Thermo Pride OL6FA072D48B Owner's manual

MO-547
ECN 5539-MA 200902 Made IN USA
OIL FIRED FURNACE
INSTALLATION AND OPERATION MANUAL
WITH USERS INFORMATION SECTION
MODELS:
OL6FA072D48(B/R/C) OL6RA072D48(B/R/C)
OL6FA072DV5(B/R/C) OL6RA072DV5(B/R/C)
OL8FA 9T60(B/R/C) OL8RA 9T60(B/R/C)
c 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.
c 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.
c AVERTISSEMENT: SI L'INFORMATION DANS CES INSTRUCTIONS N'EST PAS SUIVI À LA LETTRE, UN
INCENDIE OU UNE EXPLOSION ENTRAÎNANT DES DOMMAGES MATÉRIELS, DES BLESSURES CORPORELLES
OU DES PERTES DE VIE.
NE PAS ENTREPOSER NI UTILISER D'ESSENCE OU AUTRES VAPEURS ET LIQUIDES INFLAMMABLES À
PROXIMITÉ DE CET APPAREIL OU DE TOUT AUTRE APPAREIL.
c AVERTISSEMENT: UNE MAUVAISE INSTALLATION, D'AJUSTEMENT, DE LA MODIFICATION,
D'ENTRETIEN OU DE MAINTENANCE PEUVENT CAUSER DES BLESSURES OU DOMMAGES MATÉRIELS,
REPORTE -VOUS À CE MANUEL POUR OBTENIR DE L'AIDE OU DES RENSEIGNEMENTS SUPPLÉMENTAIRES,
CONSULTER UN INSTALLATEUR QUALIFIÉ, OU ORGANISME DE SERVICE.
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.
VEUILLEZ LIRE CES INSTRUCTIONS AVANT L'INSTALLATION, LES PREMIERS TIRS, ET AVANT
D'EFFECTUER TOUT ENTRETIEN OU MAINTENANCE. CES INSTRUCTIONS DOIVENT ÊTRE LAISSÉS
AVEC L'UTILISATEUR ET DEVRAIT ÊTRE CONSERVÉ POUR RÉFÉRENCE FUTURE PAR UN TECHNICIEN
QUALIFIÉ.
THERMO PRODUCTS, LLC.
PO BOX 237
DENTON, NC 27239
PHONE: [phone]
(OL6 SERIES) (OL8 SERIES)

All installations and services must be performed by qualified service personnel.
i
I. SAFETY SECTION
This page contains various warnings and cautions found throughout the Oil
Furnace Manual. Please read and comply with the statements below.
c
WARNING AND CAUTIONS:
cWARNING: This furnace is not to be used as a construction heater. See Page .
c
CAUTION MUST BE TAKEN NOT TO EXCEED 90° ROTATION (OF
THE FLUE ELBOW) COUNTERCLOCKWISE OR RIGHT FROM THE
VERTICAL POSITION.
cWARNING: The predetermined limit location on this oil fired furnace has
been tested and approved by Thermo Products, LLC. Any attempt to relocate
this safety control or replace this safety control with a control that is not
approved, or is incompatible, may result in personal injury, substantial property
damage or death.
cWARNING: THE HEAT EXCHANGER MUST BE CLEANED BY A
QUALIFIED SERVICE PERSON.
cCAUTION: DO NOT ATTEMPT TO MAKE REPAIRS YOURSELF!
cWARNING: The area around the furnace should be kept free and
clear of combustible liquids and material, especially papers and rags.
cWARNING: NEVER burn garbage or refuse in your furnace. Never try
to ignite oil by tossing burning papers or other material into your furnace.
cWARNING: This oil furnace is designed to burn No. , No. 2, or B5 distillate
fuel oil. NEVER USE GASOLINE OR A MIXTURE OF OIL AND GASOLINE.
cCAUTION: DO NOT ATTEMPT TO START THE BURNER WHEN:
Excess oil has accumulated,
. The furnace is full of vapors
2. The combustion chamber is very hot.
IF ONE OR MORE OF THESE CONDITIONS EXIST, CONTACT A
QUALIFIED SERVICE PERSON. See Page 20.

