My van gets hot but doesn't loose coolant fluid What could the problem be?

From the reserve tank, one hose should go to the radiator and the other should be for overflow. Sometimes that one goes to an accumulator, sometimes its left dangling cause its just there to drain any excess fluid from expansion in a hot system. Depends on the vehicle. If its in an enclosed system or plugged you would get an excess of back pressure which would further heat up the coolant and inhibit flow. Just leave it there. If it pukes coolant when hot then its doing its job. Don't overflow your reserve tank.

Check your coolant level before you start your car if full cold and when in idle you can go on to the next thing to check, possible plugged heater core.
With van engine cold remove heater hoses from firewall carefully so you don't loose too much fluid out the hose. Now get a garden hose and run water back and forth through the heater core inlet and exit, watch for discoloration and possible debris, you want to see a good water flow here.
Replace heater hoses, clamps, and any lost fluid. start and warm as you would normally.
How many miles are on your Sedona?
Next thing on your list could be your thermostat needs replaced.
If this hasn't resolved your problem you will move on to the water pump.
Also check your coolant tank! It may look good from the outside but pull the cap off and make sure the little return hose is attached to the cap, add a small hose clamp if necessary. The hose on my 02 Sedona got so hot it swelled up and fell off leaving no way for the engine to replenish the vital coolant when the engine cooled down. THIS $1.00 FIX CAN SAVE YOUR ENGINE!!!

Good luck

check the water pump and the heater core

need to presurice the system to see the leak

Any chance you got an air bubble in the system? Try loosing the return hose from the heater and make sure your getting fluid through the heater core.

I can answer some of your questions without being there in person.
The smell inside the van is from fresh air entering the venting system. Not sure why you don't get it from all vents. The fresh air intake is in front of the windshield and will pick up any smells from the engine compartment.
Loosing the serpentine belt would not necessarily cause you to loose ps fluid, but having a leak could drain the pump and damage the bearings in the pump, causing the pump pulley to drag on the belt.
The ps pump could be in the final stage of failing.
And the shaft seal in the pump could be leaking fluid onto the engine and exhaust.

If you are not seeing fluid spots on the ground chances are you have an head gasket problem

get the antifreeze that mixes with any color you should be fine also make sure you bleed the system get the air out of the cooling system there should be a petcock to bleed it with,crank let get operating temp.open petcock till steady stream runs out close pc your done.

The line to the reserve tank to the radiator could be plugged up or you have a loose radiator cap or a bad seal causing the tank to hold whats in it. The coolant system is a pressurized system and if a seal is bad or a line is plugged you will experience this problem for the pressure is not there to take whats needed from the tank to deploy in the coolant system

The hoses to the heater core may have been re-plumbed to by-pass the heater core (a temporary fix to a leaking heater core)...so verify that hoses are routed properly. If they are, check coolant fluid level....when it is gone...the heater will not blow hot, and you will likely burn up the engine (if coolant is gone...temp gage may not register "hot" because there is not fluid for the temp sensor to measure. Also...you may have a broken/cracked vacuum line (the valves for switching where the air gets directed are typically vacuum controlled) Hope this helps.