2005 Mazda MPV - Heater Hose

What Are Car Heater Hoses?

Heater hoses move warm coolant from your water pump or engine through your heater core and back again to ensure coolant properly cycles through the heating system. The warm coolant in your heater core provides heat for your vehicle's cabin, and the blower motor blows air over the core's heated fins before it reaches the vents. Heater hoses are made of rubber or plastic, and may be secured with hose clamps or specialty quick connectors that might require a specialty disconnect tool to remove. Like all hoses, heater hoses and their fittings can wear out over time from constant exposure to hot temperatures. The rubber of the hose can dry out, crack, or split, and plastic heater hose lines can also experience wear that can lead to leaks. Since one end of the heater hose goes to your cabin, you may see leaks at the back of your engine compartment, and in extreme cases, you might even notice antifreeze in your floorboard. A damaged or clogged heater hose or heater core could also cause your heater to fail to work as it should - but this may also be due to a clogged or damaged heater valve or other factors. If you have a coolant leak or low coolant levels, and especially if your cabin isn't getting warm, check the condition of your heater hoses. If you notice any damage, or if the heater hoses are especially spongy, brittle, show signs of cracking, or have other wear, they should be replaced to prevent an untimely breakdown and overheating. O'Reilly Auto Parts carries replacement heater hoses, hose clamps, fittings, coolant, and more to help you complete your repair.