Midco Unipower VA Series Quick guide

Installation and Service Instructions
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• In the United States, installation must conform with local
codes or in the absence of local codes, with the National
Fuel Gas Code, ANSI Z223.1-latest edition available from
American National Standard Institute. Further reference
should be made to the recommendation of your fuel supplier.
• In Canada, installation must conform with local codes or in
the absence of local codes, with Installation Codes for Gas
Burning Appliances and Equipment, Standard CAN/CGA
1-B-149.1 or 2.
• WARNING: Additions, changes, conversions and
service must be performed by an authorized Midco
representative, service agency or the fuel supplier. Use
only MIDCO specified and approved parts.
• INSTALLER: Inform and demonstrate to the user the correct
operation and maintenance of the gas utilization equipment.
Inform the user of the hazards of storing flammable liquids
and vapors in the vicinity of this gas utilization equipment
and remove such hazards. Affix this manual and associated
literature to the burner.
• CODE COMPLIANCE IS THE SOLE RESPONSIBILITY OF
THE INSTALLER.
• USER: Retain this manual for future reference. If other than
routine service or maintenance as described in this manual
and associated literature is required, contact a qualified
service agency. DO NOT ATTEMPT REPAIRS.
An inadvertent service error could result in a dangerous
condition.
Midco® International Inc.
4140 West Victoria Street
Chicago, Illinois 60646
toll free 866.705.0514
tel [phone]
fax [phone]
web www.midcointernational.com
e-mail [email protected]
AVOID ERROR IN PARTS SELECTION. When ordering use
complete MIDCO Part Number and Description. Furnish Burner
Model Number, Bill of Material Number and Serial Number (if avail-
able) from the specification plate found on the product
IMPORTANT: Availability of parts as well as specifications are
subject to change without notice. Please consult factory for item
availability.
Quality Designed for Proven Performance
WARNING: If the information in these instructions
is not followed exactly, a fire or explosion may result,
causing property damage, personal injury or death.
Do not store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.
WHAT TO DO IF YOU SMELL GAS:
• Do not try to light any appliance.
• Do not touch any electrical switch; do not use any phone in
your building.
• Immediately phone your gas supplier from another building.
Follow the gas supplier’s instructions. If you cannot reach
your gas supplier call the fire department.
Installation and service must be performed by a qualified
installer, service agency or the gas supplier.
!
SAFETY INFORMATION TERMS: The following terms are used to identify hazards, safety precaution of special
notations and have standard meanings throughout this manual. They are printed in all capital letters using a
bold type face as shown below, and preceded by the exclamation mark symbol. When you see the safety alert
symbol and one of the safety information terms as shown below, be aware of the hazard potential.
DANGER: Identifies the most serious hazards which will result in severe personal injury or death.
WARNING: Signifies a hazard that could result in personal injury or death.
CAUTION: Identifies unsafe practices which would result in minor personal injury or product and
property damage.
BURNER MODEL: _____________________________________
BILL OF MATERIAL
NUMBER: ____________________________________________
SERIAL NUMBER #: ___________________________________
WIRING DIAGRAM: ____________________________________
FOR SERVICE CONTACT
Name: ____________________________________________
Address: ____________________________________________
____________________________________________
Phone: ____________________________________________
Date of Installation: ___________________________________
Printed in USA
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8471 95
420C
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Unipower VA Series
120 Volt Variable Air Gas Burners - Models V1 to V10
24 Volt Variable Air Gas Burners - Models V1 and V2

2Midco International Inc. 8471 95
Part 1 Installation
Specifications 1
For 120 Volt Burners:
The VA Series - 120V, Models V1 to V6 burners with intermittent spark ignited pilots and V7 to V10 with interrupted pilots, are
adaptable to most gas utilization equipment, including furnaces, heat exchangers and process ovens. They are particularly
recommended for firing high efficiency and high turndown applications.
For 24 Volt Burners:
The VA Series - 24 Volt , Models V 1 and V 2 burners with intermittent spark ignited pilots are adaptable to most gas utilization
equipment, furnaces, heat exchangers and process ovens. They are particularly recommended for firing high efficiency and high
turndown applications.
120 V 120 V 120 V 120 V 120 V 120 V 120 V 120 V 120 V 120 V 24 V 24 V
Burner Model V1 V2 V3 V4 V5 V6 V7 V8 V9 V10 V1 V2
Maximum Input
at 10″(MBH) 2,3 670 1,260 2,000 2,000 2,500 2,500 3,000 3,000 3,800 3,800 670 1260
Maximum Input
at 7″(MBH) 2,3 550 1,150 1,890 1,890 2,500 2,500 3,000 3,000 3,300 3,330 550 1150
Minimum
Input (MBH) 2,3 36 48 80 80 100 100 120 120 150 150 36 48
Turndown 19-1 26-1 25-1 25-1 25-1 25-1 25-1 25-1 25-1 25-1 19-1 26-1
Inlet Gas 4 (NG)
pressure for
maximum
firing rate W.C. 10.0″10.0″10.0″10.0″10.0″10.0″10.0″10.0″10.0″10.0″10.0″10.0″
Manifold gas (NG)
pressure for
maximum
firing rate W.C. 5.0″3.4″3.9″3.9″4.3″4.3″4.4″4.4″4.9″4.9″5.0″3.4″
Approximate
Air Delivery at
Zerog Draft (CFM) 115 210 360 360 440 440 620 620 720 720 115 210
Values given based on +0.5″W.C. combustion chamber pressure. (Maximum Firing Rate)
Minimum Recommended Chamber Size (Based on +0.5″Drafts) (Maximum Firing Rate) (Dimensions shown in inches)
Width in inches 18″24″34″28″42″30″48″36″54″36″18″18″
Height in inches 18″24″26″28″26″36″28″42″28″42″24″24″
Depth in inches 42″48″54″54″60″60″66″66″72″72″42″48″
Control Amps 1.3 1.6 1.5 1.5 2 2 2.1 2.1 2.1 2.1 1.3 1.6
Motor Amps 3.5 4.0 10.5 10.5 10.5 10.5 13 13 13 13 3.5 5.2
Total Amps 4.8 6.8 12 12 12.5 12.5 15.1 15.1 15.1 15.1 4.8 6.8
Motor HP .32 .50 1.10 1.10 1.10 1.10 1.75 1.75 1.75 1.75 35 40
1Standard burners are shipped as NATURAL gas models. Contact Midco for PROPANE gas burners.
21 MBH = 1,000 Btu/hr
3All Ratings Based on 1000 BTU/Cu. Ft. NATURAL, 2500 BTU/Cu. Ft. PROPANE at sea level. Derate burner for altitude over 2,000 feet by 4%
for each 1,000 feet above sea level.
4Lower gas inlet pressure may be used when maximum input is not required. Burner input based on +0.5″W.C. back pressure.
Table 1. Burner Specifications

