Step 4-Limit Control Check
After furnace has been in operation for at least 15 minutes, restrict
return-air supply by blocking filters or closing return registers and
allow furnace to shut down on high limit. The burner should shut
off, and main blower should continue to run.
Remove restriction, and burner should come back on in a few
minutes.
Step 5-For Year-Round Air Conditioning
This furnace is designed for use in conjunction with cooling
equipment to provide year-round air conditioning. The blower has
been sized for both heating and cooling, however, fan motor speed
may need to be changed to obtain necessary cooling airflow.
Step 6-Heating
The blower speed is factory set to deliver required airflow at
normal duct static pressure.
Step 7-Cooling
The blower speed may be field adjusted to deliver required airflow
for cooling application. (See Table 12.)
Step 8-Constant Blower Switch
This furnace is equipped with a constant low-speed blower option.
Whenever room thermostat is not calling for heating or cooling,
blower runs on low speed in order to provide air circulation. If
constant blower option is not desired, the rocker switch on top of
cabinet may be used to turn off constant speed.
MAINTENANCE
The ability to properly perform maintenance on this equip-
ment requires certain expertise, mechanical skills, tools, and
equipment. If you do not possess these, do not attempt to
perform any maintenance on this equipment other than those
procedures recommended in the User’s Manual. FAILURE
TO FOLLOW THIS WARNING COULD RESULT IN
POSSIBLE DAMAGE TO THIS EQUIPMENT, SERIOUS
PERSONAL INJURY, OR DEATH.
Before performing any service functions, unless operations
specifically require power to be on, make sure all utilities are
turned off upstream of appliance. Failure to comply with this
warning will cause a fire hazard and/or bodily harm.
To avoid personal injury, make sure electrical supply power
is off before servicing. Failure to follow this warning could
lead to electrical shock, fire, or death.
Step 1-General
In order to keep this furnace in good operating condition and to
maintain its warranty, the furnace MUST be serviced on an annual
basis. This servicing includes a nozzle change, a burner inspection,
a visual check of tube passages through flue outlet and cleanout
ports, and a visual inspection of combustion chamber when burner
is removed.
Depending on above inspection, service could also include a
cleaning and vacuuming of heat exchanger tubes and possibly the
heat exchanger drum section.
Removal of any heat exchanger components which are sealed by
gaskets requires replacement of gasket.
Failure to replace any heat exchanger gaskets with new
gaskets when any heat exchanger plates or covers are re-
moved could lead to heat exchanger leakage, sooting, and/or
a hazardous condition capable of causing bodily harm.
This furnace should never be operated without an air filter.
Disposable filters should be replaced at least once a year. If
equipped to provide cooling, filters should be replaced a minimum
of twice a year. Permanent filters should be cleaned at least twice
a year.
NOTE:
ALWAYS KEEP MAIN OIL VALVE TURNED OFF IF
BURNER IS SHUT DOWN FOR AN EXTENDED PERIOD OF
TIME.
Step 2-Oil Burner
For optimum performance, oil burner nozzle should be replaced
once a year. Contact your service technician if you are unsure of
this procedure.
The procedure for nozzle installation and/or replacement is out-
lined in oil burner instruction manual which came with furnace.
After replacement of nozzle, burner should be adjusted in accor-
dance with Combustion Check section of this instruction.
Table 10-Burner Input and Nozzle Size and Pump
Pressure
FURNACE
INPUT
(BTUH)
INPUT
USGPH
NOZZLE
REAL PUMP
PRESSURE
SPECIFICATION
PUMP PRESSURE
70,000
0.50
0.50-70W
100
100
91,000
0.65
0.55-70B
140
140
105,000
0.75
0.65-70B
133
130
120,000
0.85
0.75-70B
128
130
140,000
1.00
0.85-70B
138
140
155,000
1.10
0.85-70B
167
170
Table 11-Speed Selection
UNIT
SIZE
FURNACE
INPUT
(BTUH)
RECOMMENDED
BLOWER
SPEED
105-12/
120-20
70,000/119,000
Med-Low
91,000/140,000
Med-High
105,000/154,000
High
Fig. 5-Fan Off Time DIP Switch Settings
(Black Box Represents Switch Position)
A95115
1
2
60 Sec
1
2
90 Sec
DELAY OFF DIP SWITCH SETTINGS
1
2
1
2
1
2
120 Sec
1
2
150 Sec
10
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