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heater control valve

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How to Remove and Replace a Heater Control Valve
The heater valve is integral to a vehicle’s cooling system. Replacing one requires a new valve, some basic tools, and fresh coolant.
How to Replace a Heater Control Valve
Car heater control valves regulate the flow of coolant into the cabin. Heating and cooling issues result when the heater control valve fails.

Related questions

Question
What causes the heat to change over to cold when van is running? have had everything checked, all working 2005 Chrysler Town & Country
Hello - the first task is to verify that the engine is maintaining designed operating temperature so that you have a consistent heat source. This is easily verified by making sure the temperature gauge stays dead center. If it isn't,...
Question
Why is there water on my floor?
This may be related to your heater core failing. As you may know, the heater core is a radiator like component that circulates warm coolant through it that is then used to create the warm air you feel blowing inside...
Question
Vehicle heat wont get hot. what else can it be? 2001 Ford Expedition
Hello - your lack of heat from the heater is dependent of 2 things for it's source of heat: (1) a hot engine, and (2) hot coolant flow to the heater core (which you have replaced). If the engine temperature...
Question
New thermostat and truck is still blowing only warm air. It blows cold air when idling
Trapped air in the cooling system can sometimes account for this but you are indicating that you are getting heat, at times, which would indicate that coolant is flowing. There is a heater control valve and you want to make...
Question
No heat
This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater...
Question
Engine is overheating and heater does not work
As you may know, the heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you...
Question
Car overheating and heater blowing hot air.
The heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater...
Question
Heat control blows hot then cold air
This may be due to a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant...
Question
Heater is not working when I turn heat up and on.
This may be due to a clogged heater core. As you know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this warm coolant to...
Question
Heater only works on high. Heat is not hot.
If your heater only blows when the setting is on high, this may suggest that you have a faulty blower motor resistor. The highest speed setting may still work because in most cars in the highest fan speed settings the...
Question
Defroster and heater blows cold air while idling - 2005 Ford Escape
Hi there - the lack of heat from your HVAC system could be a couple of things: bad thermostat, heater control valve, or air in the cooling system. If the engine come up to proper temperature and stays there (i.e....
Question
Heater fan work's. After about. A half hour heat gets less. Fan still works. But no heat.
The lack of heat being generated by your system may indicate a faulty heater core. The [heater core]((https://www.yourmechanic.com/services/heater-is-not-working-inspection) is a small radiator like unit that circulates the hot coolant from the engine through the heater core which then uses this...
Question
Heating/cooling system blowing cold/warm air when it should be warm/hot air
This suggests you may have a clogged heater core. As you know, the heater core circulates warm coolant through it that is used to blow the warm air into the cab via the blower motor. The other possibility may be...
Question
Temperature spiking up after I changed my thermostat trying to get my heater to work.
The heater not working in some cases may be related to the overheating problem you are also having. This may be due to a faulty heater blower motor or potentially a bad heater core. As you know, the heater core...
Question
My oil light does not come on when the oil is low, and the heater only blows hot air for a short time.
When the oil pressure drops lower than 8 psi, then the oil light will come on. If the oil pressure drops and there is no light, then check the oil pressure sensor harness for power. If there is power, then...
Question
heat stopped working, only blowing cold air. checked and replaced fuses but no change
Two common causes of no heat, as you describe the circumstances, are a fault with the heater control valve and/or a problem with the blend door in the under dash ventilation system being stuck in position or inoperable. There are...
Question
Heater not working
This may be due to a faulty heater blower motor or potentially a bad heater core. As you may know, the heater core is a small radiator like unit that circulates the hot coolant from the engine through the heater...
Question
My heater seems to blow hotter when I'm driving versus when it's sitting at idle or at a stop light. Also the heater takes too long to heat up the cabin department. Why?
Hi there. When your vehicle is in motion and driving down the road, then engine coolant temperature tends to get hotter on the engine before it gets to the radiator, so the heater will naturally heat up more when driving...
Question
Heater is blowing but not hot. Repaired the hole in the radiator. Why doesn't heat up? 2008 BMW X5
Hello - there are several possible causes for a "no heater function". If the thermostat is not allowing the engine to heat up properly (center of the temp gauge), or there is lots of air still in the coolant system,...
Question
What's makes the temperature hand goes up then down?
If you are referring to the engine coolant temperature gauge on the instrument panel, unless the gauge is misreporting the temperature, a likely cause of too low of an engine temperature is a cooling system thermostat that is stuck in...

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