Wet Central Heating System: How Does It Work?

water radiator boiler

Are you looking for the right central heating system to get for your property? Are you considering getting an upgrade or are you just plain curious? No matter what your agenda is, in this article, we’ll try to help you understand how central heating systems work.

There are currently three main kinds of central heating systems, but first, we’ll focus on understanding how the wet system works.

How does a wet central heating system work?

Your property should have a central heat source first. It can either be a standard or a combination boiler. This central heat source is in charge of producing hot water that is distributed around your property, usually through radiators. 

What is the difference between a standard boiler and a combination boiler?

A property that uses as a standard boiler has a water cylinder used for storing hot water. A combination boiler, on the other hand, can provide instant hot water through a more compact unit. It is the more popular boiler type and is considered more efficient.

How does the boiler work?

Boilers need fuel to work. There are different power sources for your water boiler. Understand how each works and see the advantages and disadvantages when it comes to their performances.

1. Oil-fired boilers

Oil is used as the fuel for oil-fired boilers. The oil is ignited in a combustion chamber and the heat exchanger then warms up the cold water in the cold water tank for those who use a standard boiler and in the mains for the combination boiler users. This heated water then travels through radiators for the tap and shower usage.

It is often the boiler type that families use when they can’t connect to the gas grid or when they prefer a cheaper alternative. Gasoline or petroleum-based oils are not the cleanest energy source, and its price may fluctuate often, but it is an efficient way to heat water. Replacing your boiler is also easier when using an oil-fired boiler.

In this process, the oil is often delivered to the property through a truck, and you need to have a separate oil storage tank for it. You have to remember though that an oil storage tank needs to undergo annual servicing. 

2. Gas-powered boilers

The most common type of central heating is gas central heating. In this system, natural gas travels to the boiler through the gas distribution network. The boiler then burns the fuel, and it heats the water that travels through to your shower and tap.  

A gas-fired boiler is as efficient and low-cost as the oil-fired boiler, however, only houses connected to the gas grid can accommodate this type of heating. Similar to oil as well, gas is not the cleanest source of energy, and its price continues to rise. Using a gas-fired boiler, nonetheless, will make boiler upgrades simpler for your home, and there’s no need to store gas in tanks.

3. LPG-powered boilers

Using liquid petroleum gas (LPG) is another alternative for using gas. Similar to the oil-fired and gas-powered boilers, LPG is not the cleanest source of energy. It also tends to be more expensive than the two. 

The process of heating is the same for oil-fired and gas-fired boilers. The LPG-fired boiler heats your water and through radiators, it provides hot water to your taps at home. It also needs to be serviced yearly to maintain its efficiency. When using LPG, you need storage on-site and you 

4. Solid fuel

If your house uses a solid fuel heating system, it uses coal or wood chips to ignite heat. It is the traditional way of heating water and is rarely used nowadays. Though the biomass used in the burning process is considered as sustainable materials, its emissions aren’t always environmentally friendly. Using this heating system will also require daily cleaning for proper maintenance.


The wet central heating system is considered the most efficient and cost-effective way of providing heated water in properties. You just have to find which type works best for your current setup and observe proper maintenance for it to work properly throughout the year.

Got more questions about boiler services or central heating systems? We’re Grampian Boiler Services, proudly serving the Grampian area – call us today at 07470697629!

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