ii
All installations and services must be performed by qualified service personnel.
For additional Oil Heating assistance:
Scan the QR code to view Thermo Product’s
Oil Heating Installation, Maintenance Service Manual
TABLE OF CONTENTS
SECTION
BEGINNING
PAGE
I. SAFETY SECTION i
II. GENERAL INSTRUCTIONS 1
A. VENTING 3
B. DRAFT REGULATORS 3
C. DUCT WORK/AIR CONDITIONING/SUPPLY/RETURN
AIRFLOW AND AIR TEMPERATURE 5
D. AIR FILTERS 6
E. LIMIT POSITION 7
F. BURNER INSTALLATION 7
G. BURNER SPECIFICATIONS AND APPLICATIONS 9
H. HEAT EXCHANGER CLEANING INSTRUCTIONS 11
I. FAN CONTROL BOARDS 12
III. USERS INFORMATION SECTION 19
A. OIL SUPPLY 19
B. COMBUSTION AIR SUPPLY 19
C. INSPECTION AREAS 19
D. STARTING THE BURNER 20
E. FILTER CLEANING AND LOCATIONS 20
APPENDIX – A REPLACEMENT PARTS LIST 22
APPENDIX – B WIRING DIAGRAMS 36
APPENDIX – C AIRFLOW CHARTS 42

All installations and services must be performed by qualified service personnel.
1
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. It is recommended that a commercially available CO alarm be installed in
conjunction with any fossil fuel burning appliance. The CO alarm shall be installed according to
the alarm manufacturer’s installation instructions and be listed in accordance with latest edition
of the UL Standard for Single and Multiple Station Carbon Monoxide Alarms, UL 2034, or the
CSA International Standard, Residential Carbon Monoxide Alarming Devices, CSA6.19.
cWARNING: This unit is not to be used for temporary heating of buildings, or structures,
under construction.
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.

All installations and services must be performed by qualified service personnel.
2
Table : MINIMUM CLEARANCES TO COMBUSTIBLE MATERIALS
TYPE
OF
UNIT
MODEL NO. FROM
SIDES OF
FURNACE
FRONT TOP &
SIDES
OF
PLENUM
FROM
THE
FLUE/VEN
T
REA
R
Lowboy OL6**072D*** 0” 6” ‡ 1” 7” 0” ‡
Lowboy OL8**119T60* 0” 6” ‡ 1” 8” 0” ‡
‡ The minimum clearances listed in the preceding table are for fire protection. Clearance for
servicing the front and rear of the furnace should be at least 24 inches.
NOTE: The OL6 & OL8 furnace are approved for closet installation. If the furnace is
installed in a closet, it requires two openings in the closet door for combustion air,
each having a minimum area of 181 sq. Inches. This free area intentionally exceeds
the recommended minimum free area of 1 square inch per 1000 BTUH of input rate.
Chimney Inspection
The chimney, vent, or any passageway for the stack gases to flow to the outdoor atmosphere is a
very important part of the heating system. No furnace, regardless of the efficiency of the design, can
perform satisfactorily when the chimney to which it is connected is inadequate or in poor condition.
Any of the following symptoms may indicate a chimney has severe structural damage and is
unsuitable for use.
 Chimney appears to be leaning to the side.
 Chimney appears to have structural damage, i.e. loose or missing blocks or bricks, or excessive
deterioration at mortar joints.
 Tile liner damaged or missing.
 Flue gas leakage along the length of the chimney between the chimney connector and discharge
termination.
 Excessive corrosion at the cleanout port or at the chimney connector entrance into the chimney.
 Structural debris, i.e. mortar or tile liner flakes, in base of the flue way.
A qualified person shall inspect the chimney to confirm it is correctly sized for the application,
properly constructed, and in sound condition. Refer to the Standard for the Installation of Oil-
Burning Equipment, NFPA 31-2001, for details on proper chimney sizing and construction. If
needed, the chimney should be cleaned before installing the furnace. Any accumulation of dirt or
debris at the bottom of the flue should be removed.

