Ads
related to: boiler flow and return temperature control switch replacement
Search results
Results From The WOW.Com Content Network
This limit controller may shut the furnace off if the blower fails or if something is blocking the air flow. The heated air is then sent back through the home through supply ducts. In larger commercial applications, central heating is provided through an air handler which incorporates similar components as a furnace but on a larger scale.
The back boiler is typically used with a gravity feed circuit to the hot water cylinder, with a vent or overflow to prevent excess pressure build up.It can also be connected to a series of radiators to provide central heating but usually requires an electrical pump to be fitted to circulate the hot water, some systems can use the gravity circuit to include radiators.
The control system can compare the temperature of the outside air vs. return air, or it can compare the enthalpy of the air, as is frequently done in climates where humidity is more of an issue. In both cases, the outside air must be less energetic than the return air for the system to enter the economizer mode.
Unlike the switch-monitored electrical zone valves, these valves automatically return to the default position without the application of any power, and the default position is usually "open", allowing heat to flow. Highly sophisticated systems may use some form of building automation such as BACnet or LonWorks to control the zone valves.
Low-water cutoff: It is a mechanical means (usually a float switch) or an electrode with a safety switch that is used to turn off the burner or shut off fuel to the boiler to prevent it from running once the water goes below a certain point. If a boiler is "dry-fired" (burned without water in it) it can cause rupture or catastrophic failure.
A thermostat exerts control by switching heating or cooling devices on or off, or by regulating the flow of a heat transfer fluid as needed, to maintain the correct temperature. A thermostat can often be the main control unit for a heating or cooling system, in applications ranging from ambient air control to automotive coolant control.
Ad
related to: boiler flow and return temperature control switch replacement