I would like to thank all the brickboarders who replied on my messages regarging T-stat and testing the temp gauge, now I won't freeze this winter.

Don't trust the "boiling thermostat in the kitchen" test until you use some more sophisticated measurement devices than your eyes. Optically good t-stat can open (sometimes partially) in lower temperatures than specified (92/87C). Just replace it, it's not expensive, neither aftermarket nor even genuine Volvo.

IF