The “gas fired” part of this type of heating is very clear. This type of heating system burns fuel sources that are kept under constant low pressure. There is an installed pressure regulator that keeps the pressure at a constant.
The field of hydronics is an area that transfers heat through a medium. These mediums can be water mineral oil or glycol. Hydronic systems may involve the use of a chilled and a heated water loop. Boilers may be called into play and the system may use a chiller boiler system.
A hydronic system may be a forced flow or gravity flow system. It may be classified according the levels of temperature and pressurization. Also, the type of piping and pumping arrangement may define exactly what kind of system is in place.
Putting It Together
The heat that is created in a gas fired hydronic system is transferred through a boiler wall. This travels through the water where water temperatures are assessed by a temperature and pressure sensing element. The sensing element is connected to the electrical system and will turn the burner on when the temperature falls below acceptable levels.
A pilot light or an electronic ignition systems lights the burner. The by-products of the combustion will be channelled to the exhaust pipe or chimney. To keep pressures constant in the combustion chamber, a air break is used.
Thermostats control the action in this system and will engage a water pump that keeps water circulating to radiators and back to the boiler. There is a high limit control attached to the warm water outlet of the boiler. When appropriate and called for temperatures have been reached, the gas will be turned off. A pressure release valve will prevent the build up of dangerous levels of pressure in the system. At the highest position is located an expansion tank that allows the water to expand and contract as temperatures change.
One the latest technologies combines a hydronic system with geothermal heating. Geothermal systems are very economical. In a combination of these two, water is heated that comes from the ground. Heat is transferred to another water system and eventually lands at the coil. The water inside the coil is at a higher temperature and air that is blown over it by a fan is blown into a duct system. To make the same space cooler, the process is reversed. These systems are expensive installs. However, data indicates that over time, these type systems will save a home or business owner a significant amount of money.