I have a carrier frnace with behavioral issues. I believe it is a 58GFA. Well, the exhaust fan runs on and on but nothing happens. My nephew is a rapair man at an apartment and he came over and put a wire on the "pressure" switch and now the furnace does work now. The exhaust fan comes on and the gas valve turns on and lets the pilot light the burners. However, they are noisier than I remember and flames touch the tops of the holes where they go into the furnace cabinet and "spray" somehwat. Now when the whole house fan comes on they turn orange but seem to straighten out and go into the cabinet like they should. Finally, I noticed vent pipe that goes into the waterheater and then up into the cieling is not as hot. The pilot also goes out and has to be relit almost everytime. Also I see a lot of ashes everywhere. I don't know if this is one problem or several. Any advice would be great.