All installations and services must be performed by qualified service personnel.
3
A. FLUE / CHIMNEY / VENT CONNECTOR
c CAUTION:
 DO NOT install a manual damper in the chimney or vent connector.
 Thermally- activated type vent dampers are NOT recommended for use on these furnaces.
It is desirable to install the shortest vent connector (also referred to as a flue or chimney connector)
possible with the fewest number of fittings, i.e. transitions and elbows. Generally, 6-inch diameter,
24 Ga. or heavier, single wall, lock seam-type, galvanized steel vent pipe and fittings are
satisfactory materials for the fabrication of a vent connector. However, always consult local codes
and authorities for specific minimum requirements.
For some installations, it may be prudent to turn the furnace flue elbow 90 degrees clockwise, with
respect to the front of the furnace, such that the elbow is open to the right-hand side of the unit,
rather than upward. Turning the flue elbow may better facilitate connection of the vent connector
piping to the flue elbow on the highboy and front flue, lowboy furnaces. Due to the presence of the
limit control and the wiring harness, the elbow may not be rotated 90 degrees counterclockwise.
The installer must carefully mark and cut a hole in the furnace housing to allow the vent connector
to pass through the housing.
If desired, with the furnace flue elbow turned to the right, the standard furnace top front panel (p/n
17346-2) may be replaced with the top front panel from the rear flue lowboy model (p/n 17383-2).
Refer to Appendix D: Replacement Parts for sketches of these parts. Contact your distributor to
purchase this part.
All horizontal sections of the vent connector must slope upward not less than ¼ inch per foot
from the furnace to the vent termination. Long horizontal sections of the venting system must be
supported at least every five (5) feet with metal straps to prevent sagging of the vent piping.
Secure all joints in the vent connector with sheet metal screws or equivalent fasteners. Vent
piping must not be inserted beyond the inside wall of the chimney flue.
B. DRAFT REGULATOR
A barometric-type, draft regulator is supplied with the furnace. Installation or operating
conditions that produce excess amounts of draft can reduce the heating efficiency of the furnace.
The purpose of the regulator is to adjust and control the flow of flue gases from the furnace by
stabilizing the amount of chimney draft to which the furnace is subjected.
Generally, install the barometric draft regulator in the vent connector as close as possible to the
flue outlet collar of the furnace. However, always refer to the draft regulator manufacturer’s
installation instructions for application specific recommendations.

All installations and services must be performed by qualified service personnel.
4
Direct (Side-Wall) Venting
The furnace may also be horizontally vented through a sidewall. Thermo Products has available
the side wall vent kits for such applications. When installing the sidewall vent kits, outside
combustion air must also be applied to the burner. The following table identifies application
order information.
Table 2: Sidewall vent kits
The vent may be installed either through the knock-out on the right or left side casing of the unit
or vertically out the top opening of the vestibule.
The combustion air inlet can be installed through the either the lower left side casing knockout or
the lower right side casing knockout.
Power (Side-Wall) Venting – Important Note Regarding
cCAUTION: Thermo Products, LLC will NOT assume responsibility for damage to, and
deterioration of, exterior building materials, e.g. brick, siding, clapboards, and etc., in close
proximity to the vent terminal due to operation of a power vented, oil furnace. This policy
is applicable regardless of the cause of sooting.
Two (2) problems typically arise when power venting any oil-fired appliance.
1) Soot buildup may occur at an accelerated rate on critical components of the furnace oil
burner, e.g. the primary control flame sensor (“cad cell”), the burner head, and oil nozzle.
2) Severe damage may occur to external surfaces of the structure in the event the furnace
continually produces a high level of smoke in the flue gases. Excess smoke and soot can be
produced for many reasons, some of which cannot be successfully controlled by the installer
and the appliance manufacturer.
NOTICE: Thermo Products recommends the use of a chimney to vent residential oil
furnaces. If a power venter must be used, it is the responsibility of the installer and power
venter manufacturer to design, assemble, and demonstrate proper operation of the power
venting system with the furnace.
FIELD VENT TERMINATION
KIT
SIDE WALL VENT
ACCESSORIES KIT
COMBUSTION AIR INTAKE
HOOD KIT
(15’ applicatio MAX) (BURNER SPECIFIC)
(FOR COMBUSTION AIR
APPLICATIONS ONLY)
THERMO PRODUCTS PART
NUMBER
THERMO PRODUCTS
PART NUMBER
THERMO PRODUCTS PART
NUMBER
(OL6) (OL8)
Beckett AFG AOPS8393 AOPS8414 AOPS8394 AOPS8397
iello BF5 AOPS8393 AOPS8414 AOPS8395 AOPS8416
Carlin EZ-1HP N/A AOPS8414 AOPS8432 AOPS8433
BURNER

