If the thermostat is bad would it cause the heater core to not work properly?
I have read online that if the hoses leading to the radiator from the thermostat are cold then that means the thermostat is bad, but would that be the reason why my defrost doesn't work properly? When I start the vehicle I smell what could be antifreeze, just not sure if I should jump to replacing the heater core or hope the thermostat dose the trick.
Experienced mechanics share their insights in answering this question :
Hello – you are correct. If the thermostat is stuck open, not allowing the engine to warm up properly, there won’t much, if any, heat in the passenger compartment. However, if you are smelling coolant in the passenger area, chances are the heater core is leaking as well – not a happy occasion. I would recommend a heater inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, confirm this diagnosis, and give you an accurate assessment of damage and cost estimate for repairs.
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A thermostat prevents the coolant from flowing until the motor gets warm enough. Rubber hoses carry the coolant from the motor to the radiator, and also to the heater core, which is basically a smaller radiator under the dashboard.
A malfunctioning thermostat, no matter what kind it is, can cause a number of problems for your heater, ultimately hurting its effectiveness and efficiency. For instance, a thermostat sending incorrect signals—or no signals at all—can result in a heater that won`t even start up.
A faulty or broken thermostat is the most common cause of your car`s failing heat. Stuck open or stuck closed, the part can not only cause issues with your heat but also with your engine`s cooling system.
If you turn on the system and don`t feel any warmth, it`s possible that the heater core is not functioning properly. Other signs of a failing system include a coolant leak, a sweet, syrupy smell inside the cabin, foggy windows, and an overheating engine.
To get there as quickly as possible, the thermostat closes to keep the coolant inside the engine from travelling through the entire cooling system. Once the engine warms up enough, the thermostat opens. That now-warm coolant circulates into the heater core to keep you toasty.
Normally, the heater wires directly to the line voltage. The thermostat, on a separate circuit, connects to the breaker with another wire connected directly from the heating unit. If the thermostat is low voltage, relays or transformers may be required.
If the thermostat goes bad, it can cause the HVAC system to switch on and off irregularly. This results in places closer to the HVAC system getting more cool/hot air, with rooms furthest away getting barely any. The Interface Won`t Respond.
The heater control valve (sometimes called the hot water valve) is used to control the rate at which coolant flows through the heater core. The valve is located on the heater inlet hose. Manually operated systems may use a cable, a vacuum motor or an electric solenoid to operate the valve.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
If the thermostat is bad would it cause the heater core to not work properly?
ANSWER : Hello – you are correct. If the thermostat is stuck open, not allowing the engine to warm up properly, there won’t much, if any, heat in the passenger compartment. However, if you are smelling coolant in the passenger area, chances are the heater core is leaking as well – not a happy occasion. I would recommend a heater inspection by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, confirm this diagnosis, and give you an accurate assessment of damage and cost estimate for repairs.
Would a blown coolant hose, at heater core, cause loss of power?
ANSWER : Yes, severe overheating will cause loss of engine power and also has a high potential to damage the engine as the pistons scuff the cylinder walls and the exhaust valves stick in the valve guides. If the overheating is severe and prolonged, loss of cylinder compression can occur. To get some idea of the present condition of the engine you can do a compression test on each cylinder and see how the results compare to factory specifications. With regard to the cooling system leak, if you already know the source of the leak, that should be easy to repair. If you do not know the source and/or you want the entire cooling system pressure tested for leaks simply request a cooling system leak diagnostic. Please note that the engine cooling thermostat can be damaged by the high heat that occurs during overheating and it should be replaced. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
Heater not working reliably, is it caused by a bad thermostat?
ANSWER : From what you’ve described, it sounds like you have a stuck open thermostat. I’d recommend replacing the thermostat to see if this is the cause of the slow heat up of the vehicle since it’s a relatively quick repair. In an area like that it sounds like you’ll will need the heat in the winter very badly and as soon as possible. I would also recommend getting a coolant flush as it may help clear any possible blockage in the heater core. To avoid any unnecessary repairs, consider YourMechanic, as one of our mobile technicians can come to your home or office to diagnose your heating issue and make the necessary repairs.
Car overheats. Replaced thermostat, overflow cap, heater core. car was blowing cold air, massive leak from heater core hoses.
