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heater control valve

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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.
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.

Related questions

no heater

The lines to the firewall could be hot and yet the heater control valve (https://www.yourmechanic.com/services/heater-control-valve-replacement) 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...

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...

Car overheats when only in idle

Overheating at idle could be due to non functioning electric cooling fans. Other causes of overheating include trapped air in the cooling passageways, a faulty thermostat, a plugged radiator, collapsed hoses, and a faulty water pump or drive belt. Certain...

Hot air blows even though the heater is not on. I have a 2007 Jeep Commander

Your car has a heater control valve to control the flow of coolant through the heater core. It is controlled via engine vacuum so that in the case of a failure, it will default to the heat (open) position. Your...

Water hose leaking at firewall of 2012 ford focus

Typically, those are molded 5/8 inch ID rubber coolant hoses that are retained by either spring steel clamps or adjustable stainless steel worm drive clamps. Once you remove the hose, even to inspect it, it will not seal well when...

Heater not working properly

Common causes of no or inadequate cabin heat include malfunctioning blend door(s) (part of the in-dash ventilation network), a faulty or stuck heater control valve (https://www.yourmechanic.com/services/heater-control-valve-replacement), a plugged heater core, stuck open engine cooling thermostat, collapsed hoses, and low coolant...

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 (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-thermostat) - not likely in your case since the temp gauge...

Cars overheating but engine is cold and the heater blows cold air

Hello...the simplest option is to just request an engine overheating diagnostic (https://www.yourmechanic.com/services/car-is-overheating-inspection) 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...

Heater doesn't work

The heater control valve (https://www.yourmechanic.com/services/heater-control-valve-replacement) 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...

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...

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 (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...

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...

Hello. My heat will not come on. There is no leaks but my hose it hard as a rock. What could be the problem?

You need to feel both heater hoses coming from engine to heater core on firewall to see if they are hot? If not hot then engine thermostat is stuck open. If they are hot then you may have a bad...

how to bypass heater core in 2006 dodge caravan

In order to bypass a heater core you will need to disconnect both hose connections at the heater core on the engine firewall and then connect the two hose ends together using a bypass pipe and two hose clamps then...

I have a stutter when I am driving

The stutter, or vibration, could be due to an engine management (tuning) issue or is possibly caused by worn motor mounts that are allowing engine vibration to transfer to the body when the engine is under load. To evaluate the...

fan working but no heating

Common causes of no cabin heat include malfunctioning blend door(s) (part of the in-dash ventilation network), a faulty or stuck heater control valve (https://www.yourmechanic.com/services/heater-control-valve-replacement), a plugged heater core, collapsed hoses, and low coolant level. The cost to resolve the problem...

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...

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,...

Heater not working 2005 Acura TL

Hello - you may have a bad water pump (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-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...

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 (https://www.yourmechanic.com/article/symptoms-of-a-bad-or-failing-heater-control-valve) is not functioning properly, or the heater core itself is clogged enough to restrict flow. I would recommend a heater inspection (https://www.yourmechanic.com/services/heater-is-not-working-inspection) by a mobile, professional mechanic, such as one...

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