First, make sure the engine thermostat is working. Do this by starting a cold engine and holding the top radiator hose. It should be cold, As the engine heats up, the thermostat will "open" and the hose will become hot, as the water is allowed to enter the radiator.
Knowing you have hot engine water, find the fitting/hose at the rear of the engine, near the firewall. This is the hot water that waits to enter into your heater core, from the engine's manifold.
Next to this hose that disappears into the firewall, will be a second hose that exits and runs back to the side tank on the top of the radiator. This is the return hose from the heater core.
With the heat selector in "off", the return hose will be cool or cold. Selected to "Hot", the water will pass through the "now open" heater valve, through the core and back to the radiator. This makes that return hose warm/hot.
Turning the selector back to cool will close the valve, and the return hose will cool.
This is a non invasive method to check the valves ability to open & close IF the selector and it's control lines are working.
The valve may not be receiving instructions from the selector. Another problem entirely.
Where is the heater control valve on a 1994 Buick Regal
Put a potato in the exhaust pipe.
bs
where is the heater control valve on a 1994 2500 suburban
Ok, I got the answer to this question. It seems that there is not a heater control valve in the heater hose line.
The Chrysler Concorde does not have a heater control valve. The temp is regulated with a blend air door inside the dash.
On my 1994 Corsa you pull the fan control knob to switch on the rear window heater.
On a 1994 E-150 van, the heater control valve is typically located near the firewall, on the passenger side of the engine compartment. It is connected to the heater hoses that run from the engine to the heater core. You may need to remove some components or panels for better access, as it can be somewhat hidden behind the engine or other parts. Always refer to the vehicle’s service manual for specific guidance on locating and servicing the heater control valve.
you are
What is the stock size tire for a 1994 sierra Z71
it is in the heater hose close to the firewall near the master cylinder its a black plastic valve with a vacum hose connected to it
yes it will