Why Is Right Gas Boiler Sizing So Important?

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Are you considering buying a new boiler for your home heating needs? Then you should know what boiler size you should buy. How to find that out? Gas boiler sizing is always of great importance. Most heating units come in different sizes, thus enabling to choose the right one. In any case, there is one thing that remains clear: a large house needs a bigger appliance than a smaller one.

gas boiler sizing

What Does Boiler Sizing Depend On?

The selection and sizing of a gas boiler depends on three main factors. These are:

  1. Possible installation location of the heating unit.
  2. Correct heat load calculation.
  3. The type of the fuel used.


All three factors are pretty helpful in narrowing down the boiler model and make, which is correct for one’s individual application.

In addition to these three factors, there are also household ones that have a very great influence as well:

  • the house type plays one of the most important parts (detached, semi-attached or attached)
  • the house size takes the second place (square footage)
  • external wall area
  • windows (number and size)

And, finally, don’t forget about the consumption of energy, while working of gas boiler sizing. In case there are more than two occupants or there are some other things that heighten your needs, the boiler size will be affected.

Square Footage

Before buying a gas unit for home heating needs, measure the square footage of your place. While building or purchasing a house, one is likely to be informed of its sizes. In case you weren’t informed, you must measure each room with a special measuring tape, starting from its corner and measuring the two walls, which meet at the spot. Make sure you record the dimensions on a piece of paper.

The boiler size is measured in kilowatts, and not its physical dimensions. Make sure you select the heating appliance on the output required to meet the demands of your house. The requirements can be approximately spaced calculating the home’s square footage. Measure exterior walls and windows to find out possible heat loss. In addition to this, you can add the recommended heat output for each radiator.

Correct Gas Boiler Sizing and Its Benefits

If you pick a gas boiler, which size is appropriate for your home, you contribute to the energy saving program. Pay special attention o high efficiency models with the AFUE certificate, as they manage to reduce all energy and heating costs at to 30%.

If you install a model, which AFUE rating is 90% or even higher, you can decrease carbon dioxide emissions by nearly 2.5 tons. Make sure you don’t install a boiler that is too small or too large, as this is going to derail all efficiency plans you have and cancel all energy savings.

If you are really afraid that your measurings and gas boiler sizing could be wrong, you should better get advice from industry’s experts. Look for the trusted companies and get several advice. Check what they recommend and make your final choice. Keep in mind that boiler size means a lot. Make sure you pick the right one.