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Storage Combi Boiler Replacement Guide


The heating world is always evolving to adapt to the ever-changing needs of the consumers. The storage combi boiler is engineered for homes that don’t have enough space to store the bulky tanks that come with system boilers but require more hot water than a standalone combi can offer.

If you haven’t found a solution to your heating problem, a storage combi boiler could be the answer you have been looking for. As with every other boiler, you need to do some due diligence and research to identify the best boiler output, among other critical factors.

Luckily, you can save time and effort by quickly going through this short guide, for all you need to know about storage combi boilers.

What is a Storage Boiler?

A storage combi boiler is a mix of combi and system boiler. It merges the best of both worlds to serve homes who find combi boilers shorthanded and system boilers to aggressive with regards to space.

With a storage combi boiler, you have a hot water cylinder within the heating unit. This guarantees a supply of hot water to the various taps, showers and baths around the house without affecting the flow rate.

For small homes that don’t need a lot of hot water, combi boilers are a great idea. However, because the boiler has no storage, it can affect the flow rate of water around the house, especially when you run more than one hot water tap.

Often, a system boiler helps to alleviate the problem. But, the sizeable tank takes up more space than most homeowners would want to give up. With a storage combi boiler, you have a middle ground that allows you to enjoy steady water flow without giving up as much space in your home.

How Does a Storage Combi Boiler Work?

The storage combi boiler borrows heavily from the conventional combi boiler in its functioning. The boiler draws water from the mains water supply in your home. The water is taken through the heating elements and once it’s heated appropriately, the water is pumped into the storage tank ready for use.

The tank is heated by the boiler to keep the water hot. You can enjoy hot water on demand and you don’t have to worry about running out of hot water, or low pressure which is a common problem when you use a conventional boiler in a home with high demand for hot water.

Advantages of Storage Combi Boilers

If the storage combi boiler will get the job done for you, understanding the benefits and downsides of having a storage combi boiler will further enlighten you on what to expect.

The pros of having a storage combi boiler include:

A hot water cylinder within the unit

With a storage boiler, you don’t have to worry about the hot water cylinder taking up more space than is necessary. The storage tank of the boiler is installed inside the heating unit, allowing you to enjoy the extra capacity with minimal space footprint.

More hot water

If you tend to use a lot of hot water in your home, a combi boiler might be shorthanded, a storage combi boiler will allow you to access hot water more steadily and it doesn’t affect the flow rate of water when you run multiple taps.

It is cheaper

Without a storage combi boiler, the other alternative would be a system boiler which will cost more as it comes with the bigger storage tank hence driving up the price. It also makes installation easier and cheaper compared to if the boiler was external.

It is solar thermal compatible

Conventional combi boilers don’t give you the option of using solar power to heat water. With a storage combi boiler, you can keep the water hot once it’s in the storage tank using solar thermal. You save more on your energy bills without giving up any comfort.

Disadvantages of Storage Combi Boilers

There’s no doubt the storage combi boiler is awash with beneficial features. However, there are some downsides, as well. Knowing which ones they are can help you make a more informed decision.  

It’s larger than a combi boiler

The addition of a storage tank means the storage combi boiler is larger than a typical combi boiler. The difference in size will depend on the size of the hot water cylinder you want. But, most of them can be wall-mounted.

Hot water access is limited

Having a storage tank doesn’t mean you are completely liberated from the inconvenience of irregular hot water. The convenience of having hot water is dependent on the size of the tank.  To avoid running out, you should take note of the size of the cylinder and how long it takes to fill up.

It costs more than a combi boiler

Expect to pay a little more to enjoy the convenience of the storage tank. Typically, storage combi boilers cost more than combi boilers.

How Much Does a Storage Combi Boiler Cost?

The cost of having a storage combi boiler can make or break your plans to install the new boiler. Luckily, storage combi boilers are not expensive. A decent storage combi boiler will cost you about £1,500. However, this price will differ depending on the model and the technical features of the boiler. The size of the storage tank of the boiler you choose will also impact the price.

Don’t forget about the installation cost. The installation cost of any boiler is significant. If you’re putting together a budget, having an accurate installation cost will go along way in avoiding any sudden expenses that could affect your finances.

If you’re having problems getting an accurate quote for your storage combi boiler installation, we can get up to 4 installers in your area to call you and provide you with a FREE, no-obligation quote.

What are the Running Costs of a Storage Combi Boiler?

Running a storage combi boiler is slightly more expensive to run than a combi boiler. The extra cost is because the boiler has to keep the water in the tank hot. However, you can mitigate the costs by using solar thermal to keep the water in the tank hot.

Other than the difference in energy consumption, most of the additional long term costs associated with running a storage combi boiler are more or less the same as those of running a combi boiler. Some of the costs include servicing and maintenance.

What is the Best Storage Combi Boiler?

There are plenty of storage combi boilers to choose from. Selecting the best might be an uphill battle and one that you might find quite challenging. If you need a little direction to help you make the right pick, here are three of the best storage combi boilers that are also strong candidates for any home.

Glow Worm Energy 35 Store Combi Boiler

The Energy 35 Store boiler is a great option for homes that want a balance between portability and a constant supply of hot water. This wall-mounted tank comes with two 21 litre storage tanks and has a flow rate of up to 19.7 litres per minute. It’s the ultimate workhorse and it doesn’t take up all the space in your home.

The 5-minute reheat time frame, 7-year warranty and LPG compatibility open this one of a kind storage combi boiler to a world of opportunities and make it an ideal addition to plenty of homes.

Vaillant ecoTEC Plus Combination Storage Boiler

The Vaillant ecoTEC is a highly efficient 38kW boiler capable of producing up to 20 litres of hot water per minute. Once the storage tank is full, the boiler modulates the temperature of the water using only 16% of the power.

If you’re keen on saving money on your energy bills, this option is perfect. It has an ErP grade A rating. It’s compact and has integrated hot water storage at the back of the boiler with plenty of options and features to select from.

Viessmann 11-W Storage Combi Boiler

This is a great high output boiler that will work for large homes that need a constant supply of hot water. It’s also perfect for tech-savvy homeowners who don’t mind having a few more features that make it more convenient to use the new boiler.

The boiler puts out 18 litres of hot water per minute with an output 35kW, a central loading system, an integrated 150L stainless steel storage tank, a Grade-A efficiency rating, and you can also opt to have a wireless remote control with your boiler for convenience.

Get Free Quotes for a Replacement Today!

Compare the Boiler Market can help you make the process of getting a new storage combi boiler installed easier and smoother. We can help you get competitive boiler replacement quotes for your new boiler.

We will have three installers from your area call you and provide you with a FREE no-obligation quote. To give you an accurate quote, the installer will ask you about the type of boiler you want to install, the extent of pipework required and if there are any repairs needed.

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