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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
How much to flush out system cause car has no heat
The heater core being plugged is not the most common cause for this vehicle to not give heat out of the vents. If you move controls to heat and do not notice a temperature change when turned hotter the most...
Question
no heat in the cab
The heater control valve, that directs heated engine coolant to the heater core, may be stuck or otherwise non operational. There is also the possibility of a plugged heater core and/or a problem with the "blend door" in the in...
Question
Heater blows out cold air 2006 Nissan Xterra
Hello - the lack of heater function could have 5 causes: the engine is not getting up to correct temperature (center of the gauge) due to a malfunctioning thermostat, the heater control valve is not letting hot coolant into the...
Question
No heat in my 1995 Jeep Cherokee
Hello - to resolve your "no heat" issue, first check that the engine is running at design temperature (center of the gauge), or 190-205 degrees Farenheit. If engine is up to temp, grab the heater hoses (carefully) inside the passenger...
Question
Heat shuts off when idling n driving
The engine controls the heater control valve opening and closing as the engine is up to operating temperature. If the engine temperature is too low then the heater output will go cold or low heat output until the engine is...
Question
Very little heat from vents 2004 Mini Cooper
Hello - the lack of heater function could have 5 causes: the engine is not getting up to correct temperature (center of the gauge) due to a malfunctioning thermostat - not likely in your case since the temp gauge is...
Question
Truck is overheating and heater won't work
Hello. The symptoms you describe are commonly associated with air bubbles in the cooling system. If the cooling system was recently serviced then it may be possible that it needs to be properly bled of air bubbles. Air trapped in...
Question
Heater is not working. Replaced thermostat. Both hoses at firewall are cold. Maybe replace core? 2000 Ford F-250 5.4L
Hi - most likely, either the heater control valve is not functioning properly, or the heater core itself is clogged enough to restrict flow. I would recommend a heater inspection by a mobile, professional mechanic, such as one from YourMechanic,...
Question
Heater not working 2005 Acura TL
Hello - you may have a bad water pump and clogged radiator. When engine overheating occurs at low engine speeds, it indicates the engine is unable to transfer heat to the radiator and cool the engine. It would also result...
Question
no heater
The lines to the firewall could be hot and yet the heater control valve is not admitting the heated coolant to the heater core in the dash. So, you want to inspect that valve and make sure it is moving...
Question
Heater doesn't work
The heater control valve may not be opening fully and/or the heater core, beneath and within the dash, may be partially plugged. In both cases, the result would be inadequate heated engine coolant flow through the heater core and no...
Question
Heat not working
Plugging it in won't resolve the issue. Your vehicle has a conventional heater core through which hot engine coolant, from the internal combustion (IC) engine, circulates. If the no heat condition is occurring while the vehicle's IC engine is running,...
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
COOLANT LEAK 1978 Lincoln Continental Mark V
Hi - I believe you have a leak in the heater core - the tiny radiator under the dash (inside the big black plastic box you mention) that converts hot engine coolant to heat for the passengers. There is no...
Question
Changed thermostat now have no heat 2000 Chevrolet Silverado 1500
Hi - you are on the right track, there is likely an air pocket in your heater, preventing the heater from working properly. To bleed the heater core as well as the engine cooling system: fill engine with coolant, remove...
Question
My heater only blows cold air
Check the operation of the heater control valve, which is often located on the engine compartment firewall. If that valve doesn't move to the commanded position, or move fully, you will have a no heat condition. If the valve is...
Question
Cars overheating but engine is cold and the heater blows cold air
Hello...the simplest option is to just request an engine overheating diagnostic and the responding certified mechanic will identify the root cause(s) of the troubles you are writing in about and get the repair estimated for you. Repairs can be commenced...
Question
Heating problem
The first thing to confirm is whether or not the engine operating temperature is in the normal range and whether there is sufficient coolant in the radiator. If, for example, the engine cooling system thermostat is stuck open, and thus...
Question
Heater is blowing cold air 1999 Hyundai Elantra
Hi there. The blend door actuator is located toward the bottom of the HVAC box. It may be difficult to access, let alone replace. It looks like it may be located on the driver side of the box. One way...
Question
Heater fan seems to surge
Hello. Your vehicle does use a vacuum operated heater control valve to allow hot coolant into the vehicle's heater core so that warm air can be generated. If you hear an opening and closing sound then it may be possible...

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