Nordyne O4LD-140A-16F, O4LD-168A-16F, O4LD-140A-16-R, O4LD-168A-16-R Maintenance Manual

Installation, Operation and

Maintenance Manual

O4LD Oil-Fired Lowboy

Warm Air Furnaces

FOR YOUR SAFETY:

Do not store or use gasoline or other flammable liquids or

vapors in the vicinity of this, or any other appliance.

ALL INSTALLATIONS MUST MEET

ALL LOCAL, PROVINCIAL/STATE,

AND FEDERAL CODES WHICH MAY

DIFFER FROM THIS MANUAL

Read this complete manual before
beginning installation. These instructions
must be kept with the furnace for future
reference.

1

Table of Contents

1. Introduction..........................................................................................................................................................3

2. Heat Loss..............................................................................................................................................................3

3. Location of Unit ...................................................................................................................................................3

4. Air Conditioning Applications............................................................................................................................3

5. Combustion Air....................................................................................................................................................4

6. Chimney Venting .................................................................................................................................................4

7. Barometric Damper Control ...............................................................................................................................4

8. Fan and Limit Control..........................................................................................................................................5

9. Electrical Connections........................................................................................................................................5

10. Humidifier...........................................................................................................................................................5

11. Piping Installation..............................................................................................................................................5

12. Oil Filter ..............................................................................................................................................................6

13. Oil Burner Nozzles.............................................................................................................................................6

14. Oil Burner Adjustment ......................................................................................................................................6

15. Burner Electrodes..............................................................................................................................................6

16. Burner Primary Control.....................................................................................................................................6

17. Combustion Chamber.......................................................................................................................................7

18. Circulating Air Blower.......................................................................................................................................7

19. Maintenance and Service..................................................................................................................................8

20. Operating Instructions......................................................................................................................................9

A.1 Oil Burner Air Adjustment..............................................................................................................................11

A.2 Burner Electrodes...........................................................................................................................................11

A.3 Start-Up............................................................................................................................................................11

21. Final Check-Out...............................................................................................................................................17

PARTS LISTS...........................................................................................................................................................18

Homeowner’s Reference Table.............................................................................................................................24

2

1. INTRODUCTION

2. HEAT LOSS

Please read these instructions completely and
carefully before installing and operating the
furnace.

Models O4LD-140A-16-R and O4LD-168A-16-R
are rear breeched oil fired forced air low boy
furnace, with output capacities ranging from
79,000 Btu/h to 143,000 Btu/h.

Models O4LD-140A-16-F and O4LD-168A-16-F
are front breeched oil fired forced air lowboy
furnaces, with output capacities ranging from
79,000 Btu/h to 143,000 Btu/h.

DO NOT USE GASOLINE, CRANK CASE
OIL, OR ANY OIL CONTAINING
GASOLINE.

All models are CSA listed, for use with No. 1
(Stove) and No. 2 (Furnace) Oil. Please refer to
the tables in Appendix A for performance and
dimensional data.

In the United States of America, the installation
of the furnace and related equipment shall be
installed in accordance with the regulations of

NFPA No. 31, Installation of Oil Burning
Equipment, as well as in accordance with local

codes.
In Canada, the installation of the furnace and

related equipment shall be installed in
accordance with the regulations of CAN/CSA -

B139, Installation Code For Oil Burning
Equipment, as well as in accordance with local

codes.
Regulations prescribed in the National Codes

and Local regulations take precedence over the
general instructions provided on this installation
manual. When in doubt, please consult your
local authorities.

All models are shipped completely assembled
and pre-wired. The furnace should be carefully
inspected for damage when being unpacked.

The maximum hourly heat loss for each heated
space shall be calculated in accordance with the
procedures described in Manual J

. titled, "Load
Calculation" published by the Air Conditioning
Contractors of America, or method suitable for
local conditions or prescribed by local codes.
The calculation results obtained should be in
substantial agreement with, and not less than
those obtained using the procedure described in
Manual J

.

In Canada, the maximum hourly heat loss for
each heated space shall be calculated in
accordance with the procedures described in the
manuals of the Heating, Refrigeration and Air
Conditioning Institute of Canada (HRAI), or by
method suitable for local conditions.