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Midco International Inc.
8471 95
Part 1 Installation
CAUTION: The Unipower VA Series burners are not intended for outdoor installation
and must be protected from excessive moisture. Provide adequate clearance for
service and proper operation.
When installed indoors, the area must be checked for proper ventilation before installing.
Proper ventilation entails the following:
- Open areas of normal construction, without storm windows or tight doors, will generally allow
sufficient air infiltration. However, if the heating appliance is located in a tight or separate room,
ventilation to an open area as described below will be required. Install two permanently open grills,
each sized on the basis of one square inch free area per 10,000 BTU/hr (but not less than 50
square inches) of the total input rating of all gas utilization equipment in the combined space. One
grill should be located within 12ʺof the ceiling and the other within 12ʺof the floor.
- If the heating appliance is located in an area of unusually tight construction, or if an exhaust
fan, kitchen ventilation system, clothes dryer and/or fireplace is installed in the building, provisions
must be made for an outside air supply near the heating appliance area.
- In Canada, for detailed ventilation requirements, refer to standard CAN / CGA 1-B-149.1 or 2
and/or local codes.
__________________________________________
Prepare the equipment front plate to have a rectangular hole for the insertion of the burner. To
fasten the burner to the equipment, either create four tapped holes on the front plate and use bolts
to fasten the burner, or install four threaded studs and fasten the burner with a washer and nut. The
dimensions and locations of the holes or studs are shown in Figure 1.
- Clean the gas utilization equipment combustion chamber, heat exchanger interior, and flue
connections. Remove all adhering tars, scale, dirt and soot. Inspect for actual or potential leaks.
B Height Insertion*
120V A-Width in Inches C -Depth D-Depth
Model Desc. in Inches Honeywell Siemens in Inches in Inches
V1 6″Straight 17″28.5″31.8″19.25″6″
V2 12″Straight 17″30.75″34″19.5″6″
V3 18″Straight 20.75″33″36.3″23″6″
V4 18″Tee 20.25″34.75″38″23.25″6″
V5 24″Straight 24.5″33″36.3″23″6″
V6 24″Tee 20″40.75″44″23″6″
V7 30″Straight 32.75″37″40.3″22.5″6″
V8 30″Tee 32″33.5″37″25″6″
V9 36″Straight 39″37″40.3″22.5″6″
V10 36″Tee 32″31.5″34.8″22.5″6″
24 V
V1 6″Straight 16.97″28.42″19.11″6″
V2 12″Straight 16.97″30.6″19.5″6″
Dimensions are approximate - contact factory for additional information
*Longer insertion depth available - contact factory
___________________________________________
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Part 1
Installation
I Ventilation
II Preparation for
Combustion
Chamber and
Gas Utilization
Equipment
VA Series - 12” Mounting HoleVA Series - 6” Mounting Hole
13.31”
7.25”
7.25”
8.75”
4.16”
4.16”
5.00”
9.00”
13.25”
13.25”
8.75” 13.31”
4.16”
4.16”
5.00”
15.00”
Figure 1 - Mounting Hole/Stud Locations for standard VA Series (6″Mounting Hole)
and the VA Series (12″Mounting Hole) burners
NOTE: Contact factory for actual hole/stud locations for other VA series models
Front View Side View
A
B
C
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Figure 2 - VA Dimensions Standard 120V V1 to V10
and 24V V1 & V2

