Hi,
Several weeks ago we had the T-stat changed as the heater just wasn`t putting all that much heat. It seemed to be marginally better but as it`s gotten cold again(-20) I noticed yesterday that the car again isn`t comfortably warm. It`s my wife`s car so I don`t drive it on a daily basis but compared to my 240 which CRANKS out the heat the 850 doesn`t even come close.
The temp guage is reading normal(& was with the old T-stat) so is there something else we should be looking at with this problem?
Thanks! Damn near freezing in Alberta!!
Rich

heater core and/or radiator may be plugged...try flushing when it weather warms up...

i personally think volvo uses special radiator antifreeze with special additives because our 1998s70glt puts out heat usually before the temp gage moves off zero...

or else they are using a special volvo radiator bypass that allows the engine to put out heat very quickly...personally i have never owned a car in the last 40yrs that heats up as quick as a volvo.

I trust you've shut off the cold air intake. I would also suggest looking at the recirc damper. (The earlier versions have a lever that breaks. The later ones have a lever that works loose.) See the Brickboard archives. I think you can get to it through the glovebox.

I also had this problem and replaced the thermostat although my temp gauge read low. Now the cabin warms up quickly, but after a while things grow tepid. I suspect the cabin temp sensor. If so, this will be sensor #4 (FOUR!).

-Punxsutawney Phil

Wow! -20 is a very cold input temperature if you're not using recirc mode. Which mode are you in? Is it possible that your recirc linkage in broken (common)?

Gerald C