OIL FIRED FURNACE

INSTALLATION AND OPERATION MANUAL

WITH USERS INFORMATION SECTION
MODELS:
OC2-56
OC5-85
OT5-85
OT11-105
OT16-125

OL2-56
OL5-85
OL11-105
OL16-125
OL20-151
OL33-200
OL37-250
OL39-320

OH2-56
OH3-72
OH5-85
OH11-105
OH16-125

? WARNING: IF THE INFORMATION IN THESE INSTRUCTIONS IS NOT FOLLOWED EXACTLY, A FIRE

OR EXPLOSION MAY RESULT CAUSING PROPERTY DAMAGE, PERSONAL INJURY, OR LOSS OF LIFE.
DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE VAPORS AND LIQUIDS IN THE VICINITY OF
THIS OR ANY OTHER APPLIANCE.

? WARNING: IMPROPER INSTALLATION, ADJUSTMENT, ALTERATION, SERVICE, OR MAINTENANCE

CAN CAUSE INJURY OR PROPERTY DAMAGE. REFER TO THIS MANUAL. FOR ASSISTANCE OR
ADDITIONAL INFORMATION CONSULT A QUALIFIED INSTALLER, OR SERVICE AGENCY.
PLEASE READ THESE INSTRUCTIONS PRIOR TO INSTALLATION, INITIAL FIRING, AND BEFORE
PERFORMING ANY SERVICE OR MAINTENANCE. THESE INSTRUCTIONS MUST BE LEFT WITH THE
USER AND SHOULD BE RETAINED FOR FUTURE REFERENCE BY QUALIFIED SERVICE PERSONNEL.
THERMO PRODUCTS, LLC.
PO BOX 217
NORTH JUDSON, IN 46366
PHONE: (574) 896-2133

MO-100G
ECN 4385-MA

MADE IN USA

I. SAFETY SECTION
This page contains various warnings and cautions found throughout the Oil Furnace
Manual. Please read and comply with the statements below.

?WARNING AND CAUTIONS:

?WARNING: This furnace is not to be used as a construction heater. See Page 1.
? CAUTION MUST BE TAKEN NOT TO EXCEED 90 ROTATION (OF THE FLUE
ELBOW) COUNTERCLOCKWISE FROM THE VERTICAL POSITION. See Page 2.
?WARNING: When cutting openings in the casing DO NOT CUT ANY SUPPORTING
CLIPS OR ANGLES. See Page 5.
?WARNING: The predetermined fan and limit locations on all of the Thermo Pride oil fired
furnaces have been tested and approved by Thermo Products, LLC. in conjunction with
Underwriters Laboratories, Inc. Any attempt to relocate these safety controls or replace these
safety controls with a control that is not approved, or is incompatible, may result in personal
injury, substantial property damage or death. See Page 6.
?WARNING: THE HEAT EXCHANGER MUST BE CLEANED BY A QUALIFIED
SERVICE PERSON. See Page 11.
?CAUTION: DO NOT ATTEMPT TO MAKE REPAIRS YOURSELF! See Page 13.
?WARNING: The area around the furnace should be kept free and clear of combustible
liquids and material, especially papers and rags. See Page 13.
?WARNING: NEVER burn garbage or refuse in your furnace. Never try to ignite oil by
tossing burning papers or other material into your furnace. See Page 13.
?WARNING: Thermo Products oil furnaces are designed to burn No. 1 or No. 2 distillate
fuel oil. NEVER USE GASOLINE OR A MIXTURE OF OIL AND GASOLINE. See Page
13.
?CAUTION: DO NOT ATTEMPT TO START THE BURNER WHEN:
1. Excess oil has accumulated,
2. The furnace is full of vapors
3. The combustion chamber is very hot.
IF ONE OR MORE OF THESE CONDITIONS EXIST, CONTACT A QUALIFIED
SERVICE PERSON. See Page 13.

All installations and services must be performed by qualified service personnel.

This page contains reproductions of the various instruction and warning labels placed on
the Thermo Pride Oil Furnaces. Please read and comply with the contents of these labels.

ii

All installations and services must be performed by qualified service personnel.

