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The Ultimate Guide To The Best Thermostatic Radiator Valves

best thermostatic radiator valves
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We are all aware of the significance of increasing our energy efficiency and energy conservation. This reduces carbon emissions while also allowing us to maintain reasonable energy costs.

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By keeping a room at the right temperature, thermostatic radiator valves are a simple way to take control of your home heating. These energy-saving TRVs may be something to take into account if you’re getting a new boiler quote.

This guide will teach you everything you need to know about thermostatic valves and offer suggestions for some of the best products on the market right now.

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What is a thermostatic radiator valve?

You can regulate the temperature in each room of the house by installing a TRV on each radiator. Therefore, it is much simpler to decrease energy use, which will lower your energy costs.

One of those things that, once you have it, will make you wonder how you ever got along without it is thermostatic control.

Choosing the right thermostatic radiator valve will also depend on the size of the radiators in your home.

Do TRVs measure the temperature in a room?

Yes. Thermostatic radiator valves operate by determining the room’s temperature and then modifying the heat output to maintain the desired temperature range. This implies that you can control the home heating separately for each room.

While the valves can be used with a variety of boiler types, it is advisable to confirm compatibility before purchasing.

As many people prefer a bedroom to have a lower temperature than a living room, thermostatic radiator valves provide you with the control to get the perfect temperature in every room

The TRV can also be used for temperature control of a towel rail.

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How do thermostatic radiator valves work?

The TRV functions as a self-regulating valve by modifying the rate at which hot water enters the radiator.

The thermostatic radiator valve head is located at the top of the valve. The valve head expands as the room’s temperature changes. This causes the pin inside the valve body to adjust, opening or closing the valve. This implies:

TRV’s regulate water in the radiator

The thermostatic radiator valve head closes as a result of the room’s expansion as it heats up, allowing less hot water to reach the radiator.

Contraction occurs as the room cools, which causes the valve body to open. More hot water then starts to flow into the radiator as a result of that.

Different designs of thermostatic valves

The wax and liquid models were the two initial designs for thermostatic valves. The most recent invention is a liquid thermostatic radiator valve, which has many advantages over wax models, including the ability to respond to temperature changes much faster.

The speed of adjustment varies, but both thermostatic valve designs are capable of providing automatic adjustments.

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Electronic thermostatic valves

Older models simply can’t compete with the level of dependability and setup simplicity offered by electronic thermostatic radiator valves. The ease with which you can control your radiators and home heating system is what has caused their popularity to grow significantly.

Control your radiator valves with your phone

The heat output of your boiler can now be easily adjusted using the screen on your phone.

There has been some pushback on the honesty of some manufacturers’ huge claims about the amount of money you will save with smart home technology. It will take a long time to recover your investment if you are tempted to buy one of the full smart heating systems.

Smart radiator valve vs a smart heating system

Lower investment

A smart radiator valve is significantly less expensive. You can still install several smart valves, each of which allows you to control the radiators in each room.

Option for voice control

Many smart TRVs are Alexa or Google Assistant compatible, giving you greater control over the heat provided by your radiators.

Ideal for rented accommodations

When renting a home, the last thing you want to do is pay for an entire smart system. Buying one or two TRVs that you can take with you when you move is a much better option.

Get a new boiler on finance and your smart thermostat will be included in the price.

TRV fitment shapes vary.

TRVs come in a variety of shapes to accommodate different types of installations; corner, angled, and straight valves are three of the most common.

Angled valves

The most common type in the UK is the angled valve, which connects a radiator to the central heating system at an angle of around 90 degrees.

Corner valves

When the central heating pipes emerge from the wall, a corner valve is installed. Angled valves could be used, but they would require the valve to be turned 90 degrees, which would cause it to protrude from the radiator.

The valve on a corner TRV faces inwards. These valves are also known as flat front valves.

Straight radiator valve

When the radiator pipes run straight along the wall and into the radiator valve, straight valves are typically used. This type of valve is typically connected horizontally across the floor.

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What are manual radiator valves?

The most common type of radiator valve used in heating systems is the manual valve, which functions similarly to a tap. Simply turn it on, and the central heating water will flow into the radiator. You can turn off the radiator once it has reached the desired temperature.

