1. What would cause my copper hotwater pipes to blacken with a sooty powder? We removed a wall during remodeling and found the pipes with a black sooty powder. It comes off on to your hand when touched.
Plus, we found a plug with blackened cooper also..?
Any help would be appreciated.

2. What would cause my honeywell rectangle thermostat to engage to egnite the oil burner, shut off within 1 min.. . on then off on then off again. The heat does does not come on long enough. I tried moving the duration setting inside the box to no avail. Either it comes on and off or not at all.

HELP! :(

Are you sure the soot is not mold that has grown in the moiture of a condensating copper pipe? 2. I'm guessing, the problem may be in furnace and not the thermostat.