Hello folks,

Heater hasn't worked in the almost two years I've had the car, so let me show you the symptoms.

-AC works
-Fans work
-Cold air blows just fine; though, will note that that there's a weird noise when I start up the fans or AC (sounds like air faintly whistling through the system, goes away after about five seconds)
-No heater core leaks that I know of (no residue appears on windshield when defogger is on, and no leaking that I can see or smell)
-Car runs 15 degrees Celsius under normal temp, but just recently replaced water pump and thermostat with OEM (temperature has been the same before and after swap)

Just recently, I attempted to unclog the heater core. Both hoses felt pretty warm, but the inlet DID feel warmer, so I ran compressed air through the system backwards. Proceeded to run CLR and hot water through a pump for about five minutes. Then I ran hot water again for two more cycles, and finally did one more with cold water. Finally, I blew it away one last time with air. The system broke free a significant amount of debris, and the water flowed perfectly and strong.

I burped the system after putting everything back together, and drove an hour home. Gave it a good few pulls on the way home (revved up to 5000 a few times for a good ten seconds plus).

Still no heat!

So what could this be? I'm thinking that perhaps the mechanism that releases the hot air in the HVAC could be stuck, but that's my last resort. Any insight or questions is greatly appreciated!

Thanks for reading my long winded diagnosis.

 

bump , it's cold as dick