4Midco International Inc. 8471 95
Part 1 Installation
CAUTION: The VA Burner must be protected from excessive moisture. Provide
adequate enclosure to protect from the weather.
- The burner mounting flange should be sealed to the combustion chamber by means of a ceramic
based high temperature gasket (supplied with the burner).
- Make sure the gasket fits over the burner housing, flush against the mounting flange.
- Insert the burner into the rectangular hole until the mounting flange is tight to the exchanger front
plate.
- Tighten flange. During the tightening process, the gasket will be compressed creating the seal that
is needed.
CAUTION: Flue gas leakage will cause equipment damage and may affect the
operation of the equipment.
NOTE: During the initial startup of the burner, a small portion the new gasket may be oxidized and
some white smoke and burning odor will present. This is normal.
CAUTION: If the smoke persists and visible leakage of the flue gas is observed,
recheck the seal. This may require removing the burner from the heat equipment.
__________________________________________
The standard V Series burner valve train is pre-assembled and pre-wired, but it will need to be
installed to the burner. There are three parts that need to be connected: the main gas valve train, the
pilot gas supply line and the air pressure line. See Figure 3.
Following are the instructions for
assembling the valve train:
1. Connect the union on the main gas
valve train to the union on the burner
(Figure 3 - #1).
2. Connect the gas supply line to the
shut-offvalve next to the main regulator
(Figure 3 - #2).
3. Connect air pressure line from the
compression fitting on the burner housing
to the brass compression fitting on the
ratio regulator (Figure 3 - #3).
4. Connect the Pilot Gas Supply Line
to the brass compression fitting that is on
pilot gas solenoid valve, which is mounted
on the burner control box, and the other
end to the tubing has to be connected to
the brass fitting at the 1/8″Tee next to the
pilot regulator (Figure 3 - #4). (Note: On
some variations, the pilot gas solenoid
valve is not mounted on the control box.
In this case, refer to the assembly drawing
provided with the VA burner.)
5. Low fire bypass (Figure 3 - #5).
6. Supply gas pressure tap (Figure 3 - #6).
CAUTION: The available gas pressure should be within the limits shown in the
SPECIFICATIONS section, Table 1. Excessive pressure may damage safety shut-off
valves, regulators or manual valves.
Approximate Capacity -MBH
Pipe Type Pipe Length
Size of Gas 10 ′20 ′40 ′75 ′100 ′
1 ″Propane 1075 730 500 360 300
1 ¼ ″Natural 900 600 450 325 275
1 ¼ ″Propane - - 1040 750 630
1 ½ ″Natural 900 650 475 400 -
1 ½ ″Propane - - - - 975
III Burner
Mounting
Instructions
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IV Piping
1
4
3
2
Pilot Gas
Supply Line
Air
Pressure
Line
Main Gas
Valve
Train
56
Figure 3 - Typical Valve Train Assembly, UL
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Table 2: Schedule 40 NPT Pipe - Capacity Chart
Capacities shown are for a total pressure
drop of 0.3″W.C.. For 0.5″W.C. pressure
drop, multiply capacity shown by 1.3.
Propane capacities shown are for a total
pressure drop of 0.5″W.C.. For higher
permissible pressure drops, consult your
gas supplier.
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Midco International Inc.
8471 95
Part 1 Installation
- The burner gas supply piping should branch offfrom the main line as close to the gas meter as
possible. Do not connect to the bottom of a horizontal section. Use new black pipe and malleable
fittings free of cutting and threading burrs or defects.
- Use pipe joint compound approved for use with natural and propane gases.
- Piping must also comply with your local codes.
- When high supply gas pressure is encountered, as is the case in many industrial plants,
the gas line size can be reduced to allow for a greater pressure drop; however, the size must be
sufficient to deliver burner rating pressure.
CAUTION: High gas pressure supply lines require the proper pressure reducing
regulators. Install a high pressure regulator of the Tight Shut-Offtype upstream
of the low pressure regulator sized for main gas input. .
CAUTION: Because it is difficult to accurately control pressure during supply pipe
leak testing, it is recommended that all low pressure components, both main and
pilot, be only exposed to 14.0″W.C. maximum. Exposing low pressure regulators
and valves, including manual valves, to pressures over 1/2 PSIG (14.0″W.C.) will
cause damage and void all warranties.
- To obtain the maximum firing rate of the burner, the gas supply piping must be sized to provide
a minimum of 10.0″W.C. pressure to the inlet of the upstream automatic safety shut-offvalve when
the burner and all other gas utilization equipment are on.
- If the burner piping must be rearranged because of space limitations, be sure to carry out the
general arrangement shown in Figure 9 on page 29. Refer to valve and regulator manufacturer
specifications for acceptable mounting orientations.
- When the burner is installed in the vestibule of jacketed equipment, it is recommended that the
Automatic Safety Shut-OffValves be left adjacent to the burner within the vestibule and the Main
Manual Shut-OffValve be installed outside.
- Run full size pipe or tubing from regulator vent openings to outside of building. Provide no traps
in the vent lines and terminate away from all doors and windows; also make provisions for keeping
rain and foreign objects from entering the vent piping.
- When the gas supply line is about to be put into service it must be tested to ensure that it is gas
tight. Use air or inert gas under pressure and test with soap and water to locate leaks.
DANGER: Explosion hazard.
Do not use oxygen for pressure testing.
An explosion could occur during initial start up.
- Before gas is turned on to the system, a check must be made to see that there are no open
fittings and to make sure the burner main and pilot manual valves are closed.
- After checking for leaks, purge the gas line up to the burner inlet. Purging the air from the gas
supply line at this step will expedite the first light-off.
WARNING: Explosion Hazard. Improper installation can cause fuel buildup and an
explosion.
__________________________________________
CAUTION: Refer to wiring diagram located on the inside of the burner housing cover.
Before proceeding verify burner model number for correct wiring diagram. Refer to
Figures 4A / 4B / 4C / 4D for 120V models and 4E for 24V models.
- Installation wiring and grounding to the burner must conform to local codes, or in their absence
in the United States to National Electric Code ANSI/NFPA No. 70 latest edition and in Canada to
Canadian Electrical Code Part 1 CSA Standard C22.1.
- Use copper wire not less than 16 gage for line voltage wiring. Hook up to a dedicated line with
an on-offdisconnect switch and correctly size circuit breaker for the 120V models and a 10 Amp
breaker for 24V models. Refer to Table 1 for correct amp draw requirement.
- The frame of the burner should be well grounded. Normally the piping and/or electric conduit
will provide sufficient grounding. However, a ground lug is located in control box for positive
grounding where insulated pipe couplings are used or where any doubt exists regarding grounding
sufficiency.
IV Piping
Continued
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V Electrical
A - Safety

