Heating & Cooling System Service

Introduction to the Heating & Cooling System

The heating and cooling system, also known as the HVAC (heating, ventilation, and air conditioning) system, is responsible for regulating the interior temperature and providing comfort for the vehicle occupants. It consists of components such as the heater core, radiator, air conditioning compressor, blower motor, and various ducts. In colder weather, the heating system warms the cabin by utilizing heat from the engine coolant. In hotter weather, the air conditioning system cools and dehumidifies the air. The HVAC system ensures a pleasant driving experience by maintaining a comfortable temperature inside the vehicle, regardless of the outside weather conditions.

Importance of Coolant

Coolant, also known as antifreeze is the liquid that absorbs heat from the engine and circulates it through the heater core to heat the cabin and through the radiator to cool the engine. As coolant circulates through the system, it first transfers heat to the heater core to keep you warm and defrost your windows and then to the radiator and into the air. The liquid is cooled via a radiator fan and the air flowing in from driving down the road. Coolant is then fed back to the engine through the radiator hoses, heater hoses and the rest of cooling system, and the cycle repeats. Coolant should be checked for both pH levels and strength at regular intervals, then serviced accordingly. Even so-called long-life coolants have been known to lose their effectiveness prematurely. See your owner’s manual or call one of our service advisors for more information. Low and used coolant also causes your vehicle to be less fuel efficient. In some cases this can decrease your miles per gallon by up to 10%. If your coolant is left unchanged for too long, this may result in a chemical condition known as electrolysis, which can damage critical components like your water pump, radiator, thermostat and heater core which can result in costly repairs, breakdowns and even engine replacement. From a safety standpoint, an overheated engine won’t pose a problem for other motorists, but it could leave you stranded with no warning. From an environmental point of view, there is significant impact. Leaking engine coolant is poisonous and could be ingested by children, pets and other animals.

Check out our video and blog on the Heating & Cooling System by Auto Care Plus Owner, John Manelas, here. 


Cooling system failure is the most common mechanical failure. The results can range from inconvenient to extremely expensive. You can head off most cooling system problems with regular coolant replacement and cooling system inspections. If you see green, amber or yellow fluid under your vehicle, bring it in for an inspection.



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Auto Care Plus, LLC, Auto Repair & Service, Merrimack, NH

13 Locations Throughout NH, ME, & MA:

Manchester, NH

991 Candia Road | Manchester, NH 03109
(603) 232-1521

Merrimack, NH

738 D.W. Highway | Merrimack, NH 03054
(603) 429-1002

Hooksett, NH

1112 Hooksett Rd | Hooksett, NH 03106
(603) 644-7238

South Portland, ME

509 Westbrook St. | South Portland, ME 04106
(207) 773-8560

Wolfeboro, NH

635 Center St. | Wolfeboro, NH 03894
(603) 569-1068

Conway, NH

675 White Mountain Hwy | Conway, NH 03818
(603) 447-3873

Derry, NH

418 Island Pond Rd, Bldg #3 | Derry, NH 03038
(603) 845-3900

Lebanon, NH

258 Mechanic St, Lebanon, NH 03766
(603) 448-1381

Dover, NH

28 Sumner Dr, Dover, NH 03820
(603) 742-8627

Londoneryy, NH

107 Nashua Rd, Londonderry, NH 03053
(603) 404-5120

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