2005 Town & Chrysler heat is not working properly

If you checked properly and coolant/rad isn't getting hot, coolant is up to proper level, then I'd replace thermostat.

means the thermostat went bad from just water they need anti freeze to keep it from rusting and working properly also when you add water when its cold next time run the engine so it goes threw the block also squeeze the the upper radiator hose to get all the air out sounds like you have a air lock

My 2008 had the same problem. It turns out that the coolant system, if not filled properly will cause air to block the transfer heat in the heater core. This is what I did, and it worked, while your motor is cold, pop open the caps on your radiator and your overflow. Top off your radiator to the brim with antifreeze, put caps back on. Start and bring up to operating temp, (I just drove to the grocery store). This will work any vapor bubbles trapped to get flushed out, and then repeat. This can take 2 or 3 times. Easy fix.

Is the radiator fan still coming on ? Is the compressor running ?

Has anyone tested the new temp unit to make sure it's functioning properly? Or is their possibly a mechanical thermostat in it that's hung and needs to be replaced?

Regular prestone will do the trick

I have seen these cars have a lot of problems with the cooling fans. even though they may work, they may not be spinning fast enough. the other problem is the collant temp sensor. make sure you are burping all the air out of the vehicle before toghtening radiator cap or resevior cap

If the coolant level (antifreeze) level is low there may not be enough fluid in the system for the temperature sensor to register a proper reading ( think of it as holding an oral thermometer just outside of your mouth).

Insufficient fluid passing through the heater core (small fan that blows through a small heated radiator) may not be enough to produce heat.

However: At increased speeds the engine may be heating what little fluid there is to a point to supply heat to the heater core, and register on the temperature sensor.

The fan is computer controlled and will not come on untill it reaches 212Deg . It should come on though if you turn on the air conditioning, if not you could have a bad fan relay or relay plug.

did u check all the hoses? it might have gotten so hot that u blew a bigger hose