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Old 12-20-2004, 02:46 AM   #1
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alright, so I know my a/c unit has a leak, how you ask? well i had a local shop fill it up in july with freon and uv stuff to see if there is a leak later and about a month ago i get a warning from my ecc saying low freon, so I got a leak, great. I'm not concerned at the moment (gonna have the shop look at it this week or next to see how much to fix it, it has already been converted to r134a thanks to the previous owner who just forgot to mention a leak in the system ) but I do have one question. I've had the system on econ now for a month since I didn't want to run the a/c unit with low freon/oil because i was afraid I'd burn up the system. Am I correct? Also, is it alright to run the system on auto ( in hopes of just heat, no freon usage ) and get some heat out of the vents? Right not now the econ doesn't do crap and while I dont particularlly mind, some heat is always nice. What do you think guys?

Dave
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Old 12-20-2004, 10:36 PM   #2
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Old 12-20-2004, 11:27 PM   #3
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The HVAC system has two switches, one for low refrigerant and the other for hi pressure cut-out. If you had no freon at all in the sysyem, the compressor would not turn on no matter what setting you had it on. That is the compressor'* way of preserving itself.
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Old 12-21-2004, 12:06 AM   #4
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huh, so even if I have the heat on, it still uses freon? And no matter what setting, econ or auto, it'* alright to run the system with low freon? (getting fix wednesday) Thanks in advanced

Dave
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Old 12-21-2004, 02:53 AM   #5
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econ doesnt turn the compressor thats why it is call econ to conserve gas, all others you the compressor like auto and defrost
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Old 12-21-2004, 03:01 AM   #6
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Quote:
Originally Posted by CrazyDaveFYM
huh, so even if I have the heat on, it still uses freon? And no matter what setting, econ or auto, it'* alright to run the system with low freon? (getting fix wednesday) Thanks in advanced

Dave
Yeah....The defroster uses the freon to dry out the heat when defrosting instead of making a humid mess of the windshield in the winter.
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Old 12-21-2004, 01:12 PM   #7
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I don't think that'* true. I have my compressor unplugged because the clutch is going on it. My heat and defrost work just like they used to.
My money is on your condensor or evaporator core leaking the freon.
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Old 12-21-2004, 01:35 PM   #8
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The defrost and auto settings uses a closed system so no outside moisture is introduced. It recirculates the air. On econ setting, outside air is introduced. If your compressor is broken, missing, low on freon or otherwise you will still have heated air but the compressor will not kick on. Like Lakeville said, it removes the humidity from the air so potentially it could cause the windshield for fog up quite a bit.

The two switches make the system fail-safe to prevent damage to the compressor.
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Old 12-21-2004, 01:55 PM   #9
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ECON is basically an A/C compressor bypass switch. It should operate the same a auto without the compressor. Running it low will just reduce cooling capacity. Defrost mode always enables the compressor to dry out windshield condensation as previously mentioned. When it gets too low it will disable itself also as previously mentioned.

Glorkar,
The clutch is independent of the A/C system. It will engage when it is told to whether it is bad or not. With it unpluged, you are getting heated air to the windshield in defrost mode but not dehumidified air as the system was intended.
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Old 12-21-2004, 02:07 PM   #10
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Quote:
Originally Posted by Ranger
ECON is basically an A/C compressor bypass switch. It should operate the same a auto without the compressor. Running it low will just reduce cooling capacity. Defrost mode always enables the compressor to dry out windshield condensation as previously mentioned. When it gets too low it will disable itself also as previously mentioned.

Glorkar,
The clutch is independent of the A/C system. It will engage when it is told to whether it is bad or not. With it unpluged, you are getting heated air to the windshield in defrost mode but not dehumidified air as the system was intended.
when the system is low on freon the clutch wont kick on and on the auto setting the compressor shoudl kick on
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