While manual valves are convenient, it is critical to remember to turn them off once they have reached the desired temperature. If you do not, you will notice that your heating bill will begin to rise.

There are a variety of manual valve designs available in both traditional and contemporary styles.

What are lockshield valves?

The lockshield valve is a macro-level valve that controls the heating system, whereas the temperature valve is a micro-level valve.

The lockshield valve’s primary function is to balance that specific radiator and ensure that the entire system is in sync. As a result, all of the radiators will heat at the same rate.

It is critical to ensure that the heating system is balanced before adjusting the radiators to heat individual rooms. The valve can also be adjusted to alter how long it takes for a radiator to heat up.

Making changes to the lockshield valve

If your radiators aren’t heating up evenly, adjusting this valve is a good place to start. It’s important to note that this isn’t something that should be done on a regular basis; once the heating system is in sync, it shouldn’t need to be adjusted again for a while.

If you’re not sure which valve is the lockshield valve, look for one that has a plastic cup covering it. This is done to demonstrate that it should not be adjusted on a regular basis or simply because you need to adjust the heat given off by a radiator.

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Thermostatic radiator valve positioning

TRV valves are a great way to control the temperature in different rooms of the house. However, if they are not used correctly, you will not benefit from them.

While a heating engineer can assist you with thermostatic radiator valve installation, it does not have to be a Gas Safe engineer.

It’s worth noting that when installing the new thermostatic radiator valve, the new TRV may not appear to fit on the current valve insert. TRVs come with a new insert, so simply remove the old one, slip the new one in, and loosen the part with an adjustable spanner.

Don’t fit a TRV in a room with a wall thermostat

If a room already has a thermostat, you don’t need a thermostatic radiator valve. This is due to the fact that the two thermostats will compete to raise or lower the temperature in the room.

Don’t fit a TRV in a bathroom

TRVs are also not a wise choice for bathrooms. This is because taking a bath or shower can cause the TRV to shut down. This is common even when the TRV is set to the highest temperature.

Installing a TRV on a towel rail

Most homeowners believe that TRVs are only useful for controlling the temperature of their radiators. However, they can also be very useful for providing great control over towel rails, but there are some things to consider before having one installed.

It is entirely possible to install a thermostatic radiator valve on a heated towel rail in the same way that radiators are. However, it is usually preferable to have at least one radiator with a manual valve rather than a TRV. Towel rails are commonly used for this purpose.

The reason for this recommendation comes down to safety. If there was a failure of the TRVs in the home and as a result, they didn’t open then it would still be possible for the heated water to flow through the radiator that doesn’t have a TRV fitted. This then prevents any damage to the boiler or pump.

Another reason why TRVs are not normally installed in the bathroom is that the heat from the shower or bath can make it difficult for them to work accurately. That then means they cool down the radiator because of the heat of the steam. Then when you step out, you’re met with a cold bathroom.

However, you can still do this, but you must be aware of the risks involved.

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What size radiator valve is required?

When we talk about the size of radiator valves, we’re talking about the size of the pipework. The standard radiator pipe size in the United Kingdom is 15mm. However, if you purchase a thermostatic valve from another country, you may find sizes ranging from 8mm to 28mm.

That doesn’t mean you can’t use them on your heating system, but you’ll need adaptors or connectors to make them fit UK standard pipes.

Radiator valve position

Most thermostatic radiator valves are typically installed at the bottom of standard radiators, though there is no rule requiring this. However, if you do install the valve at the top, it must be bidirectional. This is due to the fact that the connection at the top of most radiators is usually the return pipe rather than the inlet pipe.

Another factor to consider is that the air temperature at the top of a radiator is higher than at the bottom. That may imply that if you’re heating rooms with radiator valves installed at the top, you’ll need to set the valve to a higher temperature than usual.

Replacing a thermostatic radiator valve head

If the TRV head fails, it is not expensive to replace. That’s because there is no need to replace the whole valve, you can just get a replacement head.

Check for compatibility before purchasing a replacement head, as there are numerous options and fitments.

When shopping for a new radiator valve head, look for ones that have a frost protection setting. This ensures that even if temperatures drop outside, your home will remain warm.

