Heater smokes

Step 1: Exhaust pipe

Check exhaust pipe for damage (cross section reduced)

Possible defect


Mechanical damage

Install new exhaust pipe

Partially blocked

Clean exhaust pipe

Step 2: Fuel pump

Check delivery quantity of fuel pump

Possible defect


Excessive fuel

Correctly adjust delivery quantity

Step 3: Combustion air intake

Check combustion air intake for free passage (visual check).

Possible defect


Intake blocked

Clean combustion air intake

Step 4: Combustion air blower motor

Check combustion air blower motor speed.

Possible defect


Battery voltage too low

Charge battery

Blower fan loose (chafes)

Remove combustion air blower, secure blower fan (note air gap of .039”/1 mm) and install new blower fan if necessary

Speed is not attained at nominal voltage (6400-7100 rpm)

Remove motor and check, install new one if necessary