Hi i have a master space heater model 150 paraffin, runs ok with the cover off but when i put the cover back on it stops. The flame out button clicks to shut the heater down. any info please

These units have a air pump on the back of the fan motor. Has anyone messed with the settings? The pump usually runs off of 5 to 6 lbs. of pump pressure. This is what controls the fuel flow that is sprayed out of the fuel injector. This unit also should have a photo eye for flame out control. It is positioned near the ignitor looking though a hole in the combustion chamber. Make sure it is clean and looking in the hole. Make sure your ignitor is working also.

Cant find a pump for my master space heater