6Midco International Inc. 8471 95
Part 1 Installation
- Confirm that the polarity is correct:
120V Burner Models:
for Honeywell control - hot wire to strip terminal 10, neutral 6—and that the neutral
line is not subject to induced low voltage (check 6 to 11 earth ground)
(refer to Figures 4A and 4B) ...
for Siemens control - hot wire to strip terminal 3, neutral 6—and that the neutral line is
not subject to induced low voltage (check 6 to 1 earth ground)
(refer to Figures 4C and 4D) ...
24V Burners Models:
Confirm that the polarity is correct—hot wire to strip terminal L1, neutral L2—and that the
neutral line is not subject to induced low voltage (check L2 to earth ground) from other
equipment, as that can cause the Ignition Control Module to malfunction.
(refer to Figures 4E) ...
... from other equipment, as that can cause the Ignition Control Module to malfunction.
- Each installation must include suitable safety and limit controls.
- The current draw of the VA Series varies by model and is listed in the specifications section,
Table 1.
__________________________________________
CAUTION: Label all wires prior to disconnection when servicing controls. Wiring
errors can cause improper and dangerous operation. Verify proper operation after
servicing.
WARNING: Electrical Shock Hazard. Can cause severe injury, death or equipment
damage.
Most of the components have been pre-wired. There are a few things that the installer has to wire
to integrate the burner into the system. Refer to Figure15 for the component’s location inside the
control box.
1. Main 120V power supply to the burner: Locate the terminal strip inside the control box.
There are three wires that need to be connected:
120V Burner Models:
for Honeywell control - 10 (Black), 6 (White), and 11 (Green) (refer to Figures 4A and 4B).
for Siemens control - 120V (On Offswitch), 8 (Neutral), and 1 (Ground) (refer to Figures
4C and 4D).
24V Burner Models:
L1 (Black), L2 (White), and G (Green). (refer to Figures 4E)
Note: For 240 V versions, refer to the wiring diagram specific to your burner for main power wiring
instructions. Refer to the specification label located on the control box door to determine whether
your burner requires 120 or 240 VAC power.
2. Modulation signal input (2-10VDC): Connect the signal input wires from the temperature
controller to the appropriate terminals on the terminal strip. There are two wires that need to be
connected:
120V Burner Models:
for Honeywell control - positive 13 (+) and 14 negative (-) (refer to Figures 4A and 4B).
for Siemens control - positive 10 (+) and 9 negative (-) (refer to Figures 4C and 4D).
24V Burner Models:
positive (+) and negative (-) (refer to Figures 4E)
3. Main gas solenoid valve wiring: Connect the main gas valve wires from the gas valves to the
appropriate terminals on the terminal strip. There are three wires that need to be connected:
120V Burner Models:
for Honeywell control - 2 (Blue), 7 (Blue/White) and 12 (Green) (refer to Figures 4A
and 4B).
for Siemens control - 8 (Blue), 5 (Blue/White) and 1 (Green) (refer to Figures 4C and 4D).
24V Burner Models:
L (Blue) N (Blue/White) and G (Green). (refer to Figures 4E)
4. Call for Heat: The call for heat circuit should be wired between:
for Honeywell control - terminals 8 and 15 (refer to Figures 4A and 4B).
for Siemens control - terminal 3 to Siemens X5-03 1 (refer to Figures 4C and 4D).
The switch should be capable of handling the full current load of the burner.
5. (Optional) Gas pressure switch and proof of closure wiring: If applicable, connect the
wires from the gas pressure switches and/or proof of closure switch to the corresponding terminals
inside the control box. Refer to the wiring diagram inside the control box door for additional
information.
A - Safety
Continued
V Electrical
Continued
B - Wiring
Instructions
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7
Midco International Inc.
8471 95
Part 1 Installation
120V Intermittent Pilot Version with Honeywell Flame Safeguard
V Electrical
Continued
10
BK
BK
ON/OFF SWITCH
NEUTRAL
120/1/60
HOT
6
R
R
HIGH A/S
RLOW A/S
R/W
R/W
R/BK
14 13
95
4
120V
RELAY
11
W
12
TEMPERATURE CONTROL
11
GROUND
W
BK
+
-
5
6
7
1
R
SCEBM-2
INPUT1
21
MAIN GAS VALVES
BL BL/W
9
2
SCEBM-2
INPUT2
4
3
PILOT GAS VALVE
BK BK
8
3
L2
5
7
5
7
7
12
IGNITION TRANSFORMER
3
OPTIONAL 120V ALARM
4
BLOWER
10
F
G
BL BL/W
BL
BR BR/W
BR
W
BR
BK
G
O/W
BL
W
14
15
BLOWER
16
Y
R
BL
BL/W
BL
G
G
13
SCEBM-2 FAN
W
15
6
B
Y
A
14
13
SCEBM-2 2-10V
COM
BL Y
24V
RED
ORN
120V
SCEBM-2
24VAC 87
BK
6
8
4
9
BK
BL Y
1
1
1
3
3
2
2
BL
O
O
W
W
CALL FOR
HEAT
14 13
95
4567
89
10
11 12
TERMINAL STRIP
JUMPERS
LEGEND
F
5
SOLID WIRING AND
DASHED WIRING AND
ENCIRCLED: FLAME
SOLID ROUND:
OPEN ROUND: COMPONENT
BK
12
14 13
9
++
++
5
++
8
41
++
RELAY
SOCKET
COMPONENTS BY MIDCO
COMPONENTS BY INSTALLER
SAFEGUARD
TERMINAL BLOCK STRIP
B - Wiring
Instructions
Continued
Figure 4A: Wiring Diagram for the VA series models
120V Intermittent Pilot Version with Honeywell Flame Safeguard

8Midco International Inc. 8471 95
Part 1 Installation
V Electrical
Continued
B - Wiring
Instructions
Continued
120V Interrupted Pilot Version with Honeywell Flame Safeguard
R
R
HIGH A/S
RLOW A/S
R/W
R/W
R/BK
14 13
95
4
120V
RELAY
12
TEMPERATURE CONTROL
11
W
BK
+
-
6
7
1
R
SCEBM-2
INPUT1
21
MAIN GAS VALVES
BL BL/W
9
2
SCEBM-2
INPUT2
4
3
PILOT GAS VALVE
BK BK
8
3
7
5
7
7
IGNITION TRANSFORMER
4
10
F
BL BL/W
BL
BR BR/W
BR
W
BR
O/W
BL
BL/W
BL
G
G
B
Y
A
14
13
SCEBM-2 2-10V
6
8
1
1
1
3
3
2
2
BL
O
O
W
W
14 13
95
4567
89
10
11 12
TERMINAL STRIP
JUMPERS
LEGEND
F
5
SOLID WIRING AND
DASHED WIRING AND
ENCIRCLED: FLAME
SOLID ROUND:
OPEN ROUND: COMPONENT
12
14 13
9
++
++
5
++
8
41
++
RELAY
SOCKET
COMPONENTS BY MIDCO
COMPONENTS BY INSTALLER
SAFEGUARD
TERMINAL BLOCK STRIP
UV SCANNER
BL
6
6
W
GAS PRESSURE SWITCHES
BK
15
Y/BK
CALL FOR
HEAT
10
BK
NEUTRAL
120/1/60
HOT
6
11
W
GROUND
5
L2
5
12
3
OPTIONAL 120V ALARM
BLOWER
G
BK
G
W
14
15
BLOWER
16
Y
R
BL
13
SCEBM-2 FAN
W
6
COM
BL Y
24V
RED
ORN
120V
SCEBM-2
24VAC 87
BK
4
9
BL Y
BK
Y/BK CNO
NC
LO HI
CNO
NC
W
Y/BK
ON/OFF
Figure 4B: Wiring Diagram for the VA series models
120V UV Interrupted Pilot Version with Honeywell Flame Safeguard

