There are a wide range of central heating systems available, and can be
classified as follows:
Combination or Combi boiler system
Mains pressure or System boiler
Conventional gravity fed or Regular system
COMBI BOILER SYSTEM
The combination boiler central heating system is easily the most popular boiler installation in the UK today.
These systems don’t require a feed tank, expansion tank or a hot water cylinder because they heat water as and when you need it.
This means that they require a lot less space and are also economical – they only heat the water that you need.
A Combi boiler heats water on demand requiring no tanks within the loft space
Electronic controls paired to your boiler
Mains supply fed directly to the combi system
Modern thermostatically controlled radiators sized accordingly
Great for space saving
Perform well with showers
Endless amounts of hot water on demand
Very economical – you only heat what you use
No risk of loft pipework freezing
Less need for pipework so installation in generally cheaper
As with the other systems, combination boiler systems also have their drawbacks. The main one is that their flow rates can be quite low as the water has to be heated as it travels through the boiler i.e. there is no stored hot water to fall back on.
This means they are unsuitable for homes with two or more bathrooms as the simultaneous use of two outlets will decrease the flow rate even further.
Combi boilers have two heat outputs: Hot water for your taps and shower and hot water for your central heating system and radiators.
It takes more effort and therefore more heat to get hot water to your taps and shower than it does to your radiators, so what you must consider when deciding on the right central heating system for your home is the hot water output your household will need.
Use our Comparison Tool to view the full range of combination boilers available and get installation quotes from local, trusted heating engineers.
MAINS PRESSURE HEATING SYSTEMS
These systems supply mains pressure hot water through the taps in your home.
Water is drawn in from the cold water mains and is heated by your boiler
It is then stored in a storage tank (called an unvented cyclinder) until required
When you turn on a tap, cold water from the mains forces the heated water into the central heating system and out through the tap.
The pressure at the tap of a high pressure heating system is the same as the pressure of the mains which in most cases is a lot higher than you would normally experience.
These particular central heating systems are great if you have a high mains pressure to start with but if the mains pressure is low then the system is unsuitable. They can also be costly to install and some authorities require a certificate of annual maintenance to be submitted
You want to be 100% sure that your mains pressure and flow rate is strong enough to power a mains driven central heating system. If you go through the expense and hassle of having this type of heating system installed, but you get a trickle of water coming out of your shower – there is little you can do to rectify it at this point.
REGULAR / CONVENTIONAL BOILERS
These central heating systems use a boiler – either a regular boiler or a system boiler – to heat both the radiators and the hot water. The hot water circulates around the system and is then stored in a hot water cylinder until needed.
The water that travels into the boiler for heating often comes from a feed tank or expansion tank in the loft space of the house and it ensures that the volume of water in the system is always at its optimum level.
In addition to the feed tank, there is normally a larger tank present as well that replenishes the hot water cylinder when water is used around the household.
Water from this tank is drawn down into the system by the force of gravity alone – hence the name of the central heating system. The main drawback to this type of system is that you need loft space for the two tanks and an airing cupboard or similar space for the hot water cylinder.
These gravity based heating systems can work well, especially if you live in a low mains pressure area as the gravity aspect of this system can provide you with some decent water pressure if your mains pressure isn’t up to the job.
However, you will find that heating professionals tend not to recommend this type of central heating system anymore as there are quite a few negatives. For example, the need for two tanks in your loft and a cylinder in your airing cupboard can mean that installation costs will begin to creep up given the need for extra pipework and tanks.
If you do live in an older property that already has this Regular style central heating system, then it can be cheaper just to replace certain elements like the loft tank for example, rather than rip it all out and replace it with something else like a mains pressure system.
We offer all types of central heating installations, repairs and maintenance.
Call today for more information on your new new boiler.