TABLE OF CONTENTS
SECTION
I. SAFETY SECTION
II. GENERAL INSTRUCTIONS
A. DRAFT REGULATORS
B. DUCT WORK/AIR CONDITIONING
C. FILTERS MOUNTED EXTERNAL TO FURNACE
D. FAN AND LIMIT POSITION AND LOCATION
E. BURNER INSTALLATION
F. HORIZONTAL FURNACE POSITIONS
G. EXTERNAL WIRE HARNESS LOCATIONS
H. BURNER SPECIFICATIONS AND APPLICATIONS
I. HEAT EXCHANGER CLEANING INSTRUCTIONS
III. USERS INFORMATION SECTION
A. OIL SUPPLY
B. COMBUSTION AIR SUPPLY
C. INSPECTION AREAS
D. STARTING THE BURNER
E. FILTER CLEANING AND LOCATIONS

BEGINNING PAGE
i
1
3
3
4
6
6
8
8
9
11
12
12
12
13
13
13

APPENDIX A

REPLACEMENT PARTS LIST

16

APPENDIX B

WIRING DIAGRAMS

26

iii

All installations and services must be performed by qualified service personnel.

II. GENERAL INSTRUCTIONS - READ BEFORE START OF INSTALLATION
1. The heating output capacity of the furnace proposed for installation should be based on a heat loss calculation
made according to the manuals provided by the Air Conditioning Contractors of America (ACCA) or the American
Society of Heating, Refrigeration and Air Conditioning Engineers, Inc. (ASHRAE).
2. All local codes and/or regulations take precedence over the instructions in this manual and should be followed
accordingly. In the absence of local codes, installation must conform with these instructions and regulations of the
National Fire Protection Association, and to the provisions of the National Electrical Code (ANSI/NFPA 70-1999 or
latest edition).
3. The installed furnace must be level and positioned in a central location with respect to outlet registers. It should be
located near the chimney to minimize any horizontal run of flue pipe, which may be required.
4. A furnace installed in a residential garage must be installed so the burner and ignition source are located higher
than 18 inches above the floor, unless the required combustion air is taken from the exterior of the garage. Also, the
furnace must be located or protected to avoid physical damage by vehicles.

?WARNING: This furnace is not to be used as a construction heater.

5. Listed below are definitions of "COMBUSTIBLE MATERIAL" and "NON-COMBUSTIBLE MATERIAL."
COMBUSTIBLE MATERIAL:
Material made of or surfaced with wood, compressed paper, plant fibers, plastics, or other material that will ignite
and burn, whether flame resistant or not.
NON-COMBUSTIBLE MATERIAL:
Material that is not capable of being ignited and burned. Such materials consist entirely of, or a combination of,
steel, iron, brick, tile, concrete, slate, or glass.
MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
TYPE OF UNIT

LOWBOYS

HIGHBOYS

COUNTERFLOWS

TYPE OF UNIT
HORIZONTALS2
Notes:

MODEL
NO.1

FROM SIDES
OF FURNACE

FRONT

OL2
OL5,11,16
OL20
OL33,37,39
OH3,11
OH5
OH16
OH2
OC2
OC5

1
1
1
1
1
1
1
1
1
1

2
24
24
24
24
24
24
Note3
4
4

TOP &
SIDES OF
PLENUM
1
1
1
1
1
1
1
2
1
1

REAR

BOTTOM

MODEL
NO.1

FRONT

TOP

OT5
24
1
1
1
OT11,16
24
1
1
1
1
The above are abbreviated model numbers.
2
Horizontal units are not approved for attic installation.
3
OH2 front clearance for 6 for Closet, 18 for Alcove.

FROM THE
FLUE/VENT

REAR

4
6
18
18
9
6
9
9
6
9

1
1
1
1
1
1
1
1
1
1

FROM THE
FLUE/VENT

ANY SIDE
OF
PLENUM
1
1

4
9

All installations and services must be performed by qualified service personnel.

The minimum clearances listed in the preceding table are for fire protection. Clearance for servicing the front of the
furnace and the rear of the lowboy models should be at least 24 inches. A clearance of 24 inches is recommended
for passage to all points on the furnace requiring service access.
The OH2-3-5-11-16 furnaces may be installed on combustible flooring. The OL2-5-11-16-20-33-37-39 and OC2-5
furnaces are to be installed on non-combustible flooring only. A non-combustible floor base is available for the
counterflow models OC2-5, which then allows these models to be adapted for installation on combustible flooring
(use non-combustible floor base Model No.125 for OC5, Model No 56 for OC2).
NOTE: The OH2 furnace is approved for closet installation. If the OH2 is installed in a closet, it requires two
openings in the closet door for combustion air, each having a minimum area of 162 sq. inches. This free area for the
OH2 intentionally exceeds the recommended minimum free area of 2 square inches per 1000 BTUH of input rate.
NOTE: When power venting a Thermo Pride oil fired furnace with a power venting system other than the system
supplied by Thermo Pride, a fiber chamber and an isolated combustion air kit (PVB or Beckett boot) is to be used
with the other manufacturers power venting system.
NOTE: On the front flue, lowboy, all highboy or counterflow models, it is possible to rotate the flue elbow (which is
factory installed for vertical discharge) 90 counterclockwise from the vertical position to adapt to various venting
systems. (See following page for details)