ANSWER : Of course, be sure it is not just a temperature sender and/or gauge malfunction. If there is trapped air in the cooling passageways that can cause overheating. There are a few other common causes of overheating, namely a faulty thermostat (inapplicable in your case although be sure you used a genuine OEM thermostat), a plugged radiator, collapsed hoses, non functioning cooling fans, and a faulty water pump or drive belt. Certain engine faults, such as a leaking head gasket or poor engine running condition can also cause overheating. If you desire that this problem be diagnosed by a certified Mechanic, dispatched by YourMechanic right to your location, please request an engine overheating diagnostic and the responding certified mechanic will get this resolved for you. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.
Heater / A/C are not working properly. They are weak and the highest and lowest settings do not work at all. Any ideas what it could be?
ANSWER : Hi there. Check the power from the switch on each setting and to the blower. See what the voltage is at each setting. If the voltage is low or not showing, then the switch is not working and needs replaced. The switch has a resister built in it to make the blower have different voltage outputs which makes the blower have multiple speeds. However, the first setting and the last setting could have a burned element inside making only the second and third setting work. Once you have the blower working properly, if there is no heat, then check the heater control valve in the engine compartment for if the vacuum line has came off or if the valve is not working. When the engine is at operating temperature, check the temperature of the coolant hoses to the valve and after the valve. If the hoses are the same temperature and the valve is shut, then the valve is on or not working. If the temperatures are different, then the valve is off or not working. If you need further assistance with your heater and a/c not working, then seek out a professional, such as one from Your Mechanic, to help you.
Heater not working properly leaking fluid and overheating
ANSWER : Hi there. Your heater isn’t working and your car is overheating because of a low coolant condition. Your low coolant condition is due to the coolant leak. Flushing anything will not correct the situation. A properly executed cooling system pressure test will identify the leaks and a repair process can be determined afterwards. I strongly suggest having a qualified technician perform an inspection to avoid replacing unnecessary parts. Your Mechanic has several technicians available that can assist you with a coolant is leaking inspection.
Is my heater core bad or condenser?
ANSWER : Hi there, thanks for writing in about your 2008 Ford Escape. The first thing you need to do is to check your coolant level when your truck is cold. Do this by removing the radiator cap. The radiator cap on your car is part of the expansion tank. If it is low, the coolant leak should be found and repaired. When your checking the coolant level, take note of the condition of the coolant. It should be clean and the color should be bright. Ford coolant is often yellow, but it may have already had the coolant replaced at one time and it could be green. The main thing is it should be clean.
Taking note of the coolant condition, color, and clarity is important in determining if the wet carpet is from coolant or water. Coolant will be oily to the touch. It will be slick between your fingers. Water will be clear and not oily. I don’t recommend trying this, unless the coolant looks like mostly water, but coolant tastes sweet. Of course it is toxic, but a small taste will not hurt you. Again, I only recommend this if you are unable to absolutely determine if it is water or coolant on the floor.
If it is coolant, then yes, your heater core is leaking. If it is water, then there are three things that could be happening. It is very common for the evaporator drain to clog and for water to fill up the evaporator case and eventually leak onto the floor. The drain is inconveniently located on the fire wall. just to the passenger side of the center of the vehicle, under the hood. There will be a black rubber elbow hanging off of it. This elbow can be removed if necessary. It usually takes a wire of some sort to dig out whatever debris is clogging it. Sometimes, if your lucky, you can access it from under the passenger side dash.
If the drain is clear, it could be a water leak from rain. These are notoriously difficult to locate. In the past, I have set a sprinkler on top of the car to find a water leak from rain.
The third possibility is the evaporator could be holding water. This is usually because the water that would normally drip off of it is freezing to it externally. If this is occurring, there is something wrong with the A/C system and it will need to be diagnosed by a technician.
Heater blowing lukewarm air. Had thermostat and gasket changed plus heater core back flushed. No change.
ANSWER : The heater is reliant on the engine temperature getting up to and maintaining normal operating temperature. Once this is verified then you can check both heater hoses in and out of heater core with blower on low speed and heater on full hot. The two hoses should be hot and close to same temperature. Then put blower on high speed and check temperature out of vents and check both hoses again. The temperature of inlet hose will be hot and out let hose lower temperature since blower is on high. If you have good temperature of engine then heater core flow or air flow is not good. The temperature blend door actuator and core fins blockage are the most common causes of the problem.