9
Midco International Inc.
8471 95
Part 1 Installation
V Electrical
Continued
B - Wiring
Instructions
Continued
120V Intermittent Pilot Version with Siemens Flame Safeguard
NEUTRAL
120/1/60
HOT
RR/W
14 13
95
12
TEMPERATURE
CONTROL
11
LEGEND
5
SOLID WIRING AND
COMPONENTS BY MIDCO
DASHED WIRING AND
COMPONENTS BY INSTALLER
SOLID ROUND: TERMINAL
BLOCK STRIP
OPEN ROUND: COMPONENT
+
-
R
SCEBM-2
INPUT1 2
1
BL
SCEBM-2
INPUT2 4
3
PILOT GAS VALVE
BLOWER
BL
BR
W
O/W
14
15
BLOWER
16
13
SCEBM-2
FAN
11
12
SCEBM-2
2-10V
BL Y
24V
R
SCEBM-2
24VAC 8
7
23
BL Y
14
14
9
9
10
10
O
O
W
678
23
TERMINAL STRIP
JUMPERS
65
BK
BK
G
Y
R
BL
W
8
1
12
14 13
9
+
+
+ +
5
+ +
8
41
+
+
RELAY
SOCKET
B
4
3
6
5
72
81
RELAY
SOCKET
A
++
++
++
++
A
B
R/BK
R
120V
W
BK
Y
W
13
SIEMENS
LME71.000A1
1
X9-04
3
X5-01
2123
X3-02
2
1
X5-03
12342
X2-01
3
14
32
1
X2-02 X6-03
132
X3-04
132 45
X2-03
23
1
X10-06
123
X10-05
2
145
X4-02
23
1
432
1
X7-04X7-01
132
PME71.111A1
DISPLAY
OFF - Standby, waiting for
call for heat
P24 - Fan motor on, Actuator
opens in high-fire
P30 - Prepurging
P36 - Actuator closes to
ignition position
P38 - Preignition, Sparking
P40 - Ignition, Gas valve on
P44 - End of safety time
oP - Operation, modulating
operation
.oP - Present output, %
FL. - Flame current, %
Loc - Lockout
P74 - Post purging
BK
X65
12
X66
123
X76
1234
X56
1234
IGNITION
TRANSFORMER
BL or W
BR or BK
10
BL
R
LOW A/S
R/BK
BK
O
4
BK
R/W
14
CALL FOR
HEAT
5
9
BR
1
W8
Y
13 R/W HIGH A/S
HIGH LIMIT
CNC
NO
Y
G
R
ON/OFF
SWITCH
ALARM
6
JUMPER
JUMPER
JUMPER NOTE: IF CIRCUIT IS USED;
REMOVE JUMPER
FLAME SENSE ROD
SPARK ROD
W
MAIN GAS VALVES
8
6
6
7
7
7
BL/W
BR/W
8
8
W
R
W
BL/W
1
GG
BL/W
BL
G
G
FUSE
45
45
BK
Figure 4C: Wiring Diagram for the VA series models
120V Intermittent Pilot Version with Siemens Flame Safeguard

10 Midco International Inc. 8471 95
Part 1 Installation
V Electrical
Continued
B - Wiring
Instructions
Continued 120V UV Interrupted Pilot Version with Siemens Flame Safeguard
NEUTRAL
120/1/60
HOT
RR/W
14 13
95
12
TEMPERATURE
CONTROL
11
LEGEND
5
SOLID WIRING AND
COMPONENTS BY MIDCO
DASHED WIRING AND
COMPONENTS BY INSTALLER
SOLID ROUND: TERMINAL
BLOCK STRIP
OPEN ROUND: COMPONENT
+
-
R
SCEBM-2
INPUT1 2
1
BL
SCEBM-2
INPUT2 4
3
PILOT GAS VALVE
BLOWER
BL
BR
W
O/W
14
15
BLOWER
16
13
SCEBM-2
FAN
11
12
SCEBM-2
2-10V
14
14
9
9
10
10
O
O
W
23
TERMINAL STRIP
JUMPERS
65
BK
G
Y
R
BL
W
8
1
12
14 13
9
+
+
+ +
5
+ +
8
41
+
+
RELAY
SOCKET
B
4
3
6
5
72
81
RELAY
SOCKET
A
++
++
++
++
A
B
R/BK
R
Y
W
13
SIEMENS
LME71.000A1
1
X9-04
3
X5-01
2123
X3-02
2
1
X5-03
12342
X2-01
3
14
32
1
X2-02 X6-03
132
X3-04
132 45
X2-03
23
1
X10-06
123
X10-05
2
145
X4-02
23
1
432
1
X7-04X7-01
132
PME71.111A1
DISPLAY
OFF - Standby, waiting for
call for heat
P24 - Fan motor on, Actuator
opens in high-fire
P30 - Prepurging
P36 - Actuator closes to
ignition position
P38 - Preignition, Sparking
P40 - Ignition, Gas valve on
P44 - End of safety time
oP - Operation, modulating
operation
.oP - Present output, %
FL. - Flame current, %
Loc - Lockout
P74 - Post purging
BK
X65
12
X66
123
X76
1234
X56
1234
IGNITION
TRANSFORMER
BL or W
BR or BK
10 BL
R
LOW A/S
R/BK
4
BK
R/W 14
CALL FOR
HEAT
5
9BR
1
W8
Y
13
R/W HIGH A/S
HIGH LIMIT
CNC
NO
Y
G
R
ALARM
6
JUMPER
JUMPER NOTE: IF CIRCUIT IS USED;
REMOVE JUMPER
SPARK ROD
MAIN GAS VALVES
8
6
6
7
7
7
BL/W
BR/W
8
8
W
R
W
BL/W
1
GG
BL/W
BL
G
G
UV SCANNER
R
W
GAS PRESSURE
SWITCHES
(3)C
(2)NO
(1)NC
(2)NO
(1)NC
(3)C Y
HI LO
Y
Y/BK
Y/BK
23
BK
BK
BK
ON/OFF
SWITCH
FUSE
45
BK
BL Y
24V
SCEBM-2
24VAC 8
7
BL Y
R
120V W
O
678
45
Figure 4D: Wiring Diagram for the VA series models
120V UV Interrupted Pilot Version with Siemens Flame Safeguard