? CAUTION MUST BE TAKEN NOT TO EXCEED 90 ROTATION (OF THE FLUE

ELBOW) COUNTERCLOCKWISE OR RIGHT FROM THE VERTICAL POSITION.
ROTATION OF FRONT FLUE ELBOW
When an installation requires that the flue exit out the left hand side casing on a front flue unit, remove screw
securing the 90 deg. elbow and rotate it 90 counterclockwise. Then, by following dimensions in Table 1, locate the
center point for the exit of the flue for the particular size furnace. Once the center has been located, use a scribe to
mark the hole size, listed in the chart, which corresponds with the furnace being used. Cut hole out and extend flue
through side casing.
A trim collar may be ordered from Thermo Products to hide the gap around the flue pipe. This trim collar, however,
is not required for operation.

All installations and services must be performed by qualified service personnel.

NOTE: ROTATION OF FLUE PIPE IS ONLY ALLOWED FOR LEFT HAND SIDE VENTING
APPLICATIONS.
TABLE 1: Suggested sizes and positions of flue pipe opening on left hand side of casing.
UNIT

DIA. HOLE

X DIM.

Y DIM.

FLUE DIA.

TRIM COLLAR/
GASKET PART #

OC2
OC5
OH2
OH3
OH5
OH11
OH16
OL2*
OL5*
OL11*
OL16*
OL20*

5-1/2
6-1/2
5-1/2
6-1/2
6-1/2
6-1/2
7-1/2
5-1/2
6-1/2
6-1/2
7-1/2
7-1/2

3-5/8
4-3/4
3/5/8
4-9/16
4-3/4
4-3/4
4-5/16
3-5/8
4-5/8
4-1/2
4-1/2
4-1/2

28-3/8
31-7/16
28-3/8
32-3/16
33-1/16
35-1/4
41-3/8
28-5/16
34-15/16
37-5/8
39-1/8
43-1/4

5
6
5
6
6
6
7
5
6
6
7
7

14121/330073
14131/330005
14121/330073
14131/330005
14131/330005
14131/330005
14132/330006
14121/330073
14131/330005
14131/330005
14132/330006
14132/330006

* FRONT FLUE MODELS ONLY

X DIMENSION IS MEASURED FROM SEPARATOR PANEL.
Y DIMENSION IS MEASURED FROM THE BLOWER PAN ON H MODELS AND FROM THE BASE ON
L AND C MODELS.

Fig 1: Recommended location for drilling hole to connect

vent pipe to the furnace through the left hand side casing.
A. DRAFT REGULATORS:
A draft regulator is supplied with the furnace and should be installed according to the regulator manufacturers
recommendations. With the burner operating, use a draft gauge to adjust the regulator to the proper setting. (refer to
the instructions enclosed with draft regulator to adjust to the proper setting). When the burner air supply and draft are
properly adjusted, the overfire draft should be a negative (-).01" to (-).02" WC, as measured at the 5/16" overfire air
tap (See Fig. T). This tap is provided in the upper burner mounting plate. To measure the flue draft, punch a small
hole in the vent connector pipe as close to the furnace as possible and always before the draft regulator.
B. DUCT WORK/AIR CONDITIONING:
If the furnace is used in connection with summer air conditioning (cooling), the furnace should be installed parallel
with or on the upstream side of the evaporator coil to avoid condensation in the furnace heat exchanger. If the
cooling unit is installed with a parallel flow arrangement, dampers or other means used to control flow of air should
be provided to prevent chilled air from entering the furnace. If such a damper is manually operated, it must be
equipped with a means to prevent operation of either unit, unless the damper is in the full heat or cool position.

All installations and services must be performed by qualified service personnel.

The duct system should again follow the current design standard of Air Conditioning Contractors of America
(ACCA) or ASHRAE Fundamentals volume.
The most common location for the A-shaped coil (A style) is shown in Fig. 2.

Fig 2: Acceptable locations for the air conditioner evaporator coil.

