How to show heat creeping up a wall *ideas needed*

Hey everyone.
im designing gas stoves and use blender for product renders and really simple spinning product animations that we can throw on the website to show what the product looks like. Now my boss wants a full blown animation that he can send out to all of our distributors to show how our product works.
The problem is i dont know the “best” way to achieve what hes after.

Basically the product we have stops your tv from being fried by the heat of a fire place if you put it above your fire.

my plan is to make a comparison animation that shows what happens without our product and then the difference our “cool wall” makes.

So i need to show this wall heating up.
the heat will move up from the fireplace over time and will need to be graduated, the further away the cooler it gets .
this gif shows an idea i had that was a flat plane with a gradient with the “heating up colours” that would animate up the wall to show the heat creep.
would love to know everyones thoughts and whether or not there i

s a better way of doing this task. all ideas are welcome. thanks very much

Try making a curved sine mesh, then press Alt+C to convert it to a Curve. Then add - - - - - - - line mesh or objects with gaps between. Select with shift+leftclick the Line objects and then the curve, press ctrl+p for curve deform and drag the lines on X axis, they should follow the sine… And i guess set up 2 objects in both ends of that sine with actuators for lines to trigger restrict view port to visible or press I, move the objects on x axis to adjust them in animation and press I for transparency on/off during the line objects moving on the sine to set transparency to appear in beginning as A and disappear on B - the end of the sine. Red color of the lines could represent heat and Blue - Cool. Maybe make red and blue to pulsate from darker to lighter or mix in emitter, or slightly increase the size and reduce it in few points during the object movement from a to b. Maybe this isn’t the best way to do this but it wouldn’t be bad. p.s I have never tried adding curve action, to another curve but i should try it.

You could make a simple gradient mask using the method I show below.

The shape, size and feather parameters can be animated using keyframes, and the output from the divide node can be used as a b/w mask or mix factor.