System Boilers

How long should a System Boiler Last?

Most boilers, regardless of their type, should last between 10 to 15 years on average.

If you have an older boiler approaching the end of its life, you may want to consider purchasing a new one. The older boilers, especially those installed over 10 years ago, are considerably less efficient than modern ones.

Are System Boilers more reliable?

Despite the fact that system boilers can sometimes be more expensive than other types of boilers, such as combi, they are more reliable.

System boilers can handle high hot water demand with ease, meaning multiple members of the household can use hot water at the same time. This is because a cylinder is installed.

They also use the mains water supply when delivering water to your hot water outlets which provides improved water pressure.

What to consider when comparing System Boilers

When comparing system boilers, there are a few things that you will want to be aware of.

• Output:

One of the most important factors is output, as you will want to ensure it sufficiently meets your home’s water needs and requirements. System boilers have central heating output ratings which gives a reflection of how many radiators the unit is capable of heating up.

• Efficiency:

Another factor is efficiency. Boilers work by converting fuel into usable energy, and how much fuel that gets converted is reflected in the efficiency ratings. The higher the efficiency rating, the less energy is wasted when in use.

• Budget:

System boilers can cost around £500 – £2,000 without the cylinder and before installation. Depending on how much you’re willing to spend, there are many options to suit varied budgets.

• Reviews:

Finally, you may want to look at reviews from heating engineer specialists. Reviews and opinions from fully-qualified experts will give you valuable insights into the system boilers you may be considering.

What hot water cylinders do you need?

Knowing which hot water system you need is not the easiest thing to understand, and you may not even be sure about what you’re looking for.

In simple terms, the hot water cylinder you need for your home depends on how you intend to heat your water and how you want the hot water to be distributed.

Direct vs Indirect Cylinders

With direct cylinders, the water is heated directly by the cylinder itself through an immersion heater. Some cylinders have more than one immersion heater installed inside them to allow for a more powerful performance, therefore producing hot water quickly. Direct cylinders come as either vented or unvented models. This impacts how the water is distributed across the property to the hot water outlets and they tend to be used when a traditional central heating system is not available.

Indirect cylinders rely on external appliances to apply the necessary heat to the cylinder. This generates the hot water that is stored, and also used as a backup if the main heat source fails. The water is indirectly heated by other appliances, like a boiler, but it may also include things like solar panels. An internal heat exchanger in the cylinder transfers heat from the external appliance to the water cylinder.

Some indirect cylinders contain immersion heaters that allow the cylinder to add additional heat to the stored hot water. Indirect cylinders are therefore able to generate hot water much more quickly than direct cylinders.

Unvented vs Vented Cylinders

If you need a cylinder which uses the mains water pressure to distribute the hot water around your home for use at your taps and showers, you will need to invest in an unvented cylinder. Unvented cylinders are commonly used as part of a system boiler installation. This enables you to take advantage of the high pressure water supply. Unvented cylinders also take up less space than vented cylinders as no feeder tank is required.

Vented hot water cylinders rely on a feeder tank to provide it with cold water from the mains. This water is then heated and distributed to the hot water outlets as part of a gravity fed system. Vented cylinders are usually used alongside regular boiler installations, whereas unvented cylinders are used with system boiler installations.

What are the pros and cons of a System Boiler?

Just like with any boiler, system boilers come with their pros and cons so it’s best to consider these and do your own research before committing to one.

Pros of a System Boiler

1. They can handle high hot water demand. The large amount of hot water stored in the tank allows numerous household members to use hot water at the same time without affecting the pressure.
2. Eco friendly. The insulated water cylinders are an economical way to provide hot water to a number of outlets. Not to mention water storage cylinders and tanks of system boilers can be heated through solar panels after installation.
3. Improved water pressure. System boilers use the mains water supply when delivering water to your hot water outlets, which provides improved water pressure.
4. Extra loft space. System boilers only require a small amount of space for water cylinders, unlike regular boilers which require large plastic feeder tanks  to be installed in your attic.

Cons of a System Boiler

1. Lack of instant hot water. System boilers have a large amount of water to heat up, and this happens relatively slowly. This means if your boiler has been switched off for a significant amount of time, you will be waiting for the water to be heated up from cold, which may take a while.
2. Take up more space than combi boilers. System boilers require an additional water cylinder that takes up space in your home, unlike a combi boiler which is only the component itself.
3. Price point. Because of the separate components and size, system boilers tend not to be the cheapest on the market.

Common System Boiler problems

Just like with any boiler, system boilers can have their problems. These can include:

• Leaking. A boiler leak is usually caused by an issue with an internal component. If the leak comes from your relief pressure valve, it’s likely that the system’s pressure has become too high.
• Low boiler pressure. You can tell if your boiler’s pressure is too low by looking at the pressure gauge. Low pressure can be caused by system leaks, recently bled radiators or failed components.
• No heating or hot water. This may be concerning with system boilers as the tank is supposed to store hot water. Your boiler may need repressuring or the thermostat adjusted. If you cannot safely find a solution, it’s best to consult a professional.
• Boiler breakdown. If the above issues are left unaddressed, the above issues can lead to a complete boiler breakdown. If this is the case, you should contact a gas safe registered engineer as soon as possible.

Hot water only works when System Boiler central heating is on or the immersion heater is turned on?

If hot water only comes out of your taps when the central heating is on, it is likely that the diverter valve isn’t diverting hot water properly. If you think this is the case, we would recommend calling our Gas Safe registered engineers to take a look at it for you. The work carried out on gas appliances can be dangerous and can damage the boiler if it isn’t handled professionally.

Our boiler engineers will be able to run checks to see if a faulty diverter valve has caused the issue, or if there is potentially a different underlying issue. Lacey Plumbing and Heating will be able to offer you a high standard of care and expertise for any boiler repair issues.