All installations and services must be performed by qualified service personnel.
5
C. DUCT WORK/AIR CONDITIONING/SUPPLY/RETURN AIRFLOW AND AIR
TEMPERATURE:
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.
The supply/return airflow shall be set to obtain an air temperature rise, across the furnace, in the
range of 55º to 85ºF. Since the flow resistance of each duct system is slightly different, the
airflow (fan speed) may have to be changed in the field to achieve a satisfactory temperature rise.
One way to measure the temperature rise across the furnace is to insert temperature measuring
devices (e.g. thermometers) into the return air duct and into the supply air duct about 12 inches
from the furnace. After the furnace has been firing continually for over 20 minutes, read the
temperature difference between the two (2) thermometers. The temperature difference should
not exceed 85ºF, nor be less than 55ºF. A temperature rise of 70ºF is considered to be optimum
for comfort.
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. 1.
Fig : Acceptable locations for the air conditioner evaporator coil.

All installations and services must be performed by qualified service personnel.
6
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.
NOTICE: The minimum return air temperature is 55° F.
D. AIR FILTERS MOUNTED INTERNAL TO FURNACE:
Fig. 2: Internal filter rack.
cCAUTION: Failure to comply with minimum filter installation requirements may affect
the performance and/or void the warranty on this unit.
If a method other than internal Thermo Pride filter rack is selected for retention of the filters
and/or use of a different filter type is desired, refer to Table 4 below for minimum sizing
guidelines for selecting filter for the unit.
Filter Type
Maximum
Air Velocity
(ft/min)
Model Number
OL6
OL8
Qty
*Thermo Products
Supplied Permanent
600
280 in² 480 in² 2
Standard
Permanent
500
576 in² 576 in² 2
Disposable
300
960 in² 960 in² 2
Table 3: Minimum Required Filter Area (in square inches)
* The Thermo Products supplied filter can be cut to size to fit other filter retention systems
as long as the minimum size requirement is met.

All installations and services must be performed by qualified service personnel.
7
NOTICE: Any internal stiffeners used in the filter must not be removed, although they can
be cut to size as needed.
E. LIMIT POSITION
The limit in these furnaces are fixed and cannot be relocated.
F. BURNER INSTALLATION:
NOTICE: Remove all cardboard packing from around chamber before installing burner.
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. This unit
is equipped with a chamber retainer (refer to Fig.3). The retainer secures the chamber during
shipping and helps to maintain insertion depth.
DO NOT remove this retainer when installing burner.
Fig. 3: Typical location of the over fire air tap and components in burner mounting plate
area

All installations and services must be performed by qualified service personnel.
8
Fig. 4: Burner insertion illustration (Top view)
When mounting the burner, the mounting plate (Fig. 3) must be removed to provide access to the
area in front of the combustion chamber. A fiber insulating sleeve or amulet is provided on the
burner tube of
specific Thermo Pride burners.(see Fig. 4). 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 ¼ inch back from the inside surface
of the combustion chamber wall.
DO NOT CHANGE POSITION OF THE CHAMBER!

