperature of induvial radiators within the heating system and help to reduce your energy consumption. With thermostatic valves you can set the temperature in some rooms to be warmer than those in others, so for example, during the day you might want to keep your living room warmer than your bedrooms. Thermostatic valves work by heating the radiators fitted with the valves as soon as the heating system is switched on. Once those radiators have reached the right temperature, they begin to switch off, so the boiler is required to fire less often. This in turn eventually brings down the temperature of the water running through the system. If the room with the thermostatic valves cools down too much, the valves open up again, triggering the boiler to fire more often and increase the temperature of the water running through the system. Combi-Boilers Gas combi-boilers work to provide heat and hot water on demand. To achieve this, combi-boilers usually have two heat exchangers that work independently of one another. One of the exchangers carries water through to the radiators whilst the other carries through to the hot water supply. When a hot tap is turned on, it opens a valve that releases water. At the same time, the boiler detects that a faucet is open and heats the water as it passes through. In most cases, central heating boilers will have to pause from operating the central heating while heating the water, as they cannot produce enough heat for both applications. Condensing Boilers In 2005, it became compulsory for all new gas boilers to be condensing boilers. Condensing boilers are designed to improve energy efficiency by converting water vapour condensation into heat, making more use of the fuel it burns. To check if you have a condensing boiler refer to the manufacturer’s handbook. Alternatively, you could check the flue terminal to see if it is plastic and whether white steam comes out of it when the boiler is turned on. The terminal is usually found on an outside wall not far from where the boiler is fitted. A condensing boiler has two internal heat exchangers to reduce the amount of heat lost from flue gases. The water vapour in the flue gases is allowed to cool enough so that it condenses and is then removed to a waste pipe through a condensate pipe. Condensing boilers also do not need a pilot light burning constantly, unlike non-condensing boilers. Condensing boilers only ignite using an electric spark when there is a demand for heat which reduces your energy bills and extends the life of the boiler. Boiler Efficiency Having an energy-efficient boiler can save you hundreds of pounds per year in energy bills. It is estimated in the UK that around 60% of your energy bill goes into heating your home. There are currently a couple of different systems in place to measure boiler efficiency, these are ErP, SEDBUK 2009, and SEDBUK 2005 all of which run off slightly different calculations. Every new boiler is given an ErP rating from A-G. ErP rates the boilers efficiency and most modern boilers will receive an A energy rating which means they are very efficient. The SEDBUK rating system stands for ‘Seasonal Efficiency of a Domestic Boiler in the UK’ and like the ErP system it rates boilers from A-G. A-rated boilers are over 90% efficient whereas G-rated boilers are below 70% efficient. The original SEDBUK 2005 rating is still commonly used by many manufacturers, but the 2009 rating is applied to newer ones. The SEDBUK 2009 rating gives each boiler an exact percentage score that is far more accurate than the 2005 and ErP rating systems.

Maintaining Your Central Heating System

To protect your central heating system from damage and to keep it running as efficiently as possible, you should take steps to maintain it. Making Your Boiler More Efficient To keep your boiler in good working order and to make sure you drive your energy costs down by keeping it efficient, here are some steps you can take.

  • Regular services. Schedule an annual service for your boiler with a Gas Safe Registered engineer. The engineer will check that the boiler is configured most efficiently and will remove any dirt or build-ups that could be hindering its performance. In rented properties, it is the landlord’s responsibility to ensure that a yearly inspection of the gas boiler is carried out.
  • Set your boiler efficiently. As the seasons’ change, so will the requirements from your boiler. Make sure your boiler is set for the right conditions and be careful not to set the temperature too high. A high temperature poses a risk from hot pipes, radiators and water especially for children, elderly people, and vulnerable people.
  • Hot water settings. Set the thermostat temperature in your water tank to between 55C and 60C and then adjust your boiler for efficiency. During the winter set your boiler to around 80C (do not go higher than this) and in the summer when you don’t need the heating, to around 60C.

