31
d. If the light (indicator light for R7184 control;
green light for 7505 control) stays off while
the fl ame is on, check the cad cell sighting
for view of the fl ame.
e. If the burner locks out, check the cad cell
resistance. (See Table 10)
f. If the burner stays running, the system is
operational.
g. If the light (indicator light for R7184 control;
green light for 7505 control) is off, check
the cad cell assembly after disconnecting
the line voltage.
Burner will not start and the indicator light
is fl ashing at 2 seconds on, 2 seconds off
(for R7184) or the green light is fl ashing
(for 7505).
1. Hold the reset button down for 1 – 2 seconds.
If indicator light continues to fl ash, wait for
60 – 70 seconds. If it still continues to fl ash,
replace the primary control.
To check cad cell resistance:
Press and re-
lease the button during the run mode, with the
igniter off. The light (yellow light for 7505 control)
will fl ash to indicate the cad cell resistance. For
proper burner operation, it is important that the
cad cell resistance is under 1600 Ohms. For cad
cell resistance, see Table 10.
18. MAINTENANCE
By Homeowner
1. Return Air - On some closet installations the
return air opening to the furnace may be on
the fl oor, on the door, on the side wall of the
closet, or some combination of these. The
upper grille on the front of the furnace admits
return air to the blower. Return air must be
provided back to the circulating blower in order
to provide air distribution.
2. Filters - At least twice each season (more often
in dusty areas) remove and clean the air fi lters
with a vacuum or with warm water and soap.
Reinstall when dry. Also clean dust and lint
around furnace and in the furnace vestibule.
(Figure 35.)
3. Seasonal Service Information - During ex-
tremely cold weather, ice may form on the
furnace roof jack. Small amounts of ice form-
ing on the roof jack will present no problems
to proper furnace operation. Excessive ice
formation could restrict the combustion air
supply to the burner, causing ineffi cient burner
operation. If excessive ice has formed on the
air inlet or exhaust portions of the roof jack,
it must be carefully removed (Figure 36).
By Serviceman
All furnaces need periodic service at the
beginning of each heating season. Call your
serviceman to:
a. Remove the air circulator and clean all dust and
lint from the unit with a stiff bristle brush.
b. Inspect the combustion chamber blower
compartment, fl ue collar and Roof Jack.
c. Check the gas valve (if applicable) and fuel
line connections for leaks.
d. Make any adjustments necessary for good
operation.
WARNING:
Use of furnace or air conditioning
components that are not included
in the certifi cation of this appliance
may create a hazard, invalidate the
certifi cation, and in many states, make
installations illegal. Listed NORDYNE
air conditioning components are
specifi ed on the furnace label.
ADDITIONAL OIL
FURNACE MAINTENANCE
In addition to the preceding, the following should
be performed by a qualifi ed service contractor at
least once each season for oil-fi red furnaces:
Figure 36. Roof Jack
Check for
Ice Here
WARNING:
Do not obstruct any return air open-
ings, including the grille on the fur-
nace. To do so may cause the furnace
to activate the high limit and shut
down, or it may cause asphyxiation.
