Volvo: water under passenger seat, driven device, heater core

Question
QUESTION: I am losing water daily, there is water under the passenger seat and the carpet is soaking wet. Also there is steam coming out of the vents if I put the heating on.

ANSWER: Sarah,
Most likely the heater core is leaking. Check under the dash around the heater box for signs.

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QUESTION: I've changed the heater core and that solved the problem of the steam coming out of the vents and a wet windscreen.Thankyou. However I still have to fill up the car with water everyday with about 2 pints of water which seems to be ending up in the rear passenger footwells as the carpets are still being soaked. Any ideas?

Answer
Sarah,
The only link from the cooling system in your car to the interior is the heater core. Since that is repaired I don't know what or where this coolant is coming from. Have the cooling system pressure tested and watch for leaks. Could someone have installed some sort of a cooling system driven device to the rear of your car? Search this out, trace as to what is leaking while under pressure.