NOTICE: The minimum coil pan clearance for a sectional or drum type heat exchanger is three inches unless
specified otherwise by the individual coil manufacturer.
A slab coil (H-style) is available for the horizontal air flow application on the OT5-11-16 furnaces refer to Fig. 3.

Fig. 3: An acceptable location for the air conditioner evaporator coil when used with a horizontal furnace.
To obtain proper airflow with an air conditioning coil installed on a belt drive unit, the motor and/or blower pulley
may need to be changed. On a direct drive unit, the blower motor speed may need to be changed depending upon the
size of the air conditioning system installed and the airflow resistance of the duct system.
NOTE: The horizontal units have direct drive blowers and no pulley or motor change is required.
C. FILTERS MOUNTED EXTERNAL TO THE FURNACE:
The filters of the OC2-5 mount in the return air plenum on the top opening on the top of the furnace. (For
installation detail, see figure 4).

Fig. 4: Air filter mounting location for the OC2-5 furnace.

All installations and services must be performed by qualified service personnel.

On highboy furnaces, it is necessary to cut the return air opening in the side or rear casing, depending upon the
needs of the specific installation.
The filter rack provided with the furnace, refer to Fig. 5, will serve as a template to scribe a mark for the return air
opening on the casing. Place the filter rack on the casing one inch up from the bottom of the furnace and centered
from side to side. Place the securing flange against the casing when locating the return air opening.

Fig. 5: A typical filter rack and dimensions for the highboy furnaces.
PLEASE NOTE: While scribing the return air opening, the filter rack can be held in position by tape or similar
temporary means.
Position the open end of the filter rack so as to provide access for filter replacement. Once the filter rack is
positioned correctly, scribe a line along the inside of the securing flange on three of the sides. To scribe a line on the
fourth side (the open end), use the open end support as a guide.
Remove the filter rack and cut the return air opening in the casing. Now the filter rack can be anchored to the furnace
with screws or pop-rivets through the securing flange of the filter rack.

?WARNING: When cutting openings in the casing DO NOT CUT ANY SUPPORTING
CLIPS OR ANGLES. Cut as close to the scribed line as possible, but do not cut the base clip or
blower pan support angle. (See Fig. 6).

Fig. 6: Cutaway view of fan section of a typical highboy furnace.

Connect the return air plenum to the filter rack and slide the filter into place. Dimensions for adapting the return air
plenum to the filter rack are provided on the bottom of the previous page.

All installations and services must be performed by qualified service personnel.

D. FAN AND LIMIT POSITION AND LOCATION

?WARNING: The predetermined fan and limit locations on all of the Thermo Pride oil fired
furnaces have been tested and approved by Thermo Products, LLC. in conjunction with
Underwriters Laboratories, Inc. Any attempt to relocate these safety controls or replace these
safety controls with a control that is not approved, or is incompatible, may result in personal
injury, substantial property damage or death.
The units listed in the table below must have the fan and limit control installed at the time of unit installation. A
locating bracket is provided with each of the units below.

TABLE 2: Installation location of

the fan and limit control for each
furnace

Fig. 7: Fan and limit location for lowboys, horizontal units and highboys.
FAN & LIMIT LOCATION FOR HORIZONTAL UNITS WITH AIR CONDITIONING COIL:
The fan & limit control should be mounted between the H-coil cabinet and furnace. For distances from top of plenum
and furnace, see Fig. 7. IMPORTANT: Do not try to mount fan/limit in H-coil cabinet.
NOTE: The OL2, OC2 and OH2 only, come standard with an oil filter packaged with the furnace. This filter has the
capacity of filtering down to a 10 micron particle. This is to assure the small diameter burner nozzles in the low
heating capacity furnaces are installed with a fine filter to help prevent nozzle clogging.
E. BURNER INSTALLATION:
NOTICE: Remove all cardboard packing from around chamber before installing burner.

All installations and services must be performed by qualified service personnel.

The oil burner will mount on three stud mounting bolts on the lower mounting plate covering the opening in the front
of the heat exchanger. The end of the burner tube should be inserted no further than 1/4 inch back from the inside
surface of the combustion chamber. A distance further than 1/4 inch back from the inside chamber wall may cause
impingement and sooting.
NOTE: OVERFIRE AIR TAP MAY BE LOCATED ON EITHER SIDE OF FLAME INSPECTION
COVER. (See Fig. 8).
TWO PIECE MOUNTING PLATE

