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heat sink

Glossary “heat sink” Definition:
1). A finned, aluminum housing that dissipates heat and serves as a base on which electrical components, such as semiconductor devices, are mounted. 2). A heat dissipating section of the alternator that holds the insulated diodes or all the diodes, and carries heat away from the devices.

heat tab

Glossary “heat tab” Definition:
A small aluminum disk attached to the cylinder head or block having a lead center designed to melt at 260¡ãF, to indicate if the engine has been overheated.

heat riser

Glossary “heat riser” Definition:
A channel in an intake manifold through which exhaust gas flows in order to heat the manifold, thus aiding in fuel vaporization.

heat riser valve

Glossary “heat riser valve” Definition:
Control valve between the exhaust manifold and exhaust pipe that restricts the flow of exhaust, causing it to flow back through the heat-riser channel under the intake manifold. It acts as an aid to fuel evaporation and to speed engine warm-up.

heat load

Glossary “heat load” Definition:
The “load” imposed on an A/C system. due to ambient temperature, humidity, and all other factors that produce unwanted heat.

heat quantity

Glossary “heat quantity” Definition:
1). Amount of heat as measured on a thermometer. 2). Amount of heat contained in an object measured in Btu’s or calories.

heat range

Glossary “heat range” Definition:
Measurement of a spark plug’s ability to transfer heat from the tip of the insulator into the cylinder head.

heat exchanger

Glossary “heat exchanger” Definition:
Apparatus in which heat is transferred from one medium to another on the principle that heat moves to an object with less heat.