RADIATORS

A radiator is the part of the engine cooling system that excess combustion heat is lost to atmosphere by means of forced convection using a circulating liquid such as water or water/glycol to affect heat transfer.

WHAT DO THEY DO?

The primary function of the radiator is to transfer waste heat energy to the cooling air at a rate that will maintain the safe operating engine coolant temperatures. The processes that accomplish this are convection, conduction, and radiation. These processes are dependent upon 3 variables:

•    The existence of temperature differences between liquid and air
•    The existence of temperature differences between coolant and air flow
•    The design of the heat transfer surfaces to maximize their potential

RADIATOR CORE

The radiator core is the heat exchanger portion of the radiator assembly. It consists of three
parts:
•    Tubes
•    Fins (flat fin or tubular) or serpentine
•    Header sheet bonded together mechanically or metallurgically

TYPES OF CORE

•    Downflow
•    Crossflow
•    Low Flow
•    Split Flow
•    Folded

Higher incidence of cooling system trouble in older vehicles

Vehicles five years and older are prime candidates for cooling system troubles, troubles that could strike when least expected. NARSA experts report that cooling system service is most frequent on vehicles with more than 100000 km. However, NARSA experts note that the km on a vehicle is not as big a factor in the maintenance of a cooling system as is the vehicle’s age.

An aging vehicle has been exposed over time to environmental factors that can harm a car’s cooling system. Salt from ocean air, road salt, debris and other chemicals tend to break down the metal in a radiator core.

The radiator, an integral part of the cooling system, is designed to protect an engine from the destructive forces of too much heat. Heat is produced every time a vehicle is driven. That’s why it is so important to have your car’s cooling system, especially the radiator, checked at least once every two years.Radiator and cooling system specialists offer a variety of services, including flushing out radiator and cooling systems, repairing leaks and other damage to copper/brass and aluminum/plastic radiators, checking thermostats and fixing broken hoses or cracked belts. They can check for corrosion and debris and often may spot and address potential problems, helping to prevent emergency car repairs down the road.

Tips for keeping your vehicle cool while sitting in traffic.
A vehicle’s cooling system is designed to protect the engine from the destructive forces of too much heat. If the system isn’t in good repair, simple tasks such as sitting idle in rush-hour traffic can cause a vehicle to overheat even when temperatures drop below the freezing mark.

However, if you do get caught in traffic and you notice the temperature gauge beginning to rise, NARSA - The International Heat Transfer Association says there are some things you can try to keep your vehicle from overheating.
•    Give it a little gas. This will enable the vehicle to get rid of some of the engine heat.
•    Turn on the heater. The heater will draw some of the heat from the engine to the inside of
      the vehicle.
•    Turn off the vehicle. Once you safely have pulled off of the road, turn off the vehicle to let the       engine cool down.
•    Finally, have your vehicle inspected by a radiator specialist. Radiator specialists have expertise       in targeting cooling system problems, which could range from a clogged radiator core to low       engine coolant to an inoperable engine fan.

7-Point preventative cooling system maintenance program

A car’s engine generates enough heat to destroy itself. The cooling system, however, protects against damage by keeping the engine within the correct operating temperature range. That’s why preventative cooling system maintenance is essential in helping to ensure your engine’s life.

NARSA - The International Heat Transfer Association recommends that motorists have a seven-point preventative cooling system maintenance check at least once every two years. The seven-point program is designed to identify any areas that need attention. It consists of:
•    a radiator pressure cap test to check for the recommended system pressure level
•    a thermostat check for proper opening and closing
•    a pressure test to identify any external leaks to the cooling system parts; including the radiator,       water pump, engine coolant passages, radiator and heater hoses and heater core
•    an internal leak test to check for combustion gas leakage into the cooling system
•    a visual inspection of all cooling system components, including belts and hoses
•    a system power flush and refill with car manufacturer’s recommended concentration of coolant
•    an engine fan test for proper operation

By performing regular checks, NARSA radiator and cooling system specialists can help motorists prevent problems, emergency repairs and/or replacements, effectively saving the consumer time, trouble and money.

5 Most common radiator service procedures

Flush and repair. The radiator is removed from the vehicle, cleaned externally using a powerful spray gun and flushed internally. It is then pressure tested, inspected and repaired as needed.

Clean and repair. In this procedure the radiator is removed from the vehicle, cleaned externally and flushed internally by immersion in a specially formulated industrial-strength cleaner. It is then flushed a second time, pressure tested, inspected and repaired as needed.

Rod-out and repair. The radiator is removed, cleaned externally and flushed internally by
immersion. It is then pressure tested, inspected and repaired as needed. One tank is removed and a rod is inserted into each tube to remove debris. Once complete, the radiator is reassembled
and tested.

Newcore or recore. This technique brings a radiator up to or as close as possible to its original operating condition by using restored existing parts in combination with new, rebuilt or unimpaired parts. It always requires the installation of a new core.

Plastic radiator tank and gasket replacements. In this procedure the radiator is removed from the vehicle and placed in a special fixture to detach the damaged tank and/or gasket. The tank and/or gasket is replaced with a readily available new or restored part. Afterward, the radiator is reassembled and tested.

INDUSTRIAL COOLING

NARSA members service, rebuild and sell automotive heat exchangers of all types, large and small. The smallest would most likely be a heater from a passenger car or light truck. The most common would be domestic and import radiators from motor vehicles. The largest would be one-story-high industrial coolers weighing thousands of pounds.

Wherever there is a need for cooling, this is a need for a NARSA cooling specialist. In addition to service and parts, NARSA specialist can work with equipment owners, operators and maintenance professionals to design and install products to meet very specific cooling needs.

Most NARSA members (94%) provide heavy duty and industrial heat exchanger services. They service and sell: aftercoolers, air-to-air coolers, charge air coolers, intercoolers, plate coolers, tube and shell bundles, torque coolers, engine and transmission coolers and more.

You find these kinds of heat exchangers in an ever increasing number of applications and machinery used in agriculture, transportation, mining, food processing and storage, refining, manufacturing and drilling.