I have a 1997 dodge ram 1500 the heater does not blow hot air but the inlet hose to the heater core is hot on the inlet and outlet side thermostat heats up to 200 degrees

have 2002 altima,blower works no heat at idle and very little heat when accelerating.I changed carbon cabin filter,made sure little gear under dash to temp knob wasnt broken,flushed and bled system.Nothing worked so checked hoses to heater core and found inlet hose was hot,outlet hose was not.So investigated this problem and came to conclusion heater core was clogged.An easy way to check is to get car to normal running temp. put on heater and blowers at full.Go under dash on passenger side where counsel meets firewall,this is where heater core core inlet and outlet aluminum tubbing go through firewall,you will be able to feel both tubes one closest to you is outlet, so if this one is not hot and and other is your heater core is clogged.I detached both inlet and outlet hoses to heater core from water control valve.Then I blasted water with waterhose and nozzle set at jet,first through outlet hose to blow gunk out,then through inlet hose until water runs clear.Reatach hoses fill and bled system.heater works great nice and hot!

THERE IS NO HEATER CONTROL VALVE ON THE WATER HOSES. NEW HEATER CORE. INLET LINE right before heater core hot, outlet after core look warm. Burped cooling system 5 times with engine at operating temp. Installed homade burp VALVE right after heater core outlet(high part of hose). Still no heat. Removed water pump, impeller still in good shape not stripped off shaft. Removed heater core hoses flushed water thrue the connections on the block to the water pump INLET and outlet. flushed water thrue heater core and hoses. Going to put it back togeter today. Used known good gauge to check water temp for operating temp in test. 195 f

check to see if both heater hoses are same temp when engine is at normal running temp if not heater core not flowing coolant may need to flush also make sure it does reach normal temp around 200

could be air in the system or the thermostat could be in up sidedown .

air door in heater box is stuck or door moter not working/HAYNES MANUAL.tim

Yes clogged heater core may be the answer in your case .

are heater inlet outlet mix valves standard for all dodge heater cores. I have 2001 dodge cummings blows warm air not hot when gauge is 195 degrees would there be a mix valve under the dash because it is not inline outside the wall

Hi
I would first check to see if both heater hoses are hot to the heater.
if 1 is hot and 1 is cold the heater control valve is closed or the heater core is plugged.

if the inlet and outlet hoses are getting hot to the heater core then the problem is the air temperture control blend door actuator in the heating/A/C ducts, this door directs air flow either across the heater core or the AC evaporator or mixes the 2 air flows for a desired temp at the outlets, hence the name blend door, to change this part u must remove the dash assembly.

it has a valve on the heater hoses on one hose that has a vacuum line running to it check both sides of the hose on each side of the valve if its hot both sides its ok. Then check to see if both hoses are hot this will mean that the water is flowing ok if its not reverse the hoses on the heater core somehow it will flush the core out. If this is all working then its the door on you heater box not closing the air conditioning hole off . It goes through the same vents as heater