Deep Cleaning Your System As your central heating system is used a magnetite substance can start to collect in the pipework and radiators. Also known as black sludge, it can cause the system to become clogged, making it inefficient and at risk of breaking down. There are products available that contain a cleaning chemical which, when added to your heating system, will break down and remove the debris that has accumulated. Feel free to reach out to us at Perfect Plumbers for advice on how often you should clean your central heating system. We’ll be more than happy to help! System Flushing Flushing your central heating system helps to remove all of the older contaminated water while cleaning your pipes, radiators and boilers at the same time. This helps to clear away any debris sitting within the system and fill it with fresh, clean water to keep it healthy and working efficiently. Perfect Plumbers can help you to safely flush your central heating system, contact us for a quote! Using Your Heating Timers Using your heating timers to effectively time when you need your heating on is a great way to extend the life of your central heating system and cut down on your energy bills. Think about when you are most likely to need the heating on, for example, first thing in the morning and the evening when you return from work. A boiler that is left running all day long is at risk of breaking down or needing parts replacing more frequently. Insulate Your Pipes Insulating your pipes is not only a great way of protecting them against freezing, but it can also keep the water warmer as it runs through them, for longer. This puts less stress on the boiler as it is not having to work as hard to keep the water at the right temperature. Again, it will also help you to cut down on your energy bills as the boiler is firing less often and using less gas. Monitor The Colour of The Pilot Light Checking the pilot light on your boiler can give a good indication of its health. A boiler that burns with a blue pilot light is burning fuel more efficiently and cleanly than those with yellow or orange flames. Pilot lights that burn yellow or orange are cooler than blue flames and indicate incomplete combustion. This can lead to soot, smoke damage and even harmful carbon monoxide emissions. If your pilot light is not blue, contact a plumbing professional (such as us here at Perfect Plumbers!) for advice. Monitor The Pressure If the water pressure within your heating system is too high it can put additional pressure on the pipes, valves and fittings. A domestic water system should have an ideal pressure of one bar and no higher than two bars. You will see the pressure indicated on the boiler and maybe a green triangle to show you where the right pressure mark is. If you notice that the pressure on your boiler is too low, you can easily recalibrate it yourself. Locate the tap under the boiler and refill it with water to re-pressurise the system. Fit Smoke and CO Detectors Smoke and carbon monoxide detectors are vital in any home with gas central heating. Carbon monoxide is an odourless and colourless substance that is highly poisonous. The only way carbon monoxide can be detected is by using CO detectors. Smoke detectors will also alert householders in the event of a fire and save lives. You should install smoke alarms and CO detectors on all levels of your home.

Finding the Right Radiator

When it comes to installing new radiators within your home, there are different styles, materials and colours to choose from. The most important thing to consider when choosing new radiators is how well they will heat your home. The heat output of a radiator is measured in British Thermal Units Per Hour (BTU/h) and a registered Gas Safe heating engineer can help you to work out the right BTU/h for each room. The location of the radiator within each room will also play a part in your choice of material and design. You will need to take into account how much space you have and the size of the room you need to heat. As a rule, the larger the radiator, the more heat it will give out. The radiator should be placed in the coldest part of the room, ideally beneath a window or on an outside wall. This is because cold air helps to push the warm air around the room. When choosing a radiator, you will also need to take a look at the existing pipework you have in place. A new radiator that is the same size or wider than your existing radiator can easily be installed into the same pipework, but a smaller size might require the pipes to be extended. With every radiator installed you will also need a pair of valves to sit at either end to control the heat output. The valves will need to be the right size (usually either 15 or 22mm) and fit the pipes that you have installed. Radiator Styles There are many radiator styles to choose from with colours and designs to suit any interior. Below are some of the most common radiator styles on the market:

  • Central heating radiators. You can find this style of radiator in many homes as they offer the biggest heat output and best efficiency rate. This style of radiator uses large panels (also known as convectors) to heat the room. Central heating radiators are available in smaller panels to heat small rooms, standard sizes, and double or triple panels for large rooms.
  • Column radiators. This style of radiator offers a more traditional aesthetic, similar to the Victorian cast iron radiators. However, unlike their Victoria predecessor, they distribute heat far more efficiently.
  • Vertical radiators. Vertical radiators are another option to consider when searching for the right radiator style. Vertical radiators are ideal for tall walls without the space to fit a traditional horizontal style radiator. Available in a range of styles and colours, vertical radiators can even be a design feature in and of themselves.
  • Towel radiators. A towel radiator is a perfect addition to a bathroom, keeping your towels warm and dry whilst also heating the room. Available in a variety of heights and widths, there is a towel radiator to suit every bathroom design.

Radiator Materials Radiators are available in different materials, each with different properties and price points. The material of the radiator will affect how quickly it heats up and cools down, and the material you select will depend upon your budget.

  • Cast Iron: Cast iron radiators take longer to heat up and they also cool down slower than other materials, which means they will keep a room warm long after the heating has been turned off. They are often hailed as a great choice for rooms with tall ceilings and provide an option for authentic period décor.
  • Stainless Steel Radiators: This radiator style is very efficient and because it is made of stainless steel it will not rust or corrode as some other metal radiators do. However, stainless steel radiators are often priced higher than other materials so you will need to consider your budget.
  • Mild Steel: Mild steel is a common choice for radiators at a lower cost than stainless steel. Mild steel radiators are available in a variety of styles and colours.
  • Aluminium: Aluminium is an ideal metal for radiators as it is fast to heat up and just as quick to cool down. Aluminium radiators are also lightweight and very easy to install making them a popular choice amongst modern homes.