Fig. 8: Typical location of the overfire air tap

Fig. 9: (Top view) Burner insertion illustration

When mounting the burner, the upper mounting plate (Fig. 8) must be removed to provide access to the area in front
of the combustion chamber. The combustion chamber can then be moved forward or backward slightly to allow for
adjustment in positioning the burner tube. A fiber insulating sleeve or amulet is provided on the burner tube of
specific Thermo Pride burners.(see Fig. 10). See Thermo Pride burner application chart for type of insulator. Do not
allow the burner tube or end cone to physically touch or protrude into the chamber, as excess heat transfer could
result in destruction of the tube, end cone or both. The burner tube/end cone is properly positioned, when the end is
inch back from the inside surface of the combustion chamber wall.
NOTE: The OL2, OC2 and OH2-56 furnace models have two chamber positioning clips on the pouch bottom to
prevent the chamber from being pulled forward too close to the mounting plate and burner. If the chamber is pulled
back against these clips the insertion depth should be correct. The loose-fill insulation that is included in a brown
paper bag should be lightly placed around the burner tube between the front of the combustion chamber and the
burner mounting plate. (DO NOT PACK THE INSULATION DOWN). The loose-fill insulation should be placed
in such a fashion that the surface of the insulation is sloped from the top of the combustion chamber to the top of the
lower mounting plate. The purpose of the loose insulation is to help protect the burner tube, mounting plates and
vestibule area from excessive temperatures.
On the horizontal units, the loose-fill insulation will fall down around the side of the chamber (the chamber is on its
side in horizontal units). This presents no problem to the unit, as the amount of insulation under the side will be
minimal, but take care not to allow the insulation to fall into the open end of the chamber where it may burn and
blow around, possibly lodging in the burner.
NOTE: Do not place loose insulation around chamber sides and back except for the larger units (Models OL33, 37
and 39) where the loose insulation is to be used around rear of chamber to ensure chamber stability. See larger
unit assembly instructions for further details. (See Fig. 9).

All installations and services must be performed by qualified service personnel.

Fig. 10: (Side view) Burner insertion illustration

F. HORIZONTAL FURNACE POSITIONS:
The horizontal furnace may be turned end for end, or rotated, making the top into the bottom, as shown in Fig. 11.

Fig. 11: A horizontal furnace rotated 180 (or flipped end for end) to reverse airflow direction
After the furnace has been positioned, the bottom burner mounting stud must be broken off before mounting the
burner (See Fig. 12). Also, the fan & limit and its mounting bracket must be relocated once the unit is in position.
(See Fig. 7).

Fig. 12: Required modification to burner mounting studs before burner installation
G. EXTERNAL WIRE HARNESS LOCATIONS FOR OL33, 37

Fig. 13: External electrical wiring in conduit on large furnace models

8

All installations and services must be performed by qualified service personnel.

The OL33, 37 and 39 furnaces have an external wire harness that mounts in pre-punched holes in the side casings
(See Fig. 13).
A Horizontal furnace is shown below with external wire harness and fan speed terminal strip (blower access panel
removed). (See Fig. 14).

Fig. 14: The wiring system of a typical horizontal furnace

H. BURNER SPECIFICATIONS AND APPLICATIONS

THERMO PRIDE BURNER APPLICATIONS

THERMO
PRIDES
BURNER
SPEC NO.

*
INS

OC2-56

TP-1401

OC5-85

TP-101

OH2-56
OH3-72
OH5-85
OH11-105
OH16-125

TP-1401
TP-101
TP-101
TP-101
TP-102

OL2-56
OL5-85
OL11-105
OL16-125
OL20-151
OL33-200
OL37-250
OL39-320
OT5-85
OT11-105
OT16-125

FURNACE
MODEL

BECKETT
BURNER
MODEL &
TUBE
LENGTH
AFG-3-5/8

HEAD

STATIC
PLATE

MAXIMUM
NOZZLE
SIZE**

STANDARD
NOZZLE
SIZE

OIL
PUMP
PRESSURE
(PSIG)