11
Midco International Inc.
8471 95
Part 1 Installation
V Electrical
Continued
B - Wiring
Instructions
Continued
24V Intermittent Pilot Version
BK
BK
ON/OFF
SWITCH
BK
BK
BK
L2
L2
23
1
8
9
10
11
12
10
24
L2
W
120V
24V
BL G
Y
L2
R/W
R/W
4
4
HIGH A/S
4
4
R/BK LOW A/S
R
R
R
R
G
13
24
SCEBM-1
P8P7
MAIN GAS VALVES
BL/W
BR
PV
SCEBM-1
P12
P10
PILOT GAS VALVE
BR/W GND
BL
MV
OPTIONAL 120V ALARM
G
G
L2
G
120V
RELAY
24V RELAY
9 SECOND
24V RELAY
TIMER
BK
BK
BLOWER BK
SCEBM-1
P3P1 W
P9
SCEBM-1
P11
SCEBM-1 BLOWER
BLOWER
P13
SCEBM-1 BLOWER
Y
R
BL
Y
R
BL
12
P2
SCEBM-1 TEMPERATURE
CONTROL
P4
SCEBM-1 O/W
O
2
1
9
78
10
SPARK
SENSE W
BK
SE
SP
BR
BR
BR
BL
BL
BL
BL
BL/W
BL/W
BL/W
BR/W
BR/W
BR/W
BK
LEGEND
F
5
SOLID WIRING AND COMPONENTS
BY MIDCO
DASHED WIRING AND COMPONENTS
BY INSTALLER
ENCIRCLED: IGNITION CONTROL
SOLID ROUND: TERMINAL STRIP
OPEN ROUND: COMPONENT
-
+
W
11
13
L1
6
6
6
5
5
5
NEUTRAL
120/1/60
HOT
L2
BK
3
3
3
24V
24V
GND
G
GROUND
2-10V DC SIGNAL
SUPPLIED BY MIDCO INSTALLED
BY OTHERS
__________________________________________
Figure 4E:
Wiring Diagram for the V1 and V2 models - 24V Intermittent Pilot Version

12 Midco International Inc. 8471 95
Part 1 Installation
WARNING: Ignition is automatic. Confirm that gas utilization equipment does not
contain any accumulated gases. Purge as described in step 3 below.
CAUTION: Cover plates, guards, and enclosures must be maintained in place at all
times except during maintenance and service.
1. Check the burner piping and valves for gas leaks by applying a weak liquid soap solution to
unions and joints with the gas supply on. Leakage will be indicated by the appearance of soap
bubbles. Locate and correct all gas leaks before proceeding.
WARNING: DO NOT USE OPEN FLAME.
2. Purging the air from the gas supply line at this step will expedite first light-off.
IMPORTANT: Purge outside the building. Do not purge into the gas utilization equipment.
3. To purge the gas utilization equipment and chimney of any accumulated gases, turn main
Manual Gas Shut-offValve to OFF, close Pilot Manual Shut-OffValve, turn burner power ON, and
set operating control to ON to call for heat. Let the blower run long enough to accomplish four
combustion chamber volume air changes, but for not less than two minutes.
CAUTION: Make sure that the capacity range of the burner is suitable for capacity
rating of the gas utilization equipment. Refer to Specification Section page 2
4. RESET the 120 volt RM7895 flame safeguard by pushing its reset button. RESET the LME71
flame safeguard by holding down the info button for one second. See Section VIII.
5. Confirm that both the Main and Pilot Manual Shut-OffValves are open. Turn main Manual Gas
Shut-offValve to ON.
6. Turn operating control to ON. After the prepurge is complete, the pilot should ignite. Whenever
the burner pilot fails to light during the ignition trial, or if the flame is lost during the burner run
and is not reestablished within 15 seconds after the prepurge, the ignition system will shut off
the Automatic Safety Shut-offValves and LOCK OUT. For the 120V models RESET the flame
safeguard as described above. If burner still fails to light, turn it offand repeat from step 4 above.
For the 24V models RESET the 24 volt ignition Control Module by setting the operating control to
OFF for at least 30 seconds. Then if necessary, refer to Section XII to isolate the problem.
__________________________________________
1. With the burner off, install a barb fitting on the ⅛″ NPT pressure tap downstream of the pilot
regulator.
2. Use flexible tubing to hook up a manometer to the barb fitting.
3. Turn the burner to ON. After the 30 second pre-purge, the pilot solenoid valve should open.
With the pilot solenoid valve open, adjust the pressure with the pilot regulator based on the type of
pilot that is installed. For internal pilots, set the pressure to 3.0″W.C.. For external pilots, set the
pressure to 1.5″W.C..
__________________________________________
1. Open Manifold Gas Shut-offValve, see Figure 5.
2. Adjust the input signal to 2.0V DC.
3 Use the sight glass on the back plate of the burner to look at the low fire. If light is visible
through all of the holes in the burner plate, the low fire is set within the range of operation of
the burner. If light is not visible through all of the holes, then the low fire is too low and the low
fire bypass located on the side of the ratio regulator, see Figure 9 item # 6, needs to be opened
(counter-clockwise to open, clockwise to close).
__________________________________________
VI Initial
Start-up/Adjustment
for 120V and 24V
!
!
A - Initial Light
Up
!
!
i - Reset 120V
ii - Reset 24V
B - Pilot Pressure
Pilot Gas Manifold
Pressure Tap
Pilot Gas
Pressure
Regulator
Supply Gas
Pressure Tap
Main Manual
Gas Shut-off
Valve
Main Gas Pressure
Regulator
Figure 5 - Pilot Gas Pressure Tap and Regulator
C - Low Fire
Adjustment

