<strong>Yahoo Message Number: 8059</strong>Hi Dan,<br/><br/>On your model coach, one pump is for your air system, the other should be a vacuum pump for your heater controls. You may have a defective pump, a bad hose, but it should be vacuum related. Take the flexible rubber hose off the pump and block it with your finger. If the pump stops, you will know your problem is up stream. That hose...