A System Boiler: What Is That and What Is It for?

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In general, a boiler is a vessel in which water or other liquid is heated (and not necessarily boiled). A system boiler is a type of a condensing boiler. Condensing boilers are called so because the vapor produced in the process of their work is condensed into water, thus the waist heat is used to pre-heat cold water. So their efficiency is mostly greater than 90 %, compared to the usual 75-85 % of other boilers. As they are resource-saving and require less fuel, the use of condensing boilers is obligatory or stimulated by financial incentives in many countries.

How does it work?

A system boiler is also known as a “sealed system”. It works on the principle of stored hot water, and it is designed for heating water from the mains immediately. Its specific feature is that many of the major individual components of the heating and hot water system, such as the expansion vessel and the pump, are built into this boiler. It contributes to quick, neat, easy and efficient installation.

In this construction  hot water is pumped through the heating system from the boiler right to the radiators and hot water cylinder, so that your house will heat up quicker, thus reducing the running cost.

what is a system boiler

Estimating Pros and Cons

The use of a system boiler gives you a considerable number of advantages. Some of them have already been mentioned, but consider also the following:

  • The boiler of this type has no tank, so no extra storage space is required. It is especially important if you have no loft or if your loft space is limited. The contemporary design allows you to install the boiler almost everywhere, from a kitchen to an open utility area.
  • The “dry loft” also reduces the risk of the tank and pipes leaks or frost damages.
  • As this type of boiler is high pressure, you can easily operate more than one hot tap or shower at the same time. The flow rate will not be reduced in any way, as it may happen with other boilers.
  • Such boiler is recommended for larger homes with multiple bathrooms or en-suites.
  • These boilers use less fuel, which makes them environmentally friendly as well as economical to run.

But of course as with all boilers certain problems may also arise, such as mentioned below:

  • Though  hot water is quite quick still it is not instant, you have to wait for a while; and you have to wait again for water to reheat once it runs out from the storage cylinder.
  • You still need space for the hot water storage cylinder, usually in the airing cupboard.
  • The boiler of this type may be considerably expensive to buy, install and repair.
  • It may be just not suitable for some houses due to specific reasons. To find those out an expert advice may be required.

To Rely on a Specialist or not?

Nowadays there exists a wide range of boilers, and one of them is sure to suit you best both in price and in reliability and performance. But remember that some minor details may influence the right choice, and the best thing you can do is get proper advice. It is especially important if you have never dealt with boiler installation and have no experience of your own. Most boiler manufacturers provide the services of a boiler installer free of charge. They visit your home, access the general situation and help to choose the boiler particularly meeting your needs. Or you may get a recommendation from a household energy consultant. Always remember that a boiler will have a drastic influence on the quality of life in your house. So choosing it without much experience and in haste is certainly not the best way to save time and money.