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What is a Megaflo Unvented Boiler System?

The Megaflo Eco SystemReady offers market-leading heat-up, recovery, and heat-loss figures. It also has factory-fitted plumbing, and wiring, and is intended to be installed with a system heating boiler. This not only saves time but also makes the installation look cleaner.

What is a Megaflo Unvented Boiler System?

Megaflo, also known as a Megaflo unvented system or sometimes mispelled as Megaflow system or Megaflow boiler, is a stainless-steel unvented cylinder that stores hot water as part of a central heating unit. It is important to remember that Megaflo is not a boiler but a hot-water cylinder (not to confuse with Baxi’s Megaflo range of boilers).

Megaflo cylinders can be either “indirect” (or “direct”) There are two types of Megaflo tanks: direct or indirect. The difference is how water is heated. If your boiler fails, there will be a switch at your cylinder. This switch will activate the immersion coil in your cylinder to heat the water. Your boiler won’t supply hot water. It is not recommended to turn on your boiler and immersion switch simultaneously.

You’ll be glad to know that most of the Megaflo range can work with the best system boilers that are on sale in the UK.

Who Manufactures Megaflo systems?

Heatrae Sadia manufactures the Megaflo, a specialist in hot water cylinders as well as storage water heaters. Heatrae Sadia’s most acclaimed and highly regarded hot water system, the Megaflo, is an award-winning product. This hot water system is a good fit for modern lifestyles that require more hot water. We need more hot showers, baths and radiators. Hot water is both a luxury and a necessity. Heatrae Sadia is proud of their Megaflo products because they offer a balance between efficiency and reliability.

What is a Megaflo?

Direct Unvented Megaflo

Unvented Megaflo systems use mains water for their water supply. The cylinder’s immersion heater heats water with electricity until it reaches the temperature set by the thermostat. To ensure hot water when you turn on an outlet, it is recommended that the thermostat be set to 60 degrees. The Megaflo system will replace the hot water in the cylinder with cold water from the mains water feed.

Indirect Unvented Megaflo

The indirect Megaflo system uses hot water from an external source, rather than the unvented direct Megaflo. The coil in the cylinder maintains the temperature of hot water, keeping it at the set temperature by the thermostat. The boiler will start to heat the hot water as soon as the hot water leaves the indirect Megaflo.

Megaflo: The Pros and the Cons

The Megaflo is one of the best hot water cylinders available. But as with anything, there are upsides and downsides. If you’re considering investing in Megaflo for your home, let’s look at the pros and cons.

Megaflo: The Pros

The removal of a cold water tank offers multiple benefits to an unvented system.

  • A small household will not need enough space to install a large loft-mounted tank and a cylinder.
  • There is less chance of water getting contaminated if it is stored in a cold water storage container.
  • You don’t require a cold water tank so you have more freedom in where you can install your Megaflo Cylinder.
  • Mains pressure is used to improve performance of baths and showers, particularly for those who like “power showers”. Your system will maintain a constant water pressure, even when more than one outlet are being used simultaneously. This is great news for busy households.
  • Megaflo cylinders can be installed quickly and are simple to maintain and replace.
  • They are 60mm thick.
  • This system can be used to power solar PV if your boiler fails or you have no other options.
  • There are many safety features included with the system. When the boiler reaches the right temperature, the cylinder thermostat will turn it off. The Temperature/Pressure Relief Valve, (TPRV), will shut down the boiler if it gets too hot.

Megaflo: Cons

  • Your system is powered by the mains water supply. There is no backup for cold water. The system will not work without a Megaflo cylinder. It needs to be pushed through the mains water supply in order to deliver hot water.
  • Your mains water supply will be low in pressure. This will cause the water pressure reaching your outlets (showers, taps) to also be low. To determine if a Megaflo is right for you, a hot water flow rate test must be performed.
  • To ensure it can withstand Megaflo’s high pressure, pipework must be double-checked. If the pipework is not suitable for its purpose, it may be necessary to replace it. This can prove costly.
  • High water velocity can cause a lot noise in the pipes.

How can you heat your home with renewable energy?

Heatrae Sadia Megaflo hot-water tanks are compatible with solar thermal energy. This is a great energy source and good for the environment. Solar panels can be a great source of heat backup in the event that your boiler fails.

What guarantee can I expect from a Megaflo product?

High-quality parts and long-lasting warranties are especially important for UK homes with different levels of water “hardness”. There are two types of water in the UK: soft water and hard water. This can cause problems such as limescale buildup in your pipes or kettle. Each Megaflo hot-water cylinder is made of durable stainless steel and comes with a 25 year warranty. The warranties for the other components of an unvented boiler system might be shorter.

Megaflo cylinders can be used with boilers for large homes with multiple outlets and multiple bathrooms. Megaflo cylinders provide hot water in large quantities. This means that you will have hot water at all times. This is a refreshing change from running hot water via the best combi boiler. The boiler splits pressurised hotwater between outlets. This results in a drop of pressure which makes it difficult to have hot water for more than one person.

Safety precautions for an Unvented Megaflo System

Unvented boilers use thermostatic controls to keep the water at a temperature below 100 degrees Celsius. This can be dangerous and could prove fatal.

  • A cylinder should be kept between 60 and 65 degrees Celsius. This is the ideal temperature, and the default setting for controls. This is to reduce the risk of Legionnaires Disease. Anything lower than this temperature can lead to dangerous bacteria growing in the water.
  • The cylinder thermostat will shut off the boiler if the water temperature in the cylinder exceeds 85 degrees Celsius.
  • When water is heated, it expands which raises the pressure in the cylinder. The Temperature/Pressure Release Valve will open if the pressure and temperature are too high. This can cause dangerous explosions and may even lead to death.
  • Gas Safe engineers must install and maintain any boiler, cylinder or other component of your central heating system. To install, maintain and inspect unvented hot water cylinders, the engineer must also have their Unvented Hot Water qualification. A competent person must install and maintain an unvented hot-water cylinder as per section G3 of the Building Regulations Approved document.

The Megaflo unvented Megaflo cylinder from Heatrae Sadia, is a great option for homeowners who are looking for an alternative to their existing system. It also makes it easy to get rid of a cold water tank in their loft. The Megaflo unvented cylinders by Heatrae Sadia are great for homes that have high hot water demands. For your peace of mind, the warranty is good for 25 years. The system pumps hot water efficiently to hot water outlets. You won’t freeze in your shower if you turn on the tap in another area of the house.

Megaflo is the ideal addition to any central heating system if you are looking to replace your vented cylinder with an unvented one but we always suggest you compare so take a look at the latest Telford unvented cylinders that also have much of the Megaflo technology.

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