I have an '05 Ram and am seeing a heat rise, as expected, when warming up the truck in these colder temps. However, no heat is coming from any vents when the fan is on. Only when I step on the accelerator and/or begin to drive, do I get a distribution of heat from the vents. Any suggestions?

 

Check your cooling system fluid level... If it's up? check your cooling system circulation, could be a failing water pump.
Then I would replace your thermostat. could be stuck closed and not allowing circulation to enter the cab

 

I did have a temperature spike a few months back and all seemed fine since then. Maybe that could have been the start of the failing water pump as you mentioned. I have checked the fluid level and it is full. I will also look in to the thermostat issue as you have mentioned. Thanks.

 

this is a symptom of low coolant levels or air in the cooling system.

 

If there is air in the system, can I do something to eliminate it or is that a project for my mechanic? Upon the first temperature spike, my mechanic did say that it could have possibly been an "air binding" reaction.

 

cooling systems for modern vehicles should be vacuum filled using an air-lift filling tool. Manual filling is a slow process that can require multiple thermocycles to get all the trapped air out. have the system vacuum filled... ensure the system isn't leaking first. I see this problem on just about every chevy uplander that comes into the shop.

 

Make sure your freon levels are at the right amount. Too high or too low can make your A/C run inefficiently. Also, I'd check and make sure all the proper caps and hoses are hooked to your A/C pump.

 

Not to discrete what you just said ramthedaughterdodgethefather but he still should be getting heat even if the AC is broken, failing or even missing parts.

True you should keep you AC fulling charged and all the access points, covered