All installations and services must be performed by qualified service personnel.
9
G. BURNER SPECIFICATIONS AND APPLICATIONS:
Beckett oil burner application
FURNACE
MODEL
THERMO
PRIDE’S
BURNER
SPEC NO.
*
INS
BECKETT
BURNER
MODEL &
TUBE
LENGTH
HEAD
STATIC
PLATE
MAXIMUM
NO LE
SI E**
SHIPPED
NO LE
SI E
OIL PUMP
PRESSURE
(PSIG)
OL6*A072D**B TP2501
N
AFG-4.5” F3 3-5/8 0.75X70° B 0.60X70° B 120
OL8*A119T**B TP2502
N
AFG-4.5” F6 2-3/4U 1.10X80° A 1.00X80° A 120
Carlin oil burner application
FURNACE
MODEL
THERMO
PRIDE’S
BURNER
SPEC NO.
INS
+
CARLIN
BURNER
MODEL &
TUBE
LENGTH
HEAD
STATIC
PLATE
MAXIMUM
NO LE
SI E**
SHIPPED
NO LE
SI E
OIL PUMP
PRESSURE
(PSIG)
OL6*A072D**C 99032B
N
E -1HP
4.5”
N/A
N/A
0.75X60° A
0.60X60°A 120
OL8*A119T**C 99032C
N
E -1HP
4.5”
N/A
N/A
0.90X60° A 0.85X60° A 140
Riello oil burner application
FURNACE
MODEL
THERMO
PRIDE’S
BURNER
SPEC NO.
INS
+
RIELLO
BURNER
MODEL &
TUBE
LENGTH
HEAD
STATIC
PLATE
MAXIMUM
NO LE
SI E**
SHIPPED
NO LE
SI E
OIL PUMP
PRESSURE
(PSIG)
OL6*A072D**R C8511325 S BF3-4.5”
N/A
N/A
0.70X80° A
0.60X80° A
140
OL8*A119T**R C8512317 S BF5-4.5”
N/A
N/A
1.00X80° A 0.85X80° A 140
Table 4: Beckett, Carlin & Riello burners specifications
+ INSULATOR S = SLEEVE OR N = NONE
THE NOZZLE SIZE GIVES THE NOMINAL FLOWRATE, IN GPH, FOLLOWED BY
THE SPRAY ANGLE, IN DEGREE’S, AND THE SPRAY PATTERN, EITHER “A” FOR
HOLLOW CONE OR “B” FOR SOLID CONE. FOR EXAMPLE, A NOZZLE RATED
AT 0.65 GPH @ 00 PSIG THAT PROVIDES AN 80° SPRAY ANGLE AND A HOLLOW
SPRAY PATTERN WOULD BE ABBREVIATED IN THE TABLE AS “0.65 X 80°A”.

All installations and services must be performed by qualified service personnel.
10
For more specific burner information, contact:
Thermo Products, LLC
PO Box 237
Denton, NC 27239
800-348-5 30
OIL NOZZLE CAPACITY CHART
UNITS
NOZZLE SIZE (GPH) EQUIVALENT
HEAT INPUT
RATE* (BTU/HR)
EFFECTIVE
HEATING
CAPACITY**
(BTU/HR)
Beckett Carlin Riello
OL6*A060D***
.50
.50
.50
70,000
60,000
OL6*A072D***
.60
.60
.60
85,000
73,000
OL6*A090D***
.75
.75
.70
106,250
90,000
OL8*A101T***
.85
.75
.75
119,000
101,000
OL8*A119T***
1.00
.85
.85
140,000
119,000
OL8*A132T***
1.10
.90
1.00
156,250
132,000
Table 5
All rates shown achieved with 120 PSIG pump pressure for Beckett AFG.
* Based on #2 domestic heating fuel oil having heating value of 140,000 BTU per gallon.
** Based on thermal efficiency of 84%-85%.

