2002 Volvo VNL Problem

Hey guys,

I just got off the phone with a driver of my 2002 Volvo N-14 engine(430hp) small engine, with a 10speed. We the driver left on the 5th and didnt get to far, he left Waterford Mi at 9am and called me at 6pm the same day to tell me he has no heat in the truck. He took it to a TA and they said it needs to go o the dealer but he had a load and had to get to Jackson Wy, by 7am saturday morning. so he got two portable heaters and left the TA. Today I just got a call and he told me that the coolant on the truck is flying by. he said on saturday he put 1.75 gallons and today he had to put in another .5 off a gallon. So the truck is coming back by the 18th of the month, so eight more days... so ill have my guy take the heat apart and fix it and see if that does it or not. the heater core of the truck is fine, both of them are perfect. I need help!

 

Please help, what could be the problem for the heat and coolant?

 

I hope now, but have any of you had heater problem with the fan not making power to bring the air out?

 

the temp is at 180 the truck is not over heating at all. the heat in the back doesnt work because of a valve before the heater core is not working. but the front is blowing a little.