Suburban DD-17DSI, Service Manual

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1. 1/8" spark gap between electrode and
ground.
2. 1/4" spark gap between ground and
flame sensor.
3. Maintain electrode position of 3/16" over
burner ports.
Figure 33
REMOTE FLAME SENSE
MAINTENANCE
Preventative maintenance is essential if an RV owner is to have reliable, safe operation of his furnace. Two important areas to watch
closely in order to assure safe, reliable operation are the venting and the main burner.
An obstruction in the vent or main burner will reduce the combustion air which results in incomplete combustion. Whenever incomplete
combustion occurs, the by-products are carbon monoxide (CO) and soot. If the furnace outside exhaust vent shows black soot forming,
the furnace should not be operated until the problem is corrected. Two common causes are:
1. Restriction in the vent or furnace intake (screens, wasp nests, tape).
2. Dirty burner.
If operation of the furnace continues under these conditions, it could result in serious injury to the occupants of the RV or even death.
Cleaning of the main burner and an inspection of the venting system should be done at least once a year, preferably just before the
beginning of the heating season. Some RV owners and service personnel have the false assumption that if a furnace has not been used,
it will not require cleaning.
NOT SO! A furnace which has not been used for some time could be more in need of cleaning than a furnace
which has been used extensively.
Dust and lint should be removed from the room air blower wheel and sail switch. A build up of dust and lint on the blower wheel can cause
the motor to drag and not generate enough air flow to engage the sail switch. Dust accumulation on the sail switch will restrict the travel
of the actuator arm to where the air flow across the paddle will not sail it in and complete the valve circuit.
A yearly inspection should be made of all gaskets on the furnace. If any gaskets show signs of leakage or deterioration, they must be
replaced.
Figure 34
Figure 35