Fan Speed And Air Flow

[Oka]

Brown Volvo 2001 XC70
Normally, I set the fan on the third or the fourth green LED
for 'good' temperature and 'enough' air flow.

Red Volvo 2001 XC70
- At the third or fourth green LED, the noise at the heat core is as louder
than the brown Volvo at full blast.
- At full blast, the air flow is as low as the brown Volvo at second LED.

So it looks like the red Volvo is working much harder to produce air flow and temperature.

[jimmy57]

Have you looked at the air filter for the a/c-heat system? (usually referred to as the cabin filter)

[oragex]

Also, there may be a flap door that doesn't open properly- broken hinge, burnt motor or simply a CCM calibration

[abscate]

There are also two different air filters for the P2 cars, thick and thin.

The ECC control unit will give different flows depending on how it is programmed, too.

Jim commented here when I replaced my filter

viewtopic.php?f=9&t=70538&hilit=2005+ca ... 0&start=10

[Oka]

The gotcha here is the word 'filter'. Then it clicked it did not come to mind.
Started driving the care a few months ago. Very logical to think about my issues could be a result of the "working much harder" scenario to relate to the filter. As soon as I could, I went to the car just to take a pick underneath the glove compartment. Was shocked! First, the panel underneath the filter housing was missing. Found the panel inside the box the previous owner had given me.

Looking closer, I found the filter housing cover was half way opened I could see the filter. I supposed to have four screws. The first two were completely missing. The other two further back has the left one almost half way out; the obvious reason I mentioned "the noise at the heater core is louder . . .".

There are more. The filter housing has two compartments. Shouldn't the filter be in the first compartment, the one closest to you? This filter was in the further compartment. When I removed it, saw lots of debris clogging the filter. Dirt was literally falling out of the compartment while I was trying to pull it out. I managed to remove it, vacuumed the compartment, put the cover back just to test it. Wow, at the second/third LED fan speed setting, the air was just gushing through the dash vents, of course without a filter.

Really appreciate everyone's input on some possibilities.

[abscate]

The two slots are explained inthe thread above...P2s have a choice of filter