FO

3-3/8

0.55X70H

0.50X70H

120

AF 7-3/4

F3

2-3/4

0.75X80H

0.75X80H

100

N
S
S
S
S

AFG 3-5/8
AF 7-3/4
AF 7-3/4
AF 7-3/4
AF 7-3/4

F0
F3
F3
F3
F6

3-3/8
2-3/4
2-3/4
2-3/4
2-3/4

0.55X70H
0.65X80H
0.75X80H
0.90X80H
1.25X80H

0.50X70H
0.65X80H
0.75X80H
0.90X80H
1.10X80H

120
100
100
100
100

TP-1401
TP-101
TP-101
TP-102
TP-1003
TP-104
TP-105
TP-106

N
S
S
S
S
S
N
N

AFG 3-5/8
AF 7-3/4
AF 7-3/4
AF 7-3/4
AF 7-3/4
AF 5-3/4
AF 5-3/4
AF 5-3/4

F0
F3
F3
F6
F12
F22
F31
F31

3-3/8
2-3/4
2-3/4
2-3/4
2-3/4
2-3/4
2-3/4
SPIDER

0.55X70H
0.75X80H
0.90X80H
1.25X80H
1.35X80S
2.00X80S
2.50X80S
3.00X80S

0.50X70H
0.75X80H
0.90X80H
1.10X80H
1.35X80S
1.75X80S
2.25X80S
2.75X80S

120
100
100
100
100
100
100
100

TP-101
TP-101
TP-102

S
S
S

AF 7-3/4
AF 7-3/4
AF 7-3/4

F3
F3
F6

2-3/4
2-3/4
2-3/4

0.75X80H
0.90X80H
1.25X80H

0.75X80H
0.90X80H
1.10X80H

100
100
100

* INSULATOR S = SLEEVE OR N = NONE

** MAXIMUM NOZZLE SIZE FOR UL LISTING OF FURNACE. THE NOZZLE SIZE GIVES THE
NOMINAL FLOWRATE, IN GPH, FOLLOWED BY THE SPRAY ANGLE, IN DEGREES, AND THE
SPRAY PATTERN, EITHER H FOR HOLLOW CONE OR S FOR SOLID CONE. FOR EXAMPLE, A
NOZZLE RATED AT 0.65 GPH @ 100 PSIG THAT PROVIDES AN 80 SPRAY ANGLE AND A
HOLLOW SPRAY PATTERN WOULD BE ABBREVIATED IN THE TABLE AS 0.65 X 80H.
For more specific burner information, contact Thermo Products, LLC. P.O. Box 217, North Judson, IN 46366.
Phone 574-896-2133.
9

All installations and services must be performed by qualified service personnel.

STANDARD BURNER NOZZLES: The OL2, OH2, OC2 and OC1, along with the OL33, OL37 and OL39 have
the nozzles already installed in the burners. The balance of the oil units has the nozzles shipped as loose items with
the furnace. Below is a chart showing the heating capacity of the furnace for each approved nozzle size.

OIL NOZZLE CAPACITY CHART

EQUIVALENT
HEAT
INPUT RATE*
(BTU/HR)

UNITS

EFFECTIVE
HEATING
CAPACITY**
(BTU/HR)

NOZZLE SIZE
(GPH)
__________________________________________________________________________________________
OH2,OL2,OC2
.50
70,000
56,000
.55
77,000
61,600
OH3

.65

91,000

72,800

OL,OH,OC,OT5

.75

106,250

85,000

OC5

.85

119,000

95,200

OL, OT11

.85
.90

119,000
126,000

95,200
100,800

OH11

1.00

140,000

112,000

OH,OL,OT16

1.10
1.20
1.25

154,000
168,000
175,000

123,200
134,400
140,000

OL20

1.35

189.000

151,200

OL33

1.75
2.00

245,000
280,000

196,000
224,000

OL37

2.25
2.50

315,000
350,000

252,000
280,000

OL39

2.75
3.00

385,000
420,000

308,000
336,000

All rates shown above achieved with 100 PSIG pump pressure (except for OH2, OL2 and OC2, which require 120
PSIG).
* Based on #2 domestic heating fuel oil having heating value of 140,000 BTU per gallon.
** Based on thermal efficiency of 80%.

10

All installations and services must be performed by qualified service personnel.

RIELLO BURNER APPLICATION CHART
The optional F3 and F5 Riello flame retention oil burners have been UL listed (UL File #MP3252) for application on
the following Thermo Pride oil fired furnaces.
OH3

OC5, OL5,
OH5, OT5

OL11, OH11,
OT11

OL16, OH16,
OT16

TOP-25752
BTM-35733

35750

35750

35750

MTG. PLATE
GASKET
PART NO.

330090

330088

330088

330088

330088

**NOZZLE
SIZE

.50-60A

.60-60A*

.75-60A*

.90-60A*

1.10-60A*

NOZZLE
PART NO.

380393

380394

380395

380396

380397

170 PSI

145 PSI

145PSI

145 PSI

150PSI

F3

F3

F5

F5

F5

380215

380215

380216

380216

380216

MODEL
PART
MTG. PLATE
PART NO.