3. LOCATION OF UNIT

The furnace should be located such that the flue
connection to the chimney is short, direct and
consists of as few elbows as possible. When
possible, the unit should be centralized with
respect to the supply and return air ductwork. A
central location minimizes the trunk duct sizing.
All models may be installed on combustible
floors.

The minimum installation clearances are listed in
Table 1.

Table 1: Installation Clearance

Clearance to / for

Location

Top 3 in. 3 in.

Bottom 0 in. 0 in.

S/A Plenum 0 in. 0 in.

Rear 1 in. 24 in.

Side 1 6 in. 6 in

Side 2 6 in. 18 in.

Front 24 in. 24 in.

Flue Pipe 9 in. 9 in.

Enclosure Standard Standard

Combustible

s

Service

4. AIR CONDITIONING APPLICATIONS

If the furnace is used in conjunction with air
conditioning, the furnace shall be installed in
parallel with or upstream from the evaporator coil

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152B0801

to avoid condensation in the heat exchanger. In
a parallel installation, the dampers or air
controlling means must prevent chilled air from
entering the furnace. If the dampers are
manually operated, there must be a means of
control to prevent the operation of either system
unless the dampers are in the full heat or full
cool position. The air heated by the furnace shall
not pass through a refrigeration unit unless the
unit is specifically approved for such service.

The blower speed must be checked and
adjusted to compensate for the pressure drop
caused by the evaporator coil. Refer to Appendix
B for recommended wiring and electrical
connections of the air conditioning controls.

5. COMBUSTION AIR

If the furnace is installed in a closet or utility
room, two openings must be provided connecting
to a well-ventilated space (full basement, living
room or other room opening thereto, but not a
bedroom or bathroom). One opening shall be
located above the level of the upper vent
opening and one opening below the combustion
air inlet opening in the front of the furnace. Each
opening shall have a minimum free area of 1½
square inches per 1,000 Btu/h of total input
rating of all appliances installed in the room.

For furnaces located in buildings of unusually
tight construction, such as those with high quality
weather stripping, caulking, windows and doors,
or storm sashed windows, or where basement
windows are well sealed, a permanent opening
communicating with a well ventilated attic or with
the outdoors shall be provided, using a duct if
necessary. The duct opening shall have a free
area of 1½ square inches per 1,000 Btu/h of total
input rating of all appliances to be installed.
When a furnace is installed in a full basement,
infiltration is normally adequate to provide air for
combustion and draft operation. Furnace rooms
under 65m³ (700 ft³) should automatically be
treated as confined space.

6. CHIMNEY VENTING

The flue pipe should be as short as possible with
horizontal pipes sloping upward toward the
chimney at a rate of one-quarter inch to the foot.
The flue pipe should not be smaller in cross
sectional area than the flue collar on the furnace.
The flue pipe should connect to the chimney
such that the flue pipe extends into, and

terminates flush with the inside surface of the
chimney liner. Seal the joint between the pipe
and the lining. The chimney outlet should be at
least two feet above the highest point of a
peaked roof. All unused chimney openings
should be closed. Chimneys must conform to
local, provincial or state codes, or in the absence
of local regulations, to the requirements of the
National Building Code.

NOTE: THE FURNACE IS APPROVED FOR

USE WITH TYPE L VENT OR
EQUIVALENT.

THE FURNACE MUST BE CONNECTED
TO A FLUE HAVING SUFFICIENT
DRAFT AT ALL TIMES TO ENSURE
SAFE AND PROPER OPERATION OF
THE APPLIANCE.

NOTE: THE RECOMMENDED FLUE DRAFT

PRESSURE IS -0.02 IN. W.C. (AS
MEASURED UPSTREAM OF THE
BAROMETRIC DRAFT REGULATOR).

The flue pipe must not pass through any floor or
ceiling, but may pass through a wall where
suitable fire protection provisions have been
installed. Refer to the latest edition of NFPA 31
for regulations governing the installation of oil
burning equipment. In Canada, refer to the latest
edition of CAN/CSA B-139 for rules governing
the installation of oil burning equipment.

See appendix A for burner set-up.

