I was reading the build sheet on my new 2016 F350 Diesel.
As a option it has "PCT Supplement Heater" , anyone know what that is?

 

yes, It is aux heater that is similar to a space heater. It is a heating element in the heater box that helps warm the cab prior to the engine reaching operating temperature.

Only available on the diesels and most areas has to be added as an option during ordering.

See page 14 in your Diesel owner's supplement manual.

 

Thanks Ill have to read up on it , cab doesn't seem to get very warm very fast.

 

I found that of I set the controls to the highest heat, and the turn the air to the vents, I will get warm air almost immediately.

 

Turn your **** all the way to "HI" and hit the recirculating button on the right side of the Heat/ AC control panel. Don't turn the fan up too much, maybe 2nd or 3rd setting and you should start feeling warm air in about 15/20 seconds depending on how cold it is. Took me a while to figure it out also.

 

I won't help a lot but it does start putting out luke warm air almost immediately.


It (for me) works very good at directing warm air to the drivers seat pretty quickly.

 

It also has to be cold enough out for the rapid supplemental heater to turn on. There is some "Ford Math" involved in the decision making process as to whether it turns on or not. It vaguely describes this process in the owners manual, but something like +25F or lower outside and/or a certain number of degrees inside temp vs. HVAC desired temp settings. This why "HI" is a good setting when you want to have the greatest odds of it coming on. It does work well... Only took going for a ride in a truck without it to realize just how well it works.

That recirc button being ON, meaning don't bring in outside cold air is important. Unfortunately, if you use the defrost setting on the HVAC you can't turn that button on. So I end up putting the HVAC in manual mode and have it blow hot air through the defrost vents and in my case the footwell too. However, this doesn't do a good job of keeping the inside windows from fogging up, so for me I end up switching off between the two. The defrost setting also defaults to the highest fan speed setting known to man.

When it's 0F out or colder, and you've just started it, don't expect 90F air to be coming out of the vents even with that supplemental heater. Also, driving it as soon as practical helps the warm up. As idling only gets you so much.

Doczenith - a Forum member here, did a spreadsheet on what the rapid supplemental heater does. Kudos to him for freezing as he had to do overnight cold soaks and then in the morning pull the fuse to the heater to measure the differences. And it does make a difference.

Just my .02.