I have a very old dimmer that I would like to replace as it doesn’t work.  It is in the same box as another switch that controls a different light.  The dimmer used to control a fan but we replaced the fan with only a light.  The dimmer is the only switch that controls the new light.  The dimmer only has two red wires.   If it is a single pole why would there be two red wires? One red connects to a hot attached to the other switch in the box.   If I buy a new single pole how should it be hooked up?  Thanks
	
		
			
		
		
	
				
			 
				
