97 Ranger 2.3L RWD Heater Control Valve?

[jockodog]

Is it possible my '97 Ranger 2.3L RWD doesn't have a heater control valve? It could have been removed. Are some 97
2.3 Rangers designed without heater control valves?

 

[sgtsandman]

Not that I've ever seen. Rangers without A/C, yep. Without heat, nope.

 

[jockodog]

Not that I've ever seen. Rangers without A/C, yep. Without heat, nope.

 

[jockodog]

I have read in other forums, that on some Rangers, the blend door is the only control of heat....dash knob controls all cold or all heat or a mixture.

 

[jockodog]

It is possible a previous owner removed the control valve entirely from the heater core inlet/outlet hoses, but I cannot find any loose vacuum line that would've been connected to it.

 

[sgtsandman]

All my Rangers have been newer that 1997. So I can't say you are right or wrong on that. Everything I've had, had a valve to control the flow of coolant to the heater core. It seems to me depending on a blend door to do that job, while possible, wouldn't be the best choice. But hey, they do it on other things like piston driven aircraft. So, it's not improbable.

It could have been cable controlled. Is there a random cable running into the engine bay?

 

[jockodog]

All HVAC controls are dial-operated and by vacuum. It is my understanding that the MAX-AC dial position would do two things...move the outside air door to closed (recirculate) and also close the heater control valve to stop coolant flow to core.
Thanks for you input.

 

[RonD]

Ford Rangers never used a "heat control" valve in the engine bay
1983 to 1994 they use a cable operated Blend door, slider on dash for cold---hot
In 1995-2011 they used an electric motor blend door<<< these often failed

Blend Door directs the air from the blower/fan, its behind glove box to the left inside the air plenum(box)
In COLD setting the blend door directs all air around the heater core
In HOT setting all air goes thru the heater core
And you can adjust it anywhere in between to "blend" the hot or cold air to the temp you want

Ford did add a Heater BY-PASS Valve in Ranger engine bays for use with AC
This shuts off flow thru heater core so cab air box stays cooler
It doesn't "adjust temp" its an on/off valve, vacuum operated from Cab climate controls

This by-pass valve is not needed and can be removed without effecting heater or engine operation
It could effect Maximum cooling for AC in cab as the heater core would still be hot but if blend door is working then no air would pass thru it so it would only change cab temp by a few degrees

 

[jockodog]

Ford Rangers never used a "heat control" valve in the engine bay
1983 to 1994 they use a cable operated Blend door, slider on dash for cold---hot
In 1995-2011 they used an electric motor blend door<<< these often failed

Blend Door directs the air from the blower/fan, its behind glove box to the left inside the air plenum(box)
In COLD setting the blend door directs all air around the heater core
In HOT setting all air goes thru the heater core
And you can adjust it anywhere in between to "blend" the hot or cold air to the temp you want

Ford did add a Heater BY-PASS Valve in Ranger engine bays for use with AC
This shuts off flow thru heater core so cab air box stays cooler
It doesn't "adjust temp" its an on/off valve, vacuum operated from Cab climate controls

This by-pass valve is not needed and can be removed without effecting heater or engine operation
It could effect Maximum cooling for AC in cab as the heater core would still be hot but if blend door is working then no air would pass thru it so it would only change cab temp by a few degrees

 

[jockodog]

Thanks for that info. I am in the process of replacing all AC components due to a chronic leak which has not been found, so I will to reinstall the control valve and its vacuum line.
That would be coming from the dash the back of the dash controls, right?
MAX-AC is a virtual necessity in the Summer here.

 

[jockodog]

Ford Rangers never used a "heat control" valve in the engine bay
1983 to 1994 they use a cable operated Blend door, slider on dash for cold---hot
In 1995-2011 they used an electric motor blend door<<< these often failed

Blend Door directs the air from the blower/fan, its behind glove box to the left inside the air plenum(box)
In COLD setting the blend door directs all air around the heater core
In HOT setting all air goes thru the heater core
And you can adjust it anywhere in between to "blend" the hot or cold air to the temp you want

Ford did add a Heater BY-PASS Valve in Ranger engine bays for use with AC
This shuts off flow thru heater core so cab air box stays cooler
It doesn't "adjust temp" its an on/off valve, vacuum operated from Cab climate controls

This by-pass valve is not needed and can be removed without effecting heater or engine operation
It could effect Maximum cooling for AC in cab as the heater core would still be hot but if blend door is working then no air would pass thru it so it would only change cab temp by a few degrees

 

[jockodog]

I already know my blend door and/or motor needs to be replaced. I have both already. Except for the engine, there was a lot of deferred maintenance.

 

[RonD]

There are 2 hard plastic vacuum lines that come out of the firewall on passenger side next to Blower/fan box in engine bay
They look like electrical wires
A black one, which is the Vacuum source for climate control Vent directions, i.e. defrost, panel, floor, it goes to the Vacuum reservoir, a black "ball" located down low at front of engine bay passenger side, often have to lay down under front bumper to see it
This line often gets brittle or melted from exhaust manifold/pipe heat, if you only have defrost in the cab this vacuum line is the problem

The 2nd vacuum line is GREY hard plastic, it goes to the By-pass Valve on heater hoses
It only has vacuum when Selector switch in cab is on OFF or MAX AC setting

 

[jockodog]

There are 2 hard plastic vacuum lines that come out of the firewall on passenger side next to Blower/fan box in engine bay
They look like electrical wires
A black one, which is the Vacuum source for climate control Vent directions, i.e. defrost, panel, floor, it goes to the Vacuum reservoir, a black "ball" located down low at front of engine bay passenger side, often have to lay down under front bumper to see it
This line often gets brittle or melted from exhaust manifold/pipe heat, if you only have defrost in the cab this vacuum line is the problem

The 2nd vacuum line is GREY hard plastic, it goes to the By-pass Valve on heater hoses
It only has vacuum when Selector switch in cab is on OFF or MAX AC setting

 

[jockodog]

That is very helpful info. Thanks. Much appreciated.