Look for a TRV head that not only protects against frost but also has a temperature limitation feature. This means that the temperature cannot rise above 28 degrees Celsius and cannot fall below 8 degrees Celsius.

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Our top thermostatic radiator valve recommendations

Now that you’ve learned everything there is to know about thermostatic radiator valves, let’s take a look at our top five recommendations.

Kartell TRV thermostatic valve

This is one of the most well-known and widely used thermostatic valves. It offers a simple and affordable solution, but don’t confuse affordable with low quality; this is a good-quality TRV. If you’re looking for a valve that can be attached to a towel rail, this one should be on your list.

This radiator valve has a modern design that will complement any home. We like how they can be fitted both vertically and horizontally, allowing for flow through the body in both directions.

Key features

  • steel valve fitted with a plastic cap
  • fits a 15mm pipe
  • comes with a one year guarantee

HB Signature thermostatic radiator valve

If you want to give your radiator valves a more modern look, the HB Signature TRV’s combination of a brass valve and an anthracite finish could be the perfect solution. The fact that the manufacturers offer a five-year guarantee demonstrates their complete confidence in the quality of their products.

This angled radiator valve is suitable for both radiators and towel rails and fits a 15mm pipe. Another appealing design feature of this model is the easy grip cover, which makes temperature adjustments simple.

Key features

  • solid brass
  • chrome finish which is resistant to both flaking and cracking
  • comes with a five-year guarantee
  • can be fitted to a towel rail

Realm chrome thermostatic radiator valve

This corner thermostatic radiator valve is ideal for replacing a side-fitted radiator valve. This is the most common type of valve required when pipes emerge from the wall.

Although it appears to be a chrome TRV, it is actually made of brass with a chrome finish. This gives your home a sleek and modern appearance.

The Realm thermostatic radiator valve is bi-directional and designed for 15mm pipework. That is, it can be installed on both the flow and return pipes. While this is one of the most expensive radiator valves, it comes with a six-year warranty, so it could save you money in the long run.

Key features

  • solid brass coated in chrome
  • bidirectional valve
  • six-year manufacturer guarantee
  • can be fitted to a towel rail

The iBathUK Radiator Valve Central Heating Tap RA31A

If you’re looking for a manufacturer with a good reputation, iBathUK should be at the top of your list. Few companies are willing to provide a ten-year guarantee on their radiator valves, but iBathUK does!

If you’ve assumed that all of this means that it’ll be expensive, you’ll be pleasantly surprised! The RA31A is one of the least expensive radiator valves, which means it will pay for itself quickly.

This model has a brass core, so there will be no corrosion and it will have a long working life. We like the glossy finish on this radiator valve because it makes it more of a feature in the room rather than something you want to hide away.

This is a 90-degree angled valve that comes with a standard radiator connection of 15mm. One final feature we like is that ibathUK makes their valves with a triple-layer formula, which makes them completely leakproof.

Key features

  • built with a triple layer of brass
  • designed to be highly leak-resistant
  • an amazing 10-year guarantee
  • corrosion-proof

Drayton TRV

The Drayton TRV, an angled thermostat valve, is the last but not least on our list of recommended radiator valves. This radiator valve has been on the market since 1993 and is one of the best-selling in the UK.

This self-contained device allows you to set the desired temperature and then does all of the work for you, ensuring that the room is at the correct temperature.

One of the problems with radiator valves is that they can become stuck. Drayton has avoided this issue by equipping their radiator valves with non-stick internal mechanisms.

It has a chrome and white design and can control radiator temperatures between 10 and 27 degrees. This is another radiator valve with frost protection built in.

Drayton radiator valves are Energy Saving Trust recommended, and the European Valve Manufacturers Association rates them as class one for efficiency. So, if you’re looking for radiator valves with high efficiency, this could be the model to choose.

Key features

  • Self-operating device
  • Frost protection as standard
  • Can bear temperatures up to 110° C
  • 1-year guarantee

Is a thermostatic radiator valve useful?

If you want to cut your energy consumption and utility bills, you should make sure your boiler is running at peak efficiency. If your boiler is more than ten years old, it is unlikely to achieve the level of energy efficiency that is possible with today’s heating systems.

Finding a new boiler quote is the next step in lowering your energy bills and carbon footprint.

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