What is Heating, Explain heating, What is heating theory
What is heating speaks to explain heating and what is heating theory in a building.
Heat exchangers provide either heated water or heated glycol for various building mechanical heating components. Heat exchanger theory is that each heat exchanger will have a primary and secondary side.
The primary side allows for the flow of the primary heat source through it and provides heat.
The secondary side of the heat exchanger allows for the flow of secondary water or glycol through it and picks up the exchanged heat in a controlled manner.
A heat exchanger may be:
water to water.
water to glycol.
steam to water.
steam to glycol.
Radiation Heating Water System
The convector radiation heating equipment is used to transfer heat to the perimeter of the building. The finned convectors are located throughout the building, wall mounted on the perimeter of the exterior rooms.
The convector radiation heating system may consist of:
wall mounted thermostat either electric or pneumatic.
convector mounted self contained thermostatic valve.
control valves either modulating or electric two position.
Radiation Heating Water Temperature Control Loop
A control sensing supply water and outside air temperature may be provided to vary the heating water temperature supplied to the system.
The control will modulate a mixing valve which mixes supply and return water to achieve the necessary temperature.
As the outdoor air temperature increases the heating water supply temperature decreases. As the outdoor air temperature decreases the heating water supply temperature increases.
A common reset schedule is at -30 F outside air temperature the supply water temperature is +180 F and at +60 F outside air temperature the supply water temperature is +85 F.
Ceiling Hung and Cabinet Unit Heaters
The purpose of the ceiling and cabinet unit heaters is to provide heating for the immediate area in which it is located. The heater uses 100% return air for ventilating purposes.
There are many types of unit heaters:
gas fired unit heater.
hot water unit heater.
electric cabinet unit heaters.
The unit heater unit may consist of:
electric or pneumatic wall mounted thermostat.
hot water coil.
gas fired burner section.
supply air fan.
Fan Coils and Ducted Force Flow Units
The purpose of the fan coil and the ducted force flow unit in the secondary heating circuit is to provide heating and cooling for the immediate area in which it is located.
The fan coil uses 100% return air for ventilating purposes.
The fan coil heating section may consist of the same equipment as listed for the ceiling hung and cabinet unit heaters. The fan coil may also have a cooling coil which can be a chilled water coil or a direct expansion cooling coil.
The fan coil will also have a supply air fan and automated controls.
I hope this explain heating information is helpful.
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