Boilers are definitely not the most common heating source for water or HVAC systems. Most modern homes have a separate water heater, and then a furnace for heating the air. Furnaces are connected to a duct system that is encased in the walls (which is usually drywall on modern construction). But, boilers can still be a very efficient alternative for many properties. The practicality of installing a boiler partly depends on how your home is built. It also depends on whether or not you are going to heat both your water and air with the boiler.
How Combination Boilers Work
Mini boilers are designed for shared or combination systems (these are different names for the same system). This basically means that the boiler can fulfill your hot water needs while using residual and unique heating elements to heat your air. A boiler functions by using fuel to create a fire, which heats up water inside pipes. This pipe system is circulated within the walls of a home, and it is separate from the pipes that circulate the water actually used around the house. So, some of the pipes will heat up the walls and go to the radiators, while other pipes are connected to your physical water connections (faucets, shower heads, etc.). Basically, there are heating pipes and water pipes (even though they both have hot water inside).
The heating pipes pump the hot water through walls, and to radiators which are on the outside of the wall so the heat can be controlled. When this water reaches the radiators, it is then recirculated back to the boiler to be heated up again as necessary. The radiator can be adjusted to give the homeowner closer control over the temperatures in each room.
As for hot water, the exact method for the distribution of the water depends on your system. Tankless systems basically have to produce the hot water whenever it is needed. System with tanks are better for large homes because they can store more hot water so you are less likely to run out. Obviously, when you are heating your home, while also using a lot of hot water, your boiler will be doing a lot of work. But, this is still more efficient than having a boiler and separate water heater running at the same time.
Combination boilers are great for most homes, and can be set up efficiently to heat buildings in any climate. For more information, contact a company like Rickett Industrial Environmental Systems.