Press "Enter" to skip to content

What determines enthalpy change?

What determines enthalpy change?

The change in enthalpy of a reaction is a measure of the differences in enthalpy of the reactants and products. The enthalpy of a system is determined by the energies needed to break chemical bonds and the energies needed to form chemical bonds. If so, the reaction is endothermic and the enthalpy change is positive.

What does an enthalpy sensor do?

Single Enthalpy Economizer – These use a sensor to determine if the outdoor air contains a low enough amount of humidity to use for cooling. Single enthalpy controls have been known to have problems. Over the years, elements used in these types of sensors sometimes break down, rendering the sensor inaccurate.

What is an economiser in HVAC?

An economizer is a part of a building’s cooling system that uses cool outdoor air to cool the building instead of operating the air conditioning compressor. An economizer is an add-on feature to an HVAC air handler that draws in outdoor air and mixes it with return air from indoors.

What is economizer cycle?

A forced-flow, once-through, convection-heat-transfer tube bank in which feedwater is raised in temperature on its way to the evaporating section of a steam boiler, thus lowering flue gas temperature, improving boiler efficiency, and saving fuel.

What is the main purpose of an economizer?

Economizers (US and Oxford spelling), or economisers (UK), are mechanical devices intended to reduce energy consumption, or to perform useful function such as preheating a fluid. The term economizer is used for other purposes as well.

How does an air side economizer work?

Description. An air-side economizer (see Figure 13 below) brings outside air into a building and distributes it to the servers. If the outside air is particularly cold, the economizer may mix it with the exhaust air so its temperature and humidity fall within the desired range for the equipment.

How much energy does an economizer save?

Energy Savings When economizers are properly installed and maintained, they can reduce mechanical cooling by up to 75% in certain climates.

What is a water side economizer?

For data centers with water- or air-cooled chilled water plants, a water-side economizer uses the evaporative cooling capacity of a cooling tower to produce chilled water and can be used instead of the chiller during the winter months. This can reduce the risk of data center down time.

What happens to the flash gas formed in a chiller economizer?

What happens to the flash gas formed in a chiller economizer? The refrigerant will immediately flash and the chiller will freeze up and the tubes will crack to cause extensive damage to the chiller.

What is a water side?

(Entry 1 of 2) : the margin of a body of water : waterfront.