Poor A/C in rear of car

[maverick54]

HI guys first post and hoping someone can offer me some advice please.

Recently topped up my air con with a DIY top up kit and am getting about 6-7 degrees coming from the front vents during hot weather.

The problem I have is that my rear seat passengers are complaining that they cannot feel the air con in the back of the car, and it's better with the windows open.

I have checked the rear vents and the air con does have a very poor flow rate to the rear of the car. Anyone have any ideas what may be causing this please?

I did swap the cabin filter a year ago and have only covered 6000 miles since

[JohnHere]

Kindly let us know the year, make, model, and engine size of the vehicle in question and whether it has rear A/C or whether the air is just ducted from the front.

[tbirdtbird]

6°C equals about 43° F. That is a very decent vent temperature. Be careful with topping off, it is better to weigh in the refrigerant, and some cans contain sealer, read the label. We do not advise using sealer ever.

Is this problem new?

[maverick54]

Kindly let us know the year, make, model, and engine size of the vehicle in question and whether it has rear A/C or whether the air is just ducted from the front.

Hi, thanks for the reply. it's a Citroen C4 Grand Picasso 2016 1.6 bluehdi

The aircon is just ducted from the front.

[maverick54]

6°C equals about 43° F. That is a very decent vent temperature. Be careful with topping off, it is better to weigh in the refrigerant, and some cans contain sealer, read the label. We do not advise using sealer ever.

Is this problem new?

I've owned the car for 2.5 yrs now and the air con has always been poor in the back of the vehicle. I topped it up 2 years ago not long after I bought the car. Both times I have used the same product. (Shown Below)

https://www.halfords.com/motoring/engin ... 12110.html

[tbirdtbird]

image.png (216.08 KiB) Viewed 2502 times

I would be leary of that product. It states it has an additive package, but does not specify what that is. Sealers are to be avoided.
Perhaps the labeling on the back side explains in more detail, if you could get a close-up of the can you used.
I am not able to bring that product up on any USA sites or even on Google
I have blown the image up slightly

[maverick54]

I do not have the bottle now. There was £10 cash back on it and as it took the whole bottle to top up the air con I took the empty bottle back for the refund.

Pretty sure they contain the coolant and oil to top up.

[tbirdtbird]

Any way to go back to that store and take a pic of the ingredients...closeup...

[JohnHere]

I do not have the bottle now. There was £10 cash back on it and as it took the whole bottle to top up the air con I took the empty bottle back for the refund. Pretty sure they contain the coolant and oil to top up.

There was no way to know whether the system needed any refrigerant and oil at all, and it's virtually impossible to "top up" a system to the proper amount. We don't know the operating pressures, but it could be grossly overcharged now since you installed the entire can of product. But that's only a guess. A certain procedure must be followed to correctly re-charge a system as another consultant alluded to above. Unfortunately, those "death kits" as they're known in the trade don't allow consumers to do so. Many professionals believe that those kits should be taken off the market.

That said, it sounds from your first post like this is an airflow problem rather than a refrigeration-system issue—with possibly even some re-heating going on (heated air mixing with the refrigerated air). I don't have any technical information for your car, so I don't know whether it has blend-door motors or whether levers and cables control the air and air temperature directed to the back. Have you looked into those possibilities?