11
All installations and services must be performed by qualified service personnel.
H. HEAT EXCHANGER CLEANING INSTRUCTIONS:
cWARNING: 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. Remove clean-out plugs, the vent
connector pipe to the chimney, the burner, and the burner mounting plates. When removing the
clean-out plugs, remove the screw at the 12 o’clock position. Then, pull clean-out plug straight
back.
Fig. 5: Heat Exchanger Clean-Outs
Outer Radiator
Vacuum Hose Length OL6 8FT
Vacuum Hose Length OL8 8FT
Fig. 6: Recommended method and device for cleaning inside of heat exchanger.

12
All installations and services must be performed by qualified service personnel.
All installations and services must be performed by qualified service personnel.
I. FAN CONTROL BOARDS:
Thermo Pride oil furnaces can be equipped with one of the following two boards. Please refer to
Fig. 7 to see which board you have.
Wiring Diagrams and Fan Speed Charts can be found in this manual under Appendix B and
Appendix C.
UT Fan Control Board NRGmax Fan Control Board
Fig. 7: Fan Control Board
Note: Refer to ECM Operation Manual for ECM board information.

13
All installations and services must be performed by qualified service personnel.
Operating Modes for UT board (PSC)
Standby Mode
All outputs are off and the control is waiting for a thermostat demand. The thermostat inputs, and
limit switch are continuously monitored. The control initiates action when a thermostat call is
received or limit switch opens.
Fan Mode
A call for fan (“G”) is received from the thermostat. If no other mode is calling for blower
operation, the control will operate the fan relay (K4) and power the “Low” blower speed
terminal. The fan mode will be operated as long as the “G” input is calling and neither the Heat
mode nor the Cool mode is calling for blower operation. When the Heat and Cool modes call for
blower operation, their respective outputs will take precedence after their respective turn-on time
delays have expired.
Cooling Mode
A call for cool (“Y”) is received from the thermostat. If the heat mode is not active or the anti-
short cycle delay is not in effect, the control will energize the “CC” terminal and after a 10
second power demand conservation delay energizes the “COOL” speed blower terminal.
When the call for cool is satisfied, the “CC” terminal is de-energized and the cooling off delay of
45 seconds is started. Forty-five seconds later the “COOL” speed blower terminal is de-
energized and the control reverts to Standby Mode.
Dehumidification Operation
If a call for dehumidification is received while the Cool Mode is active, blower speeds will be
reduced. The “COOL” blower speed terminal will be de-energized and “Low” blower speed will
be energized.
Anti-Short Cycle Operation
To prevent compressor short cycling, a call for cooling will be ignored for four minutes after the
termination of any cooling call. The anti-short cycle delay is also in effect at power-up.
EAC (electronic air cleaner)
If a call for fan (“G”), cool (“Y”) or heat (“W”) is received from the thermostat, the “EAC”
terminal is energized whenever the blower is energized to power an electronic air cleaner.

14
All installations and services must be performed by qualified service personnel.
Heat Mode
When a call for heat (“W”) is received from the thermostat, if the “Cool” mode is not already
active, the “T-T” terminal is energized and the blower on delay is started. The on-off pattern of
DIP switch SW2 (positions 1 and 2) select one of four blower on delay values (see Table 6).
When the delay time has elapsed, the “HEAT” blower speed is energized. The control remains
in steady heat mode until the thermostat is satisfied. When the call for heat signal is removed, the
“T-T” terminal is de-energized and the blower off delay is started. The on-off pattern of DIP
switch SW2 (positions 3 and 4) select one of four blower off delay values (see Table 8). When
the delay time has elapsed, the “HEAT” blower speed terminal is de-energized.
DIP SWITCH 2 SECTION
STATE BLOWER DELAY TIMES
1 2 3 4
Counter
Flow
ON - SEC
ON -
SEC
OFF -
MIN
OF
F OFF 15 30
ON OFF 24 60
OF
F ON 36 120
ON ON 48 240
OFF OFF 2
ON OFF 4
OFF ON 6
ON ON 8
Table 7: ON and OFF Blower Delay Time Switch Settings