Once you’ve chosen the style and material of your radiators you will need to think about how you will install them. You have two options, installing them yourself or asking a plumbing professional, such as Perfect Plumbers, to help you. Painting a Radiator In some cases, you may want to repaint a radiator, so if this is the route you choose here are some tips to keep in mind.

  • Always apply a coat of primer first, referring to the manufacturer’s instructions as you go.
  • Use radiator paint to decorate your radiators because it has been specifically created to resist high temperatures on metal surfaces without discolouring.
  • Once the primer is dry, paint over starting at the top and using vertical brush strokes.
  • Before painting a radiator make sure it is cold first.
  • After you have finished painting, be sure to turn the radiator back on within 24 hours so that the paint can ‘cure’ properly.
  • Be careful not to paint over any valves or fittings as this could make it hard to operate them.

DIY Safety Tips

Before undertaking any DIY work you must always make sure you follow the correct safety advice to protect yourself and others. We have listed some of our top DIY safety tips below, but please remember if you are ever unsure of any aspect to call a qualified professional for advice.

  • Wearing the right safety equipment for the task is one of the first things to remember. Protect yourself with gloves, safety goggles and a dust mask if you are working with hazardous materials.
  • Avoid wearing loose-fitting clothes or jewellery that can easily get caught.
  • When working with any hazardous materials you must also make sure the room that you are working in is well ventilated by keeping doors and windows open.
  • Use the right tools for the job and make sure the tools are in good condition. If you need to make any repairs or changes to the tools, make sure to turn them off and unplug them before you change any parts.
  • Always keep tools away from pets and children, both while you are working with them and when you are storing them in between use.
  • If you are using a knife, always cut away from yourself and make sure the blade is sharp enough. A dull blade is more dangerous than a sharp blade.
  • When working on or near an electrical system make sure that the power is switched off first and you have removed fuse or circuit breaker.
  • If you are working on or near an electrical system, wear rubber-soled boots to prevent electricity earthing through you in an accident.
  • When using an A-frame ladder, make sure it is fully locked in the open position before using it.
  • If you are using a leaning ladder, leave four feet at the base for every one foot of height.
  • Give yourself enough time to complete the DIY task at hand without needing to rush.
  • Always keep a well-stocked first aid to hand and have somebody on standby that you can call in the event of an emergency.
  • When working on plumbing systems always make sure you have turned off the water supply using the stopcock, or make sure that you have isolated the appliance you are working on.

What Tools Will You Need?

When removing and installing radiators you will need the following tools in your kit:

  • A radiator bleed key
  • A spirit level
  • A pipe cutter
  • An adjustable pipe wrench
  • An adjustable spanner
  • A tape measure
  • A bucket
  • A dust sheet
  • Pipe tape
  • A screwdriver

These tools will make it incredibly easy for you to get the job done. Using the wrong tools could be risky as this could damage parts of the radiator, which can have much worse problems down the line.

Removing an Existing Radiator

If you are replacing an existing radiator you will first need to remove the old radiator to make room for the new one. Turn Off The Water Supply The first step is to turn off your central heating and make sure that the system has completely cooled. Then you will need to turn your attention to the valves at the bottom of the radiator. Locate the manual control valve that turns the radiator on and off and turn it to the off position by rotating it clockwise. If you have a thermostatic valve double check to make sure that it is turned off fully and not just set to the ‘frost setting’. The valve at the other end of the radiator is known as the lockshield valve as this controls the flow of water through the system. Take the protective cap off the lockshield valve and turn the top square piece clockwise as far as possible using your adjustable wrench. While you are doing this, keep track of how many turns it takes to close it as the valve will need to be opened by the same amount once you have installed your new radiator. Drain the Radiator The next step is to drain all of the water from the radiator using the manual control valve. Place a bucket underneath the valve and then grip the body of the valve with an adjustable wrench. Holding it steady, take another wrench and gently loosen the nut that connects this valve to the radiator. To allow the radiator to start to drain out you will need to break the vacuum inside and allow any trapped air to escape first. Taking a radiator key, carefully open the bleed valve at the top of the radiator to release the air. You should notice a hissing sound as the air escapes. Once the air has been released the water will then start to flow out of the manual control valve at the bottom. Keep draining the water until the flow stops. Removing the Radiator Once the radiator has been drained of all water you can then remove it from the wall. Start by undoing the nut that holds the lockshield valve to the adapter within the radiator. A bit of force might be required to free the connections from the central heating valves and pipes, but take extra care not to bend them. Once the radiator is freed from its connections you can then carefully lift it upwards to remove it from the brackets. You may need a helping hand for this as radiators are quite heavy, so do be careful. Close the radiator’s bleed valve with the radiator key and tilt the radiator to one side, catching any remaining water in a bucket.

