Electric wall heater keeps tripping off. What might be the causes?
What is the cover doing that could be causing this unit to keep tripping off?


The cover is holding in heat and the reset you are pushing is tripped by heat. Usually, the reset trips because the unit is drawing too much current which creates heat in the thermal trip device.

Is there anything blocking air flow to the unit? The heater needs air to flow freely otherwise it could overheat and trip out. 

If it is tripping out without anything blocking air flow this means the heating coil is not functioning properly or the thermal unit is faulty.