Jack, Maybe the vacuum line that connects to the water valve that circulates hot water into the heater core isn't connected. It could have easily been disconnected by accident. To see if that is the case....when looking directly at the engine compartment, you will see a very small vacuum line coming from the drivers side of the firewall leading to the middle of the back of the engine. That is the vacuum line that goes from the mode switch to the water valve telling it to open or shut depending on the position the mode switch is in. Hope that helps. Later, Nick 1852 <A HREF="Http://members.aol.com/njp548">Http://members.aol.com/njp548</A>