7. BAROMETRIC DAMPER CONTROL

This control, also known as a draft regulator,
automatically maintains a constant negative
pressure in the furnace to obtain maximum
efficiency. It ensures that proper pressures are
not exceeded. If the chimney does not develop
sufficient draft, the draft control cannot function
properly. The draft regulator, when installed
should be in the same room or enclosure as the
furnace and should not interfere with the
combustion air supplied to the burner. The
control should also be located near the furnace
flue outlet and installed according to the
instructions supplied with the regulator. The flue
outlet pressure (measured between the furnace

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152B0801

and draft regulator) should be set to -0.02 in.
w.c.

8. FAN AND LIMIT CONTROL

The L6064A temperature sensitive fan switch is

actuated by a helical bi-metal sensing element
enclosed in a metal guard, and controls the
circulating air blower. This provides a delay
between the burner ignition and blower start-up
to eliminate excessive flow of cold air when the
blower comes on. Blower shutdown is also
delayed to remove any residual heat from the
heat exchanger and improve the annual
efficiency of the furnace. Fan on settings of 110º
F to 130º F (43º C to 55º C) and fan off settings
of 90º F to 100º F (32º C to 37ºC) will usually be
satisfactory.

9. ELECTRICAL CONNECTIONS

The furnace is listed by CSA to the North
American standard. The furnace is factory wired
and requires minimal field wiring. In the United
States, the wiring must be in accordance with the
National Fire Protection Association NFPA-70,
National Electrical Code, and with local codes
and regulations. In Canada, all field wiring
should conform to CAN/CSA C22.1 Canadian
Electrical Code, Part 1, and by local codes,
where they prevail.

The furnace should be wired to a separate and
dedicated circuit in the main electrical panel;
however, accessory equipment such as
electronic air cleaners and humidifiers may be
included on the furnace circuit. Although a
suitably located circuit breaker can be used as a
service switch, a separate service switch is
advisable.

Furnace Power Requirements

Furnace Model

All Models 120 15 1 60

Volts

AC

Amps

∅

Hz

Accessories requiring 120 VAC power sources
such as electronic air cleaners and humidifier
transformers may be powered 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 windings of the
direct drive motor.

Thermostat wiring connections and air
conditioning contactor low voltage connections
are shown in the wiring diagram in Appendix B.
Some micro-electronic thermostats require
additional controls and wiring. Refer to the
thermostat manufacturer's instructions.

The thermostat should be located approximately
5 feet above the floor, on an inside wall where
there is good natural air circulation, and where
the thermostat will be exposed to average room
temperatures. Avoid locations where the
thermostat will be exposed to cold drafts, heat
from nearby lamps and appliances, exposure to
sunlight, heat from inside wall stacks, etc.

The thermostat heat anticipator should be
adjusted to the amperage draw of the heating
control circuit as measured at the "R" and "W"
terminals of the thermostat. To reduce the risk of
damaging the heat anticipator, do not measure
this current with the thermostat connected to the
circuit. Measure the amperage by connecting an
ammeter between the two wires that will connect
to the thermostat "R" and "W" terminals.

10. 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
instructions. Water or water droplets from the
humidifier should not be allowed to come into
contact with the furnace heat exchanger. Do not
use direct drive motor connections as a source
of power for 120 VAC humidifiers and humidifier
transformers.

11. PIPING INSTALLATION

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152B0801

The entire fuel system should be installed in
accordance with the requirement of NFPA No. 31
and local codes and authorities. In Canada, the
entire fuel system should be installed in
accordance with the requirement of CAN/CSA B­139, and local regulations. Use only an approved
fuel oil tanks piping, fittings and oil filter.

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
instructions shipped with the furnace.

12. OIL FILTER

All fuel systems should include a high quality oil
filter between the fuel oil storage tank and the oil
burner.

13. OIL BURNER NOZZLES

Both front breech and rear breech models are
certified for multiple firing rates, ranging from
output capacities of 79,000 to 143,000 Btu/h. By
manipulating the oil burner nozzle, and
temperature rise, these furnaces may be fired at
an ideal rate for a wide range of structures. Refer
to Table A-1, and the furnace rating plate to
determine the proper combinations.