15
All installations and services must be performed by qualified service personnel.
Motor Blower Speed
Three interconnected blower speed outputs are provided. A “G” call for fan will provide
power to the LOW speed tap only. A “W” heat call will provide power to the Heat speed tap
only. A “Y” cooling call will provide power to the Cool speed tap only.
In the case of thermostat calls for “Y” and “W” together, blower speed selection will be
determined by the input that was first initiated. In the case where the control is in a cooling mode
with both “Y” and “W” inputs energized and then the “Y” input is removed, the cooling blower
off time will be executed prior to the control switching into a heating mode. In the case where
the control is in a heating mode with both “Y” and “W” inputs energized and then the “W” input
is removed, the heating blower off time will be executed prior to the control switching into a
cooling mode. In the case where a call for fan “G” already exists and either a “W” or a “Y” call
is initiated, the blower speed will switch to the respective “W” or a “Y” speed following the
blower on delay for that call.
The speed taps are interconnected and interlocked, only one speed may be powered at any one
time. When a speed is to be operated, the speed select relays are operated to select the path to the
motor tap and then the enable relay is operated to switch the operating power to the selected
motor speed tap. If the speed of the running motor is to be changed, first the enable relay
removes power from the motor, the new speed is selected and then power is restored to the
motor.
Blower On and Off Delays
Four Heat blower on and four blower off delays are selected by two dip switches for each
function. Refer to Table 8 for specific delay values.
Trouble Shooting - Diagnostic Features for UT board
The control board is equipped with 4 green Input Status LEDs and 1 red Board Status LED.
These are intended to provide a quick view into furnace performance without requiring a
voltmeter.
The green Input Status LEDs are driven by the “Y”, “W”, “G”, and “DEHUM” inputs and are
located directly below those inputs. They will light to indicate the presence of these signals.

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All installations and services must be performed by qualified service personnel.
The red Board Status LED has two functions:
It will light when the board recognizes a valid input signal and will stay lit until all valid signals
are removed. This is intended to show that the board is functioning and able to respond to input
signals.
It will flash rapidly while 120VAC is missing from the LIMIT switch. This is intended to give a
quick visual indication of the High Limit switch.
Operating Modes for NRGmax board
Standby Mode
All outputs are off and the control is waiting for a thermostat demand. The thermostat inputs, and
limit switch are continuously monitored. The control initiates action when a thermostat call is
received or limit switch opens.
Fan Mode
A call for fan (“G”) is received from the thermostat. If no other mode is calling for blower
operation, the control will operate the fan relay and power the “Low” blower speed terminal. The
fan mode will be operated as long as the “G” input is calling and neither the Heat mode nor the
Cool mode is calling for blower operation. When the Heat and Cool modes call for blower
operation, their respective outputs will take precedence after their respective turn-on time delays
have expired.
Cooling Mode
A call for cool (“Y”) is received from the thermostat. If the heat mode is not active the “COOL”
speed blower terminal is energized. When the call for cool is satisfied, the “COOL” speed
blower terminal is de-energized, the “HEAT” speed blower is energized and the blower off delay
of 45 seconds is started. Forty-five seconds later the “HEAT” speed blower terminal is de-
energized and the control reverts to Standby Mode.
Dehumidification Operation
If a call for dehumidification is received while the Cool Mode is active, blower speeds will be
reduced. The “COOL” blower speed terminal will be de-energized and “Heat” blower speed will
be energized.
EAC (electronic air cleaner)
If a call for fan (“G”), cool (“Y”) or heat (“W”) is received from the thermostat, the “EAC”
terminal is energized whenever the blower is energized to power an electronic fan cleaner.