Boilers: A Homeowner’s Guide To Heating With Hot Water

Boilers are used in hydronic heating systems. They use electricity, gas, or fuel oil to produce heat. This heat is transferred to water which is then circulated for warming building and producing hot potable water.

Atmospheric Boiler

These units take conditioned air from the home and use it as part of the combustion process. This means that the air used to fuel the furnace is then replaced with unconditioned outside air. The energy lost in heating the new air makes this type of boiler the least efficient.


Sealed Combustion BoilerThis air that is required to burn the gas is called combustion air. This air must be replaced with unconditioned air from outside the home which in turn must be heated. This is called an atmospheric unit a

A sealed combustion unit brings air in from outside your home to use in the combustion process. They can be up to 10% more efficient than atmospheric units.


Condensing Boiler

These units extract more heat due to the design of their heat exchangers. Their efficiency is >90%. The exhaust from these units is cool enough to be vented with PVC pipe. Some of these units can be coupled with an indirect fired water heater to provide for your family’s hot water needs.

Some of these units combine the features of the condensing units with modulating capacity. Modulating capacity is where the unit senses the load on the system and adjusts the amount of gas it is burning. This eliminates a lot of cycling of the unit on and off.

Advantages/Disadvantages of Having a Boiler…

The biggest advantage of using a boiler to heat the home is the fact that it provides a more consistent room temperature than a warm air furnace. Piping arrangements may be configured to create zones which allow for individual temperature control


There are some disadvantages to using these units to heat your home: not only can they be very expensive to install in a new home, but in addition to that, the price of copper has risen sharply in the last several years. Therefore, the cost of the radiators and piping system has increased drastically. This can be overcome with in floor radiant heating systems. These systems use cross-linked polyethylene (PEX) tubing instead of the standard copper pipes and radiators.


If you use hot water for heat and you want to have central air, you have to install a separate system. Therefore, it is usually more practical to use another type of heating system.


Lincoln Heating & Air Conditioning commonly recommends a variety of boiler manufacturers. Because the right choice is situational we give the recommendation on a case by case basis.