Hi,

Any thoughts appreciated on the issue with humidity and how to control it. I have a V90 which has had some repairs done on the A/C. My mechanic fixed a leak which was caused by a clogged drain tube for the A/C condensate. Seems that there was a blob of material (clay-like) that was the culprit. And the Volvo dealer replaced a recirculation diaphragm/bellows which was cracked. (It was still under warranty and thus replaced with no charge.)

The interior does seem to get humid too often. I need to either open the windows or use the A/C. I wonder if Volvos are humid due to being airtight or if there is a problem with some part of the A/C. Also, need to turn the A/C on now and then since there is a slight odor too. And the fan(s) seem to run for quite a long time after the car has been switched off. Sometimes for over an hour. I wonder if this is an indication of a problem.

Thanks

Hi (hope this gets to those who responded initially to my query),

This is an update. It took a while but I finally did get my car back to the shop. My mechanic did detect a coolant leak near the thermostat which he replaced. It's a lot better but there still is particular and unwanted smell. And the fan still stays on for a long time, about an hour, after the engine has been turned off. Sometimes the fan doesn't start until an half hour or more after the engine has been turned off. Probably takes some time for the humidity to be detected.

So any more suggestions would be welcomed. My mechanic did check the carpet again and it is confirmed as dry. I also did spray Lysol into the vents. And I try to use outside circulation more often over recirculation (except when passing by the diesels).

Thanks

"My mechanic fixed a leak which was caused by a clogged drain tube for the A/C condensate. Seems that there was a blob of material (clay-like) that was the culprit"

I had the same problem. Consecuently A/C was leaking the condensation water to the passenger footwell.

After removing the passenger seat and carpet there was ~1/4 gallon of water.

This is hard to detect, since the carpet seems to be dry, but there is water in the noise isolation layer. This is also causing excessive humidity in the cabin.

All the best

Markku

S90 60 kmiles ( had 144/80k 440/60k 940diesel/210k )

My mechanic removed the carpet and let it dry when he fixed the leak. I better double check to see if it is truly dry. Thanks for your help.

Regards, Mike

PS I'll post once I find out what the problem was. I'll be bringing my car to the mechanic in about a month or so.

I don't think my 960 is overly humid. One of the things that increases the humidity inside of the cabin is if the recirculation is left on. Is there any chance that your system is stuck on recirculate? I'd check that.

As far as the fan running after shutdown, are you speaking of the radiator fan? If so, that would seem to indicate a problem with running too hot, or with the temp sensor that controls the fan. I will say that my 960 started having the fan run after shut down, and it turned out that the thermostat was not operating correctly. Changed the thermostat, ended the fan running. That is the only time that the fan ran after shutdown.

If you are talking about the a/c fan running after shutdown, I don't know too much about this. I do seem to remember that in some models the a/c fan ran after shutdown to dry out the system. But I don't think it should be running that long. If this is the fan that you are talking about, it may be related to your humidity or odor problem.

Good luck, and let us know what you find out is the problem.

Mike

Per your suggestions:
1. I'll have the circulation switch checked.
2. I'm talking about the a/c fan running after shutdown. Even my mechanic thinks that the fan is running far too long after the engine has been shut off. It's probably running as it can and then probably cuts off since the max time has been exceeded. Thus the humidity problem doesn't clear up. But where is the moisture coming from? I think that the humidity may be due to the leak, as I indicated, that was fixed. Probably the interior never dried out completely.

I'll be seeing my mechanic in a month or so and have him check more into it. I'll let you know what he finds.

Thanks

My Volvos have never been too humid, except in our hot and humid summers here in TX. I question if your heater core is leaking or if your AC drain really is completely clean. Does the odor have a slight scent of antifreeze? Is the odor more musty? Believe this may help your diagnosis. If they were in replacing the vac motor, that is dangerously close to the heater core. Watch your coolant level in the engine compartment, and if it is going down, could be another clue.

Good luck,
dick

The odor is more musty. I don't think it is coolant. The coolant level is ok. I think your idea about the AC drain not being complete is the avenue to pursue. I'm going back to my mechanic and have him recheck the entire system. By the way, the dealer mentioned spraying Lysol in the ducts (which are located under the hood near the windshield) to get rid of the musty odor. I'll only try that after my mechanic has done the once twice over. I don't want to get rid of any symptoms for him in order to aid in troubleshooting.
Regards, Rivdog