14. OIL BURNER ADJUSTMENT

The burner air supply is adjusted to maintain the

fuel to air ratio to obtain ideal combustion

conditions. A lack of air causes "soft" and "sooty"
flames, resulting in soot build-up throughout the
heat exchanger passages. Excess combustion
air causes a bright roaring fire and high stack
temperatures resulting in poor fuel efficiency.
Maximum combustion efficiency is achieved with
a No. 1 smoke spot on the Bacharach Scale.
This is not necessarily the optimum setting;
however, because dust will inevitably build up on
the air moving components of the oil burner
assembly. This will result in decreased air supply
with the potential result of soot building up in the
flue gas passageways of the heat exchanger.
Soot behaves as an insulator and impairs good
heat transfer. Stack temperature will increase,
and the overall efficiency will decrease. As a
means of avoiding this problem, it is advisable to
adjust the air supply to provide no more than a
trace smoke spot on the Bacharach Scale.

BEFORE OPERATING THE FURNACE
CHECK BURNER ALIGNMENT WITH
COMBUSTION CHAMBER. THE END
CONE OF THE AIR TUBE MUST BE
CENTRED TO THE ACCOMODATING
RING PROVIDED IN THE DESIGN OF
THE COMBUSTION CHAMBER.
ADJUST AS NECESSARY.

15. BURNER ELECTRODES

Correct positioning of the electrode tips with
respect to each other, to the fuel oil nozzle, and
to the rest of the burner is essential for smooth
light ups and proper operation. Refer to the oil
burner instructions shipped with the furnace for
electrode specifications.

NOTE: Beckett AF Series Burner electrode
specifications have been revised. They should
be adjusted to be 5/16” above the nozzle
centerline.

16. BURNER PRIMARY CONTROL

The furnace is equipped with a primary
combustion control, sometimes refer to as the
burner relay or burner protector relay, which
uses a light sensing device (cad cell) located in
the burner housing, to monitor and control
combustion. Over time, dust or combustion
residuals can build up on the lens of the cad cell
impairing its response to the flame. The cad cell
should be checked for cleanliness and proper
alignment if the primary control frequently shuts
down combustion.

ALL FURNACE CONTROLS ARE
SENSITIVE AND SHOULD NOT BE
SUBJECTED TO TAMPERING. IF
PROBLEMS PERSIST, CALL YOUR
SERVICE CONTRACTOR.

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152B0801

17. COMBUSTION CHAMBER

This furnace is equipped with a high quality
cerafelt combustion chamber. It is held in place
by a support bracket and stainless steel retaining

band and clamp. CHECK THE ALIGNMENT OF

THE COMBUSTION CHAMBER AND OIL
BURNER BEFORE FIRING. IT IS POSSIBLE
FOR THE COMBUSTION CHAMBER TO SHIFT
IF SUBJECTED TO ROUGH HANDLING
DURING TRANSIT. The combustion chamber

should be inspected for damage or carbon build
up whenever the oil burner is removed for repairs
or routine maintenance.

It is possible and acceptable to use a single
blower speed for both heating and cooling
modes. The simplest method to connect the
wiring from both modes is to use a "piggy-back
connector" accommodating both wires on a
single motor tap. It is also acceptable to connect
the selected motor speed with a pig tail joined to
both heating and cooling speed wires with a wire
nut. As a safety precaution against accidental
disconnection of the wires by vibration, it is
advisable to secure the wire nut and wires with a
few wraps of electricians tape.

DO NOT START THE BURNER UNLESS
THE BLOWER ACCESS DOOR IS
SECURED IN PLACE.

18. CIRCULATING AIR BLOWER

Both front breech and rear breech models are
equipped with direct drive blower systems. Direct
drive blower speed adjustments are not normally
required in properly sized extended plenum duct
systems. The motor RPM and air CFM delivery
will vary automatically to accommodate
conditions within the usual range of external
static pressures typical of residential duct
systems. Under-sized duct systems may require
a higher blower speed to obtain a reasonable
system temperature rise. Some older duct
systems were not designed to provide static
pressure. They typically feature special reducing
fittings at each branch run and lack block ends
on the trunk ducts. These systems may require
modification to provide some resistance to the
airflow to prevent over-amping of the direct drive
blower motor. Selecting a lower blower speed
may correct this problem.

