The furnace switch (service switch) should be clearly marked,
installed in an easily accessible area between the furnace and
furnace room entry, and be located in such a manner to reduce
the likelihood that it would be mistaken as a light switch or simi-
lar device.
Accessories requiring 120 VAC power sources such as elec-
tronic air cleaners and humidifier transformers may be pow-
ered from the furnace circuit, but should have their own
controls
Do not use the direct drive motor connections as a power
source, since there is a high risk of damaging the accessories
by exposure to high voltage from the auto--generating wind-
ings of the direct drive motor.
Thermostat wiring connections and air conditioning contactor
low voltage connections are shown in the wiring diagrams on
Page 12. Some micro--electronic thermostats require addi-
tional controls and wiring. Refer to the thermostat manufac-
turer's instructions.
CAUTION: A room thermostat with independent
heat/cool circuit is required.
The thermostat should be located approximately 5 feet above
the floor, on an inside wall where there is good natural air circu-
lation, and where the thermostat will be exposed to average room
temperatures. Avoid locations where the thermostat will be ex-
posed to cold drafts, heat from nearby lamps and appliances, ex-
posure to sunlight, heat from inside wall stacks, etc.
NOTE: Some electronic thermostats do not have ad-
justable heat anticipators. They may have other type
cycle rate adjustments. Follow the thermostat manu-
facturer's instructions.
HUMIDIFIER
A humidifier is an optional accessory available through most
heating supplies outlets. Installation should be carried out in
accordance with the humidifier manufacturer's installation in-
structions. Water or water droplets from the humidifier should
not be allowed to come into contact with the furnace heat ex-
changer. Do not use direct drive motor connections as a source
of power for 120 VAC humidifiers and humidifier transformers.
PIPING INSTALLATION
The entire fuel system should be installed in accordance with
the requirements of ANSI NFPA No. 31 in the United States or
CAN/CSA B--139 in Canada, and local regulations. Use only
an approved fuel oil tanks piping, fittings and oil filter.
Ensure that all fittings used in a copper oil line system are high
quality flare fittings. Do not use compression fittings.
Pressurized or gravity feed installations must not exceed 10
PSIG on the inlet line or the return line at the pump. A pressure
greater then 10 PSIG may cause damage to the shaft seal.
The furnace may be installed with a one pipe system or gravity
feed or lift. The maximum allowable lift on a single line system is
8 ft. Lift should be measured from the bottom (outlet) of the tank
to the inlet of the burner.
Sizing a single line system is complex because of the difficulty
estimating the pressure drop through each fitting, bend and
component in the line. In general, keep single line systems
short as possible. If the furnace is to be installed in a sus-
pended position, a two pipe system may be a better alternative.
Two--stage oil pumps may be used with both single line and
two line systems. Two--stage pumps are available from your
HVAC wholesaler. Table 3 lists allowable line lengths (horizon-
tal plus vertical) for single and two stage oil pumps.
In retrofit applications where an existing oil line system is in
place, a vacuum check will help determine if a two--stage oil
pump is necessary. The vacuum in a system using a single
stage oil pump should not exceed 6" Hg. The vacuum in a sys-
tem using a two--stage oil pump should not exceed 15" Hg. For
additional information, refer to the instruction information sheet
affixed to the oil burner.
Install the oil filter as close to the burner as possible. For further
details of the oil supply tank and piping requirements, please
refer to the instructions and illustrations in the oil burner and oil
pump instructions shipped with the furnace.
OIL FILTER
All fuel systems should include an oil filter between the fuel oil
storage tank and the oil burner. When using an oil burner noz-
zle smaller than 0.65 U.S. Gallons Per Hour, install an addi-
tional 7 to 10 micron filter as close as possible to the oil burner.
OIL BURNER NOZZLES
These furnaces are certified for multiple firing rates, ranging
from 60,000 to 181,000 Btu/h depending on model. By manipu-
lating the oil burner nozzle, flame retention head, static plate
and temperature rise, the furnace may be fired at an ideal rate
for a wide range of structures. Refer to Table 4, and the furnace
rating plate to determine the proper combinations.
CAUTION: Before operating the furnace check
burner alignment with the combustion chamber. The
end cone of the air tube must be centered to the ac-
commodating ring provided in the design of the com-
bustion chamber. Adjust as necessary.
Unitary Products Group
7
035-14289-000 Rev. A (0701)
SINGLE STAGE
2-STAGE
LIFT
3/8" O.D.
TUBING
1/2" O.D.
TUBING
3/8" O.D.
TUBING
1/2" O.D.
TUBING
1
53
100
68
100
2
49
100
65
100
3
45
100
63
100
4
41
100
60
100
5
37
100
58
100
6
33
100
55
100
7
29
100
53
100
8
25
99
50
100
9
21
83
48
100
10
17
68
45
100
12
13
52
42
100
12
—
—
37
100
14
—
—
32
100
16
—
—
27
100
18
—
—
22
88
TABLE 3 - OIL PIPING LENGTHS (FEET)
Set the heat anticipator in the room thermostat to .4
amps. for models P*HBX12F080, P*DHX12F080 &
P*DHX16F120; for other models set heat anticipator at
.2 amps. Setting it lower will cause short cycles. Setting
it higher will cause the room temperature to exceed the
setpoint.