OIL PUMP
PRESSURE
BURNER
BURNER
PART NO.

OL20
35750

* A refers to hollow pattern nozzle

** NOTE: The reason the Riello burner nozzle sizes are smaller than the standard Thermo Pride burner nozzles is
that pre-set pump pressures are higher, therefore achieving the same firing rate with a smaller nozzle.
For more specific burner information, specifications or service information, reference the training manual enclosed
with each Riello burner or contact:
Riello Corporation of America,
5 Pond Park Road
Hingham, Massachusetts 02043
(617) 749-8292
I. HEAT EXCHANGER CLEANING INSTRUCTIONS:

?WARNING: THE HEAT EXCHANGER MUST BE CLEANED BY A QUALIFIED

SERVICE PERSON.
It is important to inspect and clean the heat exchanger once a year, or as necessary, to remove any build-up of soot.
A layer of soot on the inside of the heat exchanger will act as an insulator and reduce heat transfer, resulting in less
efficiency.
To clean the heat exchanger, first turn off all power to the unit. Next, remove the access panel (see below and
beginning of following page) immediately above the burner (on the horizontal furnace, it will be located to the side
of the burner) to gain entry to the clean-out covers, refer to figure 15. This panel is identified with a label. Remove
clean-out covers, the vent connector pipe to the chimney, the burner, and the burner mounting plates. When
removing the clean-out covers, special care must be taken not to damage the gaskets. Should the gaskets separate,
crack, break, or be unsuitable for reuse, the gasket must be replaced before reattaching the clean-out covers.

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All installations and services must be performed by qualified service personnel.

Fig. 15: Typical Heat Exchanger Cleanout Cover Locations.

With access to the inside of the heat exchanger through the burner area, clean-out openings, and vent pipe
connection, it is possible to use a long, flexible wire brush and an industrial type vacuum cleaner to remove any soot
build-up. NOTE: A one inch (outside diameter) vacuum cleaner hose will fit into the radiator.
To vacuum and brush the outer radiator of the heat exchanger, go through the clean-out openings in both directions,
as shown in figure 16, below.

Fig. 16: Recommended method and device for cleaning inside of heat exchanger.
Reassemble the furnace to its original construction. Remount the burner being certain that the air tube is properly
inserted into the chamber opening (see section E). If heavy soot deposits were found in the heat exchanger, this may
indicate the burner is out of adjustment.

III. USERS INFORMATION SECTION

A. OIL SUPPLY: Do not allow the fuel tank to run completely empty. During the summer, keep the tank full to
prevent condensation of moisture on the inside surface of the tank. If the fuel tank runs completely dry, it may be
necessary to purge the lines of trapped air. Contact a qualified technician to bleed the lines and restart the burner.
OIL SUPPLY VALVE: Turn the oil supply valve off if the burner is shut down for an extended period of time.
B. COMBUSTION AIR SUPPLY: The burner requires a generous amount of clean combustion air to operate
safely. Lack of adequate combustion air can result in erratic operation of the burner, noisy combustion, or fuel odors
in the air. NEVER BLOCK THE FURNACE FROM THE SUPPLY OF COMBUSTION AIR. If there is an exhaust
fan, dryer or return air grill in the furnace room, there should be increased concern and additional efforts may be
required to provide adequate combustion oil to the furnace at all times.
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All installations and services must be performed by qualified service personnel.

C. INSPECTION AREAS
VESTIBULE: The furnace vestibule area or burner compartment should be inspected by removing the front door of
the furnace and looking for signs of excessive heat such as discoloration of components materials damage, from rust
or corrosion, soot or carbon build-up.
EXTERIOR OF FURNACE: The furnace exterior should be inspected for signs of excessive heat such as
discoloration of materials and damage from rust or corrosion.
FLUE PIPE, VENT PIPE OR CONNECTOR: The furnace vent pipe should be inspected for signs of rust,
corrosion pitting or holes in pipe, and leakage around seams in pipe, indicated by soot or condensate streaks.
CHIMNEY OR VENTING SYSTEM: The furnace venting system should be inspected for signs of rust, corrosion
pitting or holes, and signs of condensation or moisture leakage from the venting system.
If any of the above symptoms are evident, call a qualified heating contractor for assistance.

?CAUTION: DO NOT ATTEMPT TO MAKE REPAIRS YOURSELF!