Direct drive blower speeds are adjusted by
changing the "hot" wires to the motor winding
connections. Please refer to wiring diagram in
Appendix B or the wiring diagram label affixed to

the furnace. THE NEUTRAL WIRE (normally

the white wire) IS NEVER MOVED TO ADJUST
THE BLOWER SPEED.

DO NOT CONNECT POWER LEADS
BETWEEN MOTOR SPEEDS. THE
NEUTRAL WIRE MUST ALWAYS BE
CONNECTED TO THE MOTOR'S
DESIGNATED NEUTRAL TERMINAL.

DISCONNECT THE POWER SUPPLY TO
THE FURNACE BEFORE OPENING THE
BLOWER ACCESS DOOR TO SERVICE
THE AIR FILTER, FAN AND MOTOR.
FAILURE TO SHUT OFF POWER
COULD ALLOW THE BLOWER TO
START UNEXPECTEDLY, CREATING A
RISK OF DEATH OR PERSONAL
INJURY.

If the joining of the blower speed wiring is done
in the furnace junction box, tape off both ends of
the unused wire.

Do not use the blower speed wires as a
source of power to accessories. The unused

motor taps auto-generate sufficiently high
voltages to damage accessory equipment.

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152B0801

19. MAINTENANCE AND SERVICE

A: Routine Maintenance By Home Owner

Other than remembering to arrange for the
annual professional servicing of the furnace by
the service or installation contractor, the most
important routine service performed by the
homeowner is to maintain the air filter or filters. A
dirty filter can cause the furnace to over-heat, fail
to maintain indoor temperature during cold
weather, increase fuel consumption and cause
component failure.

The furnace filter(s) should be inspected,
cleaned or replaced monthly. The furnace is
factory equipped with a semi-permanent type
filter. If the filter is damaged, replace with filters
of the same size and type. (See Appendix A,
Table A-3).

During the routine service, inspect the general
condition of the furnace watching for signs of oil
leaks in the vicinity of the oil burner, soot forming
on any external part of the furnace, soot forming
around the joints in the vent pipe, etc. If any of
these conditions are present, please advice your
service or installation contractor.

Annual Service By Contractor

the gaskets. If the gaskets are broken, remove
the remnants and replace with new gaskets.
Replace the cleanout covers and screws.

The blower motor is factory sealed and requires
no routine lubrication.

Inspect the blower fan. Clean if necessary.

Oil Burner Maintenance: Inspect and clean the
oil burner. Be sure to remove any dust
accumulation in the air band, air shutter, and
blower wheel. The oil burner nozzle and oil filter
should be replaced on an annual basis. The
burner motor is factory sealed and requires no
routine lubrication.

The venting system should be cleaned and
inspected for signs of deterioration. Replace
pitted or perforated vent pipe and fittings. The
barometric damper should open and close freely.

All electrical connections should be checked to
ensure tight connections. Safety controls such as
the high limit controls should be tested for
functionality. The fan control should be checked
to ensure that the "fan off" function continues to
stop the blower fan at a suitable temperature,
usually between 90°F to 100°F.

THE COMBUSTION CHAMBER (FIREPOT)
IS FRAGILE. USE CARE WHEN
INSPECTING AND CLEANING THIS AREA.

The heat exchanger, and flue pipe on rear
breach units, should be inspected periodically
and cleaned if necessary. If cleaning is

necessary, SHUT OFF POWER TO THE
FURNACE and remove the burner. Using a stiff

brush with a wire handle, brush off scale and
soot from inside the drum and flue pipe. The
Flue Connector shall be removed to inspect and
clean the flue pipe area. To clean the radiator,
remove the round covers on the two pipes
located on the front panel between the front
panel and the flue pipe. Remove the covers
carefully to avoid tearing the gaskets. A wire
brush can be used to loosen dirt and debris on
the inside surfaces of the radiator. Clean out all
accumulated dirt, soot and debris with a wire
handled brush and industrial a vacuum cleaner.
Before replacing the clean-out covers, inspect

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152B0801