Why is my car blowing cold air when the heat is on?
by
Low Coolant Level
The coolant (usually a mixture of water and antifreeze) in your engine doesn’t just work to keep the engine from overheating: It’s also the source of heat supporting the heating system. If there isn’t enough coolant in your system, the heater core will blow cold air into your car.
Here are the most common reasons why your car heater isn’t blowing hot air. Low coolant: Whether caused by a leak or water evaporation, low coolant is the most common source of poor heater output. Thermostat: A stuck-open thermostat prevents the engine (and coolant) from heating up.
Two of the most common causes of electric furnace or heat pump failure are blown fuses and frequently tripping circuit breakers.
How do you diagnose a heater problem?
Use these steps to troubleshoot your car heater.
Check the Coolant. Low coolant can’t reach the heater core and generate warm air.
Assess the Heater Core. Make sure heater hoses are in good shape.
Inspect the Water Pump.
Listen to the Fan.
Look for Blown Fuses.
Why is my car blowing cold air when the heat is on? – Related Questions
Why is my heater running but no heat?
When you turn the furnace on but no heat comes out, there may be an obstruction. Dirty air filters restrict airflow, which can make it feel like not much heated air is coming out of your vents. Check the furnace filter and replace it if its surface is covered with contaminants.
How do I reset my heater?
How to Reset an Electric Furnace
First, turn off the power supply to the furnace by turning off the breaker in the circuit box.
Locate the reset button on the furnace and press it to reset the furnace.
If the button is popped up, press it down.
Return the cover to the blower compartment and turn the power on.
How do you tell if you have a clogged heater core?
A noticeable difference in airflow could indicate that the heater core fins have been clogged and are restricting airflow.
Heater core failure symptoms
Weak or no airflow.
Cold air (not warm) coming through the vents when the heater is on.
Coolant leakage visible inside the cabin or a damp smell.
What are the symptoms of an failure heating system?
The most common indicators of a heating system malfunction include:
Strange smells. A smell of burnt dust is not typical of a properly functioning heating system.
Thermostat indicators.
Strange sounds.
No heat.
System won’t turn off or turns off and on frequently.
How do you know if you have heater core problems?
Sweet Smells in the Car
It could be the heater core. If the heater core is leaking, it will blow the odor of engine coolant through the vents. Coolant smells sweet, almost musty. Many people say it smells like candy, fruit, or maple syrup.
What are signs that your heater core are going?
Common symptoms of a bad heater core include lack of heat, frequent loss of coolant, and an overheating engine. Your car’s heater core is responsible for keeping you warm in winter, heating the air in your vents, and preventing your defroster from getting, well, frosty.
How expensive is it to replace a heater core?
The total cost of parts and labor will range between $800 and $1,000 to have your heater core fixed by a professional. Labor costs vary, so call ahead and get a quote from multiple repair shops.
How much does it cost to fix heater in car?
Based on whether you fix the car heater core yourself or with the help of a professional, the cost to fix it varies. Suppose you fix it by hiring a professional, the total cost range between $800 and $1,000. For fixing the issue by yourself, the cost ranges from $100 to $300.
To clean the blockage, you need to flush water or air through the heater core. By doing so, the grime and dirt that’s causing the clog will come out through the inlet hose. Now, insert a water hose into the outlet hose. If you have access to an air compressor, you can use that to push out the coolant and grime.
How do you unclog a heater core in a car?
What happens when heater core is clogged?
While your vehicle’s heating system needs coolant to warm the interior, the engine needs coolant to keep it from overheating. If there is a clogged heater core, it will keep the coolant from flowing through the engine, causing it to overheat.
Can a clogged radiator cause no heat?
Poor Internal Heating : A clogged cooling system and heater core could lead to lack of heat inside the vehicle due to the inability of the hot engine coolant to pass through the heater core.
How do I know if my radiator is partially clogged?
5 Symptoms Of A Clogged Or Bad Car Radiator
Temperature Gauge Reading Higher Than Normal: The temperature gauge indicates the temperature of a car coolant.
Radiator Leaking Coolant:
Radiator Hose Troubles:
Coolant Color Change:
Radiator Fins Bent or Broken:
How can you tell if you have a blown radiator?
Four Signs You have a Bad or Failing Radiator
Your vehicle is overheating. If your vehicle constantly overheats, especially under normal driving conditions, this is one of the most common signs that your radiator is bad or failing.
Your vehicle is leaking coolant.
Sludge build up in your radiator.
Low coolant levels.
How do I know if my air is trapped in my radiator?
Carefully check each radiator to ensure it has an even temperature across the whole surface area. If you do find any radiators that are cold at the top or hear any gurgling noises, it’s a good indicator that there’s trapped air inside and that you’ll need to bleed it.
How do I unblock air in my radiator?
Step 1: Turn off your central heating and wait for around 20 minutes for the system to cool down. Step 2: Lay a dry cloth or towel beneath the radiator you want to bleed, just in case any water escapes. Step 3: Use your radiator key to slowly open the valve, turning it anti-clockwise to do so.