?WARNING: The area around the furnace should be kept free and clear of combustible
liquids and material, especially papers and rags.
?WARNING: NEVER burn garbage or refuse in your furnace. Never try to ignite oil by
tossing burning papers or other material into your furnace.
?WARNING: Thermo Pride oil furnaces are designed to burn No. 1 or No. 2 distilate fuel
oil. NEVER USE GASOLINE OR A MIXTURE OF OIL AND GASOLINE.
?CAUTION: DO NOT ATTEMPT TO START THE BURNER WHEN:
1. Excess oil has accumulated,
2. The furnace is full of vapors
3. The combustion chamber is very hot.
IF ONE OR MORE OF THESE CONDITIONS EXIST, CONTACT A QUALIFIED
SERVICE PERSON.
D. STARTING THE BURNER:
1. Turn the main service switch to "OFF" position.
2. Set thermostat substantially above room temperature.
3. Open shut-off valves in oil supply line to burner.
4. Turn service switch to furnace "ON". If burner starts and runs, but stops again on lockout, it may be necessary to
bleed the lines or make burner combustion air adjustments. Contact a qualified service person to adjust and start
burner.
E. FILTER CLEANING AND LOCATION:
The air filters should be inspected each month and cleaned when dirty. Cleaning the air filters frequently may reduce
airborne contaminants from entering the furnace and depositing in the furnace, duct system and home.

?WARNING: To avoid injury from moving parts, hot surfaces, or electrical shock, shut
off the power to the furnace before removing any furnace access doors to service the air
filters.
OL Series (Lowboy)
To clean a dirty filter, first remove the blower compartment door at the rear of the furnace, refer to figure
17. Remove the dirty filter from the filter rack and clean it with a mild soap and water solution. Make sure filter is
thoroughly dry before replacing. Replace the blower compartment door.
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All installations and services must be performed by qualified service personnel.

Fig. 17: Location of the air filter and blower compartment access door on the typical lowboy furnace.
OH Series (Highboy)
The filter rack will be located between the return air plenum and the return air opening on the side of the
furnace, refer to figure 18. Slide the dirty filter out, clean it with a mild soap and water solution. Make sure filter is
thoroughly dry before replacing.

Fig. 18: Location of the air filter on the typical highboy furnace.
OC Series (Counterflow)
For removal of the filter, remove front door of furnace. Then, remove blower access panel for access to
filter, refer to figure 19. Clean filter by vacuuming, tap-water rinsing or washing in an ordinary detergent soloution.
After cleaning, replace the completely dry filter mesh side down.

Fig. 19: location of the air filters on a typical counterflow furnace.

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All installations and services must be performed by qualified service personnel.

COMBUSTION AND EFFICIENCY TESTING FOR THERMO PRIDE
OIL FIRED CENTRAL FURNACES.
Complete this form for each Thermo Pride furnace installed. Read instruction
manual carefully before making tests. Retain this form with furnace.
CUSTOMER

NAME
ADDRESS
CITY, STATE

HEATING

BURNER MODEL NO.

AIR SHUTTER OPENING

BLAST TUBE LGTH.

INS.

SYSTEM
COMBUSTION CHAMBER

CONDITION

% OF MAX. (EST)

MATERIAL

FURNACE MODEL

TYPE OF VENTING SYSTEM

MASONRY
CHIMNEY

METAL
CHIMNEY

SIDEWALL
POWER VENTER

METAL
CHIMNEY

MASONRY CHIMNEY
W/METAL LINER

MASONRY
CHIMNEY
W/INDUCER

W/INDUCER
FUEL LINE FILTER

DRAFT CONTROL

INITIAL
INSTALLATION

COMBUSTION
TESTS
(Operate burner
at least 10
minutes before
starting tests.)

CO2 in stack pipe

Draft Over-fire
Draft in stack pipe
Smoke number
Gross stack temp.
Furnace room temp.
Net stack temp.
(Gross stack minus
furnace room temp.)
Efficiency
Nozzle size and spray
Oil pump pressure
Operation of Controls
Burner Safety Controls
Check for oil leaks
Tests taken by
Date
NOTES:

INSTALLER NAME & ADDRESS

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FURNACE SERIAL NUMBER

SERVICE

SERVICE

SERVICE

All installations and services must be performed by qualified service personnel.

APPENDIX-A Replacement Parts List

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All installations and services must be performed by qualified service personnel.

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All installations and services must be performed by qualified service personnel.

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All installations and services must be performed by qualified service personnel.

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All installations and services must be performed by qualified service personnel.

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All installations and services must be performed by qualified service personnel.

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All installations and services must be performed by qualified service personnel.

APPENDIX-B Wiring Diagrams

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