Temperature ventilation cold on passenger side in winther

Hey,

On winter, when I put the ventilation a hot temps, we are alomost freezing on passenger side witch is not the case on driver side.

I check the AC, and everything seems to be alright

Is any one have an Idea ? I spoke with a subaru mechanic and he told me that might be the heater core.... I replace the coolant as he suggest me but no result....

is anyone can help me ?

the heater core gets plugged up mainly on the bottom part which is responsible for the passenger side.

some have had success by disconnecting the hoses to the core, then flushing the core out backwards & forwards several times. then reconnect your hoses in the opposite way that they were. fill it back up and hope for the best.

it's worth a try since it's much cheaper and easier then replacing the core.

Tks for the answer !

I guess I will have to try that...

I read the suby manual and to get access the heater core, we need discharge refrigerant.... Is the any way we can not touch this circuit, if I proceed to change the heater core ? I don't have the compressor for th AC

tks

wasn't the reverse-the-hoses idea yours to begin with frank_ster? still working ok? (although running heat in july isn't too common)

not unless you live in canada

mine is much better but not as good as it should be when -25deg c outside the passengerside is warm not hot.

i have two one with dual a/c and the regular in my 2.5i. and i cant remember witch had this problem. or if both did.

to determine if the the heater core is blocked put on full heat.

turn off fan for coupple min with the car running then turn the fan on you should have heat both sides but then the passengersde will get gradually cooler. this is because the core is aluminum and the heat will transfer across to the entire surface. but when the air is passing through it cant transfer enough from other parts of the core hence your problem.

if you have dual zone a/c the passenger side door could be simply stuck.

if the door is stuck the above test will result cold air out of the passenger side vents immediately

I flush the core out backwards & forwards several times, no result... Put the heat on and 70 celcius on driver side compare to 38 on passenger side. And today it about 29 celcius...

I didn't see that much dirt coming out from the core... Is it ok if I use CLR to clean the rest ? I trush more CLR then putting air pressure ...

Could it be possible there is some door stuck somewhere ? as Frank_ster say's ... I tries to turn off the fan and It did exactly as mention above, heat gradually cool down. Does it means that the core is 50 % block ?

I looked at the shema, and I can't understand why temps is not the same each side...

By the way, what is a dual zone a/c ? sorry not much a mechanic pro !

^ dual zone is where you have temperature settings for drivers side and passenger side.

and typically has a "auto" button

but if the temperature went down gradually your heatercore is blocked.

try clr why not if it doesnt work you need to change it anyways

Got it !!!

After CLR, air pressure, 1h30 min of backward & foward flushing... Dirt cam out mostly after CLR.

90 celcius on driver side and about 80 on passenger side! Not perfect but enought for me !! I never thought that would work that great... Can't wait to see the result this winter !!!

Tks guys !