13
Midco International Inc.
8471 95
Part 1 Installation
For 120V Burners:
1. Use a manometer to check the manifold pressure near where the valve train attaches to
the burner, see Figure 9 - item # 3 page 29.
2. Use another manometer to check the load pressure on the ratio regulator, see
Figure 9 - item # 5 page 29.
3. Modulate the burner until the load line pressure is 2.0″W.C. by adjusting the input voltage to
the burner.
4. Verify that the manifold pressure is within the values given in Chart 1.
5. If necessary turn the screw on the ratio regulator, see Figures 6A and 6B below, in order to
adjust the manifold pressure. 120V Burners
Model Pressure
V1-V4 0.8-0.9″W.C.
V5-V6 0.2-0.3″W.C.
V7-V10 0.5-0.6″W.C.
For 24V Burners:
1. Use a manometer to check the inlet pressure on the tee on the upstream side of the pilot
regulator, see Figure 10 - item # 12, page 30.
2. Use another manometer to check the main gas regulator outlet pressure on the
upstream side of the most upstream solenoid valve, see Figure 10, item # 9, page 30.
3. Turn the burner up to its actual firing rate applying an input signal of 10V DC for
maximum firing rate
4. Confirm that the inlet pressure remains between the maximum and minimum values
specified on the Burner Rating Label, see Figure 7 below.
5. The main gas regulator outlet pressure should be 1″W.C. higher than the minimum
pressure required figure on the Burner Rating Label see Figure 7 below.
a. When “Pressure Required” is 7.0″set the main gas regulator outlet pressure at 8.0″
b. When “Pressure Required” is 10.0″, set the main gas regulator outlet pressure at
11.0″
_____________________________________
i - Verify 120V
VI Initial
Start-up/Adjustment
for 120V and 24V
Continued
D Verify the Ratio
Regulator
Adjustment
Table 3A. - Pressure Load Settings
Figure 6A - Dungs FRG Ratio Regulator Adjustment - Figure 6B
Figure 6.
ii - Verify 24V
UNIPOWER VA Gas Burner
®
MODEL:
SERIAL NO.:
BILL OF MATERIAL:
MINIMUM FIRING RATE: BTU/HR
FIRING RATE: BTU/HR
PRESSURE REQUIRED: W.C.
MANIFOLD PRESSURE: W.C.
MAX. CAPACITY: BTU/HR
PRESSURE REQUIRED: W.C.
MANIFOLD PRESSURE W.C.
VOLTS AMPS HZ PH HP
CONTROLS
MOTOR
2121-07
CHICAGO, IL 60646
NAT
No. Pl-100, 058
US
C
LISTED
L
U
®
Î
®
7”
10”
MAXIMUM INLET PRESSURE: 14” W. C.
Figure 7 Burner Rating Label

14 Midco International Inc. 8471 95
6. Use a manometer to check the manifold pressure near where the valve train attaches to
the burner, see Figure 10 - item # 3 page 30.
7. Use another manometer to check the load pressure on the ratio regulator, see
Figure 10 - item # 5 page 30.
8. Modulate the burner until the load line pressure is 2.0″W.C. by adjusting the input
voltage to the burner.
9. Verify that the manifold pressure is within the values given in Chart 2 page 15.
10. If necessary turn the screw on the ratio regulator, see Figure 6A & 6B below, in order to
adjust the manifold pressure.
24V Burners
Model Pressure
V1- V2 0.8-0.9″W.C.
__________________________________________
1. With the burner off, install a barb fitting on the ⅛″ NPT pressure tap downstream of the ratio
regulator. See Figure 9 item #3 (page 20) for location.
2. Use flexible tubing to hook-up a manometer to the barb fitting.
3. Turn the burner on and adjust the temperature controller to its maximum setting. Measure the
manifold pressure and compare it to Chart 1 for 120V burners and Chart 2 & 3 for 24V burners.
For 120V Burner Models
4. Adjust the high fire by turning the span knob on the 120V burner SCEBM-2 board. Measure
the manifold pressure and refer to the Chart 1 for the 120V burner to match the manifold pressure
to the desired firing rate.
VI Initial
Start-up/Adjustment
for 120V and 24V
Continued
D Verify the Ratio
Regulator
Adjustment
Continued
Table 3B. - Pressure Load Settings
E - High Fire
Adjustment
i - Adjustment 120V
V1
V2
5
4
1.5
1
2.5
2
3.5
3
4.5
0.5
0
0 350030002500200015001000500
Manifold
Pressure
(Inches W.C.)
Firing Rate (mbtu/hr)
4000
V9 - V10V7 - V8
V5 - V6
V3 - V4
Chart 1 - Manifold Pressure vs. Firing Rate - VA 120V Burners
Part 1 Installation

15
Midco International Inc.
8471 95
For 24V Burner Models
Adjust the high fire by turning the span knob on the 24V burner SCEBM-1 board. Measure the
manifold pressure and refer to the Chart 2 and 3 for the 24V burner to match the manifold pressure
to the desired firing rate.
Note: Burners are not always set up to maximum capacity. Refer to the “Firing Rate” portion of
the Burner Rating Label or the Label of the heating equipment for the actual firing rate.
- Modulate the burner to high fire by applying a 10V DC input signal.
- Verify that the manifold pressure is the same as marked on the Burner Rating Label(s) for
the actual firing rate.
__________________________________________
VI Initial
Start-up/Adjustment
for 120V and 24V
Continued
V1
V2
5
4
1.5
1
2.5
2
3.5
3
4.5
0.5
0
0 15001000500
Manifold
Pressure
(Inches W.C.)
Firing Rate (mbtu/hr)
E - High Fire
Adjustment
Continued
ii - Adjustment 24V
Chart 2
Manifold Pressure vs. Firing Rate
24 V models V1 and V2 Burners
Chart 3
Load Line Pressure vs. Blower Speed
24V models V1 and V2 Burners
V1
V2
8
6
1
2
4
3
5
0
0 30025020015010050
Load Line
Pressure
(Inches W.C.)
Blower Speed (hz)
7
Part 1 Installation

