What to know about Coolant Vacuum Valve Switch:
During the winter, when a vehicle warms up and coolant starts flowing through the engine, it is not always flowing through the heater itself. The coolant begins flowing through the heater when the climate control knob is turned to the heater or defroster position. The climate control switch is generally attached to the vacuum hose which leads to the coolant vacuum valve switch.
When in the heater position, the coolant vacuum valve switch is opened and lets coolant from the engine to enter the heater unit, called the heater core. It is this warm coolant flowing off the engine into the heater core that gives off heat for the interior fan to blow through the vents. This is how heat works in many new vehicles.
SEE ALSO:HOW TO REPAIR CAR VACUUM PUMP
At times the coolant vacuum valve button can crack or become clogged with debris or old coolant. In these instances, the vehicle may experience signs similar to that of another cooling system issue so the correct analysis is vital.
Facts to Note:
The coolant vacuum valve button is used to control flow to the vehicle’s heater core. In the absence of this switch, a vehicle will have no heat in the winter.
How to Fix:
The Coolant Vacuum Valve Switch is confirmed that it needs to be changed. The coolant is lowered until it is below the switch.
The vacuum lines are disconnected and the faulty Coolant Vacuum Valve Switch is removed from the intake manifold.
The new Coolant Vacuum Valve Switch is fixed into the manifold and the vacuum lines are reconnected.
The coolant is refilled and bled of air. The Coolant Vacuum Valve Button is tested for operation.
The vehicle is tested to ensure proper operation of the Cooling System vacuum valve switch.
If you suspect the coolant vacuum valve button has failed, contact one of your trained technicians to have it checked. Routine maintenance is also essential for proper operation of the engine cooling system, which is where the heater unit obtains its heat.
Common symptoms indicating you may need to change Coolant Vacuum Valve Switch:
Cold air blows through vents no matter which position the climate control knob is in
Heat blows lukewarm
Coolant leaking, either underneath the vehicle or in the passenger compartment
Importance of this service:
While it may be easy to put off that coolant drip or wear an extra layer on the daily commute, if the heater isn’t correctly running, the vehicle occupants will be very uncomfortable. Furthermore, the vehicle’s defrost unit won’t function correctly, meaning that dangerous ice buildup could occur on the windows.