Installing a Radiator

Once you have removed your old radiator, you might want to take the opportunity to decorate behind the radiator with paint or wallpaper. You can unscrew the brackets from the walls to get the perfect finish, just remember to keep track of where the screw holes are to replace the brackets afterwards. When fitting a new radiator, always refer to the manufacturer’s instructions. Hanging a New Radiator If you are hanging a radiator that is the same size as your old radiator the steps are straightforward. However, if your new radiator is smaller than the original contact your plumber first for advice. The first step is to fit the control and lockshield valves before you install the radiator and make sure they are open. Once this is done, lift the radiator onto the wall brackets and tighten the nuts that connect the valves to the radiator at both ends. This can be somewhat tricky so you may need somebody to help you hold the radiator in place while you do this. Also, be careful not to overtighten the fittings – tighten them mostly by hand, just enough so that they are watertight. Once the radiator is in place, open the thermostatic or manual control valve and open the bleed valve found at the top to start filling it with water. Once the water stops making a gurgling sound, open the lockshield valve using the same amount of turns that it took to close it when you removed the original radiator. Finally, check all the joints to make sure there are no leaks and then turn on your central heating system. While the heating is on, double-check the radiator for any leaks.

Hiring a Plumber to Install Your Radiators

If installing the radiators yourself is not a task that you want to tackle, you can ask a professional such as Perfect Plumbers to help you. Finding the right tradesperson is important and to make your search easier we have included some useful advice below. Qualifications and Accreditations When searching for a plumber, the most important thing to look at are their qualifications and accreditations. You will need to establish what the job entails first and then search for somebody with the right experience. If the job involves working on your central heating system you will need to find a Gas Safe Registered engineer. The Gas Safe Register is the UK’s official register of engineer’s that are qualified to legally and safely work on heating systems. It is also worth checking to see whether your chosen plumber or heating engineer is part of a trade body or association. Trade bodies such as The Chartered Institute of Plumbing and Heating Engineering (CIPHE) The Contractors Health and Safety Assessment Scheme (CHAS) and Which? (as well as other organisations) demonstrate the plumber’s competency and professionalism. It also helps to rule out rogue traders and provides you with peace of mind in the event of any disagreements. Customer Reviews The best way to get a true picture of the service that your plumber or heating engineer provides is by checking out previous reviews from other customers. Check for reviews from customers that have had similar work completed by the plumber for a good indication of the quality of service. Are They a Local or National Company? With many local plumbing companies available and larger national companies, choosing the right fit for you is important. A smaller local company may be more flexible on timescale and prices, and many customers report a more personal and friendly feel to them. National companies will usually have a good reputation and cover a larger variety of works. However, the waiting times might be longer for a plumber from a national company and there will be less room for negotiation on prices. Check Their Website A website will give you a good idea of how the company operates, for example, does it look professional and well updated? Pay attention to the content on the website too to get an idea of the plumber’s experience and areas of expertise. Also, if they have a blog with useful tips and information, this shows that they are willing to help their customers. If a tradesperson or company does not have a website it will be harder to find information on them such as customer reviews, experience, and their qualifications. Do They Have a Clear Pricing Structure? Before you agree to work with a plumber or plumbing company, make sure you get a detailed quote with all works and prices listed first. As part of the quoting process, the plumber should assess the job and your requirements. Then, they should explain how they will complete the job keeping to the requirements, along with the goods and services they will supply. Most importantly, the quote should detail all of the costs involved along with how and when the plumber expects to be paid. For further assurance, you can also ask for a contract containing all the information outlined above and including the plumber’s terms and conditions. Calling a Plumber in an Emergency In the event of an emergency, you may need a plumber to come to your property immediately or even out of hours. If this is the case expect to pay a minimum call-out fee, and perhaps even travel or parking charges on top of the cost of the job. However, even during an emergency call out, the plumber should always be up-front about all the costs involved and any of their terms and conditions that apply. Extra Information Extra things to look out for when choosing a plumber include:

  • Checking how long they have been in business.
  • Asking if the work is guaranteed for some time or covered by insurance.
  • Checking that the company has the right level of business insurance and whether that insurance would protect the work done in your home.
  • Establishing whether there are any additional costs such as parking and travel, or waste removal.