We all know that when our car gets a bit run down it needs replacing. Unfortunately, most homeowners are not so quick to replace an aging boiler.
Part of the reason for that is, that it can become it a bit of a minefield when it comes to replacing a boiler or simply getting a new one, it can be confusing for the average consumer who is not a heating engineer.
When it comes to choosing a new boiler one of the first decisions you will need to make is whether to go for a combi boiler (combination boiler) or what’s known as a system boiler. A combi boiler is easy and quick to install and does not require a separate water tank. They provide heating for the radiators along with hot water as and when it is needed. A combi boiler is an ideal choice for smaller properties.
For larger homes, a system boiler is recommended if you want to be able to run hot water from multiple taps at the same time.
What Size Boiler Do You Need?
A boiler’s size is measured by its output. The output of a boiler is measured in KW’s or kilowatts. For the most part, the more kw’s, the more powerful your boiler will be. Getting the right size boiler is very important, if you choose a boiler that is too small, you will not have enough heat or hot water in your home. By choosing a boiler that is too big and you will be wasting money on energy that you do not need.
Choosing the correct size boiler will be determined by a number of factors including the number of radiators required, the number of rooms in the home and the number of people. Most household boilers will have an output of 24kw to 42kw.
Very generally speaking a small 1-2-bedroom home would require a 24-27kw boiler, while a larger 4-bedroom house would require 35-42kw. However, it is essential that you speak to a qualified plumber to ensure you get the right advice on the boiler which is right for your home.
One thing that is worth mentioning is that the output of the boiler does not always correlate to the size of boiler and therefore a 43kw boiler will not necessarily be bigger than a 32kw boiler.
Your Old Boiler
Your current boiler size will be able to provide you with some indication of the size of the boiler that you need. However, some things could have changed since your boiler was first installed and you will still require a full survey from a professional plumber. Perhaps you have extended your house since then or your house has become more energy efficient, there are many reasons why you would require a different sized boiler than the original.
Another influencing factor will be water pressure. If you have a regular heating system and you want to go for a combi boiler instead, you will need the right size boiler according to the mains pressure. If you are currently able to run more than one shower at a time without any loss of pressure you might find that if you change over to a combi boiler you might not have adequate water pressure.
There is a simple test you can do to get an idea of the flow rate required. Open one of your taps and see how much cold water you can collect within 1 minute. When choosing a new boiler the boiler will specify how many liters of water it is able to output in a minute and you will then have a good idea if this is equal to or better than your old boiler.
As you can see there are many factors that go into deciding on the correct type of boiler for you and your family’s needs. While a professional installation engineer will be able to give you the best possible advice, it is still a good idea to have some idea of the boiler that will be best for you and getting a professional opinion can also save you money in the long run.