Need help.. Aircon C5 only cooling one side (not flaps problem)

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amigo
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Joined: 06 Aug 2020, 18:06

Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by amigo »

Hi

I got a problem with my c5 2007 .
The aircon is only blowing cold air the left side and not in right side.. The temperature at the right side is normal outside temp, the left is working perfect.. I have checked the flap , there is no problem on the flap in the right side that is rotation perfect and not brokenb and rotationto close the hot air works perfect, but there is no cold air in the right ac box side (its like the evap is not getting coog in that side?? ). I have checked the R134a and i get correct mesuments on low and high side.

Im totally lost.. Please if any know a way to fix it i will be very happy.
Last edited by amigo on 07 Aug 2020, 10:04, edited 1 time in total.

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GiveMeABreak
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by GiveMeABreak »

Do you have your VIN please, so we know exactly which Climate system you have.

amigo
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by amigo »

Vin: VF7**************[VIN obfuscated, can be read by forum staff]. 2 zone system..

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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by GiveMeABreak »

Ok, so Dual zone system. I can't quite understand the problem from your description - it's not very clear, but I'll try and explain the system:

You have 2 Air Distribution Motors (left and right)
You have 2 Air Mixer Motors (left and right)

Several possibilities:

If you are getting no change in temperature on one side it may be wither the air mixer stepper motor that has failed, or it is possible and quite common, for the plastic gear spindle to wear out that moves the flap.

That's another reason when testing the motors with Diagbox it can report the motors as working fine, and you can actually hear them turning - but if the plastic spindle has work out (plastic gears) or snapped off, it can't adjust the flap in the air mixer box.

Sometimes you can repair these by cutting a hole in the box carefully , retrieving the gear spindle and fixing it back into the stepper motor housing with a repair / glue / replacement spindle, then glue the plastic piece you cut out back in.

amigo
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by amigo »

I have already checked these flap motor and the flap (i have already been in there to check if that axle is broken, it was not broken and it works perfect) But that evapaporator is only getting cold on left side that is why i not get any cold air in the right side, but why and how can that happen?

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GiveMeABreak
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by GiveMeABreak »

Yes, but have you checked ALL these? There are distribution flaps AND mixer flaps for both sides. I can't see it being a problem with the evaporator as this is one unit in the box with the blown air being cooled overall - so you would be getting cool air coming through regardless - so it has to be your mixing motor or mixing flaps. How do you know if the spindle has not broken on the right? Have you opened the housing? The end of the gear may be turning operated by the motor - but if it's not attached to anything inside the housing then it won't be doing anything.

It is solely the air mixing and distribution flaps that will mix and distribute the air to the left or right. If you are getting cool / cold air on the left and not the right, then it has to be the mixing motor / gear/ spindle that is broken off inside the box. There's no separate left and right side in the evaporator - it is just one circuit flowing in and out.
C5 II Mix Flap.PNG
C5 II Mix Flap.PNG (129.95 KiB) Viewed 47 times
Number 6 is the mixing flap on the right hand side. If you take this off, you may very well still see and be able to turn the gear with a screwdriver, but what you won't see is that inside it may have broken along the shaft and therefore is not connected.

Look at theis video that shows the same system on the Peugeot - the same mixer motor. In the video you can see you have to cut it out to replace the brown flap unit complete with new spindle, then glue the piece back with a glue gun.


amigo
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by amigo »

Thanks for the reply

Yes i have been in there ... Just like in the video i have made that "cowboy" cut to explore the mixing flap becouse i think that was broken .... But i can see the flap is in perfect condition.. i have than manually turn the flap to close position on the hot air side.. but only outside air temp blowing around behind that closed flap and all the way out of the vents.. But ice cold in the left side... I think there must be a problem in the evaporator , but dont know..

Really anoing problem..

Sorry my english btw

amigo
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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by amigo »

"There's no separate left and right side in the evaporator"

I know that but the R134a is entering in the left side of the evap and that is the working side, thats why i think its maybe not going all the way to the right before it returns in the evap? ... Becouse if i send hot air in the left side than u get a little more cold air in the right side? :S

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Re: Need help.. Aircon C5 only cooling one side (not flaps problem)

Post by GiveMeABreak »

Ok, got you - so eliminating that, you've either got a leak or a block in the evaporator core somewhere that's not allowing the liquid refrigerant to pass through the entire core. It looks like it's only getting through half way round the evaporator before it reverts back to vapour / liquid on it's way back to the condenser, so the air on the right side of the box is not getting cooled as there's no cold refrigerant getting sufficiently through over that part of the evaporator.

At this point I don't know what your best bet is - as they don't list the part separately - just the complete heater unit and that of course is a dash off job to get to it.

I don't know if it might be worth getting a full A/C system clean - where they vacuum and recover everything out, clean it and refill it again. Takes a few hours top do, but I'm not sure what else to suggest.