from below the heater
An air sensing or air flow switch will do the job to prevent the heater from operating is there is no air flow from the fan.
The heater does not blow air because it emits infrared rays that have heat molecules within them, thus releasing heat, not blowing it. A heater does not blow air becasue there is no moving air source within the heater. The heater emits infrered rays that cause heat to slowly flow out of the heater.
No air flow from the heater duct of an 88 Chevrolet Corvette is often caused by a defective blower motor. A blocked air inlet or defective switch can also cause this issue.
As the water begins to flow within the system, the components inside the heater compartment ( the pressure switch)senses that flow and if your heater is calling for heat it will fire. When that water ceases to flow those same sensors tell the heater to stop firing. Built in safety devices. Ken
If there is no fan to pull the air in, fresh air must come into a convector heater from below. It is drawn in because the air heated by the heating element is warmer and therefore lighter than the colder air below it. So the warmer air rises to leave the convector heater from the top.
from the air in the vent to the air in the room
on top of heater housing
The best bet is that the valve that controls the flow of water to the heater core is not functioning, but on some cars it's the flaps that control the air flow through the core.
there is a little electric motor located under the dash on the heater box it opens a little door in there that directs the air to the defroster, vents, under the dash etc. those are bad about going out. If air flow is reduced when a/c is on- could be an incorrect refrigerant charge - causing the evaporator to "Freeze" When you shut of system evaporator has a chance to defrost restoring air flow. Try turn vent only on when air flow is reduced to see if evaporator defrosts and air flow restored
If there is a restricted air flow through a heater, yes a heater can get hot enough to start a fire.
Your thermostat is most likely bad. It controls the flow of warm water into your heater core which warms your air. Its a common problem in winter and an easy fix.
From the bottom, unless there's a fan ... in which case it flows in from behind the fan.
Air flows through the heater core to warm it up. Assuming the heater core is circulating water from the radiator, the problem is usually with the blend doors. These doors regulate air flow through the heater core and when they break, they usually block the input into the heater core and kill the heat. Check heatertreater.net for diagnostic information and an inexpensive fix.
If the flow is 100m3/hrs and line size is 2''
Heat control is by air flow control doors in the a/c and heater box. There is no water valve.
Of course it affects the air conditioning,,,it also affects the heater. Any time u have a restricted air flow it affects how heater and air conditioning works, for the worse. Engineers have designed the heater/ac system to run on clean air, so therefore your heater/ac systems work faster and better with a clean filter. Not to mention your own physical health by breathing clean air.
In Subarus the temp control for the heater does not control the coolant flow, just airflow past the heater core. If you get no heat, there is no coolant in the heater core -- either there is no coolant or it is not circulating.
Probably the heater core, it is a beast of a job to do, but is gratifying to say the least. If the is a smell of antifreeze you can almost bet it is the heater core.
air door not moving or air pocket in system..check that both hoses to heater core are hot, if not u have a problem with flow such as previous suggested or bad water pump or thermostat. if both are hot the n problem lies within the heater controls.
More than likely your heater core is plugged, and will need to be replaced
The Grand Cherokee is notorious for failures of the air flow control. However the Cherokee has the same basic problem. The blend door has a tendency to break, killing control over air flow through the heater core. The fix is fairly simple with the kit from HeaterTreater. Check the product at heatertreater.net.
Some things to check. Are the heater hoses warm? if not check for blockage at water pump, heater valve ( valve inline on the heater hose that allows flow to the core) or blocked core itself. If so then check the air mix door inside the cab under the passengers side to make sure it is allowing air flow through the core and blocking the ac and outside air. Radiator low, plugged heater core, door that closes outside air not closing, thermostat stuck open. That's about it.
Some things to check. Are the heater hoses warm? if not check for blockage at water pump, heater valve ( valve inline on the heater hose that allows flow to the core) or blocked core itself. If so then check the air mix door inside the cab under the passengers side to make sure it is allowing air flow through the core and blocking the ac and outside air. Low coolant, pluged heater core, feel the hoses to see if they are both warm, door closing outside air not closed. Cable or vacumn pot not closing it.