190E climate control

my 190E climate control seems to be in full heat, defroster mode regardless of function switch or temp comtrol setting. Any advice for diagnosis? Thanks.

Reply to
Mark30h
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vacuum hose disconnected from engine ?

Reply to
Bill

you have a vacuum leak somewhere. The default position for the vents is defrost heat. KH

Reply to
Kevin in San Diego

You have a vacuum leak, most likely the little U shaped hose that connects to the heater valve. The plastic screen between engine compartment and windshield needs to be lifted. The heater valve is further to the right, almost next to the battery, but you can't see it there cause it's covered by plastic, so lift the screen, you'll find the vacuum hose cracked. Martin. Autobahn Auto (757) 723-2112

Reply to
Bnzmn600

Any vacuum leak in the climate system will throw the system into full wide open heat, which is called "default position" that means heater valve wide open, vents open to defrost the windows, the only think you'll be able to control is the fan speed, but once you're driving down the raod, heat will sneak in, even if it's 110 F outside. BTW, if my assumption is correct, and depending on year 190 you have, the outer vents will blow hot air while the center vents are seat for AC..so try that. Martin. Autobahn Auto

Reply to
Bnzmn600

Thanks for the help. You were correct.Removing the screen below the windshield revealed the u-shaoed hose to the actuator cracked where it slips over the plastic hose. Under further inpection, I found a similar hose on the drivers side for the line from the engine to the actuator also cracked. 6" of hose and the heat/ac is fine. Thanks again.

Reply to
Mark30h

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