I have a Carrier Unit that has a gas furnace. The control board on this unit is CES0110057 02. The blower motor is intermittent. When the thermostat is placed in the "ON" position the blower will operate but then occasionally stop blowing. When the thermostat is placed in "Auto" position, it will operate for a time, cycling the blower. But then it will stop. I can then open the service port, exposing the board, wait some indefintite time, and at some point in time, it will start blowing again. At some other time, I don't even have to open the service port. I just place the thermostsat in "Fan On" mode and at some point it will start operating on its own. This problem has no rhyme orr reason. Works the same whether in Heat/Cool modes. I'm thinking that it may be a defective board but not sure. Any ideas?