This happened to us on our Toyota. We had to replace the Thermostat. But make sure you follow the directions carefully b/c if it is not put in a certain way it will not work properly.
What is your coolant level? If it isn't full, make it full.
The thermostat may be stuck open. It is supposed to close when the temp falls below normal.
Outside temperature is a factor. In extreme cold, the radiator will cool much quicker.
Bad head gasket. If the head gasket is weak, it may allow engine coolant to seap into a cylinder and be thrown out through the exhaust. The engine may operate normally but there would more than likely be little or no heat and you would see white smoke coming from your tail pipe.. alot of smoke. (had this happen before).
All the other answers could cause it. Also not mixing the proper ratio of water to anti-freeze or using straight anti-freeze can cause it.
This is a good question and some of the answers are good, however i don't agree with using straight anti-freeze. I perfer to use straight anti-freeze and that's all we use at the radiator shop that i have worked at for the past 10 years. I think the biggest answer that's been over looked it that your heater core could be plugged up. This is usually easy to diganose. If the engine is up to temperature BOTH hoses going to it should be hot to the touch. If one is cold and the other is hot, your heater core is plugged up. The easiest way to fix this yourself is to go to a car wash that has a wand that u can use. remove both the hoses that go to the heater core and "flush" it out both ways with the wand. Be care full cause to much pressure can make the heater core leak. As far as the thermostat being stuck shut that problem that's easy to diganose also. If the engine is up to temperature the top and bottom radiator hoses should be hot to the touch. If one is cold and the other is hot then there is not proper anti-freeze flow and you need to replace the thermostat.
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all good answers : also make sure your radiator cap is sealing if not most heat will escape as engine is running..
Possibilities include: a thermostat that has failed in the open position, low coolant level, air trapped in the coolant system, and a clooged or bad heater core. If your thermostat and coolant level are fine, and you don't have anitfreeze coming out of your cabin heater vents ( this indicates a leaking heater core) or dripping on the floor, I would try flushing out the heater core with a simple old garden hose. It worked like a charm for my mothers car. Keep up with coolant flushes to keep the system clean of dirt and corrosion.
all very good answers!!!, you have to remember that also if you have a bad thermostat that ( all ) of your emission devices they too will not operate the proper way, so as far as if your thermostat goes if it is bad not only no heat but bad operating emission devices, i learned that the hard way... .
Two things it can be:
1) Thermostat needs replacing. If it was warm out, your car would probably overheat
2) Heater core needs replacing.
3) Thermostat stuck open, need to burp system. Open radiator cap, squeeze big rubber hoses a few times. Run engine, let it heat with cap open. Shut down and squeeze hoses some more. Do a few times if necessary. Air bubble at thermostat prevents operation. Or try a different thermostat brand, with different bleeder valves.
Usually there is blockage in the heater. Most vehicle heaters are just a very small radiator and block fairly easily. Remove both tubes and try blowing it out with a regular garden hose, or just remove the heater core and replace,
A plugged up heater core is one possibility another could be a faulty thermostat and another (depending on the vehicle) a faulty temp blend door actuator. One way to determine the cause of poor heat from the heater would be to warm the engine up to operating temperature and with engine still running and hood open, put your hands around the heater hoses one at a time. If you have a plugged up heater core you will feel one hose is hot and the other hose is warm (poor circulation because of blockage). If you have a faulty thermostat, both hoses will feel only warm. If you have a faulty blend door actuator, both hoses will feel equally hot.
It can be caused by a number of things. Clogged radiator, stuck thermostat, inoperable cooling fan, defective water pump, blown head gasket, or a combination of the above.
low water, bad thermostat, vacuum door not working, clogged up heater core, heater valve broken........
These are two separate systems; if neither is working, the cause might be a blown fuse or circuit breaker, perhaps the one that controls the blower.
The 1939 Packard was the first car with a true air-conditioning system.
The most common case of air conditioner failure in cars is the failure of the condenser, a major component of the air conditioner. If you can get this fixed at an automobile store, then you will not have this problem.
If the temperature is below freezing outside, there is no need to run the air conditioning. The heater does not use the same set up as the air conditioning. This may be a built in feature of the car so the compressor does not completely freeze up. As air conditioning is running, freon passes through the compressor, making it quite cold internally.
The evaporator is part of the ac system. It removes heat energy from the air.
It is a very involved procedure. Get a manual on your car from the parts store or from AUTOREPAIR2000.COM
The refrigerant change of state is what causes the heat transfer. The refrigerant is a low-pressure liquid when it's in the evaporator, which absorbs heat from the air, cooling it. The absorption of the heat causes the refrigerant to boil (change state from liquid to gas). The gas is then brought to the condenser in the front of the car where it cools (rejects heat out) and condenses back to a liquid.
The chemical in the air conditioning unit needs replaced.
The air comes from the air outside and the air conditioning system in the car turns this into cold or warm air.
The 1939 Packard was the first car with a true air-conditioning system.
No, Air conditioning actually makes the car's engine work harder causing to heat up more. To get a demonstration of the process, put your hand over the top of your outside air conditioner when it is running. Air conditioning is a heat movement. It's moving heat from inside your car to the outside. This heat is removed right in front of the radiator, so your csr runs hotter.
That is the normal sound of the pressure equalizing in the system.
Clean or replace your Idle Air Control Valve.(IACV)
Automotive air conditioning is the ac unit in your car. It's what "conditions" the air in your car, ie keeping the temperature inside the car cool or warm.
No use for exhaust in car air conditioning
Allows heat absorbed by the oil to be exchanged with the air that passes through the fins of the cooler. Air conditioning condensers and car radiators work the same way.
The steam could be coolant from a bad heater core.
all i know is that freon is put into air conditioning units in your car. it's what causes your A/C to be cold