16 Midco International Inc. 8471 95
If the burner is operated at any firing rate lower than the maximum capacity, there is a possibility to
have too much excess air. See Figure 8.
1. To decrease excess air,
loosen the nut on the air orifice
plate and slide it inward.
2. To increase excess air, slide it
outward.
The VA series burner is designed
to operate as low as 1% O2(5%
excess air). It is not recommended
to adjust the excess air without
using a combustion analyzer.
F - Excess Air
Adjustment
VI Initial
Start-up/Adjustment
Continued
Slide
One Way or
the Other
Loosen the Nut
Figure 8 - Excess Air Adjustment
Part 1 Installation
__________________________________________
1. Check the operation of the burner; start and stop it several times with the operating control.
2. With the burner running, check the operation of all limit and associated controls.
3. Perform the following final adjustments for combustion and flue gas temperature. Take the flue
gas samples and temperature immediately upstream of the draft control. Generally, the flue gas
temperature should be above 325°F but not exceeding 550°F. Excessive flue gas temperatures will
result in low efficiencies. Low flue gas temperature may cause excessive condensation. Reset gas
input, if necessary, to adjust stack temperature.
4. Check the draft control, if equipped, to make sure there is no spillage of flue products into the
room.
5. Fill out the installation adjustment data tag and affix to the burner or gas utilization equipment.
NOTE: For subsequent normal starting and shut offprocedure, refer to CONSUMER
INSTRUCTIONS, located in Section XX of this manual, or to the instruction plate mounted
on the burner.
__________________________________________
- Use a combustion analyzer to confirm that the high fire oxygen (O2) level is between
3.0 to 5.0% and the carbon dioxide (CO2) level is between 8.5 to 10.0%. The carbon
monoxide (CO) should be less than 100 ppm corrected to 3% O2while the flue gas
temperature should be below 550° F.
- Confirm that at low fire the oxygen level is between 16.0 to 18.5% and the carbon
monoxide (CO) level is less than 400 ppm corrected to 3% O2.
_____________________________________
- Remove call for heat (open heat enable contact).
- Close main supply gas valve, see Figure 3 - item # 2 page 4.
- Turn offmain power disconnect and burner control panel switch.
- Remove pressure tap fittings and gauges for pressure measurements. Replace pipe plugs.
- Reinstall the caps to the pilot regulator, main regulator, low-fire bypass and ratio regulator.
_____________________________________
- Open all manual gas valves
- Turn on power at disconnect switch
- Turn on power switch on burner control panel door
- Set heat enable and temperature controller to desired operating condition and temperature
- Burner will start and operate based on 2 to 10V DC analog input provided
_____________________________________
G- Final Checks
VII Check Emissions
24V Burners
VIII Shut Downs
24V Burners
I X Normal
Operations
24V Burners

17
Midco International Inc.
8471 95
WARNING: Explosion hazard. Do not use any electronic device if it gets wet.
It can malfunction and cause serious injury or death. Replace any device that
has been wet.
DANGER: Do not tamper with the unit or controls. If trouble occurs contact the
installing contractor, service agency, or fuel supplier. See front cover.
DANGER: Be sure that the main and pilot manual Shut-OffValves are closed and
the burner power supply is turned offbefore removing any parts for service.
__________________________________________
The air-fuel modulation is achieved through the relationship of the supplied air pressure and the
output gas pressure. The motor used in this burner is variable speed. By using this air pressure
relation in the blower, output gas pressure can be varied relative to the air pressure through a ratio
regulator.
Refer to Figure 9- (see page 29) which shows air pressure pickup at the blower outlet. The air
sensing tube is connected to the ratio regulator. When the blower is modulating to a certain speed,
the pressure in the housing causes the ratio regulator to open. It is a linear relationship between
the air pressure and the gas pressure. The temperature control or operating control sends a heat
input signal (2-10 VDC) to the blower; as a result, the blower pressure causes the gas to modulate
through the ratio regulator.
__________________________________________
!
Part 2 - Service - SCEBM-2 Module
!
!
X Modulation
Methodology
Part 2 Service - SCEBM-2 Module

18 Midco International Inc. 8471 95
Part 2 Service - SCEBM-2 Module 120V
When there is a call for heat, 120V is supplied to the burner; the burner will go through its
pre-purging sequence. The blower will accelerate to the highest speed and at that point it will stay
at the highest speed for 30 seconds. After 30 seconds, the blower will decelerate to the lowest
speed. At the same time the ignition controller will initiate the ignition of the pilot. Once the pilot
flame is established, the main flame will turn on, and at the same time the heat input signal can
now modulate the burner. Refer to Chart 4 and Chart 5 for the sequence of operation.
XI Burner Sequence
of Operation
for 120V Burners
A Intermittent
Sequence Version
120V Burners
Chart 4 - Intermittent 120-V Sequence of Operation
Call for heat/Burner is Energized
Pre-purging sequence initialized:
• Relay “A” is energized
• SCEBM-2 Control will read “PRGE”
• Blower accelerates to high speed
• Low pressure air switch is closed
Pre-purging:
• Blower achieved high speed
• High pressure air switch is closed
• Flame safeguard is initialized and begins 30 second pre-purge
0
30
31
Pilot initialization:
• Flame safeguard initializes pilot flame for 10 seconds trial for ignition
• Pilot valve opened and spark initialized
• SCEBM-2 Control will read “PIL”
• Blower decelerates to lowest speed
45 or earlier
Lockout
• Relay “A” is de-energized
• SCEBM-2 Control will read “OFF”
• Blower stops
No
Did the pilot flame light?
Yes
Lighting the main flame:
• Flame safeguard initializes main valve
• Main flame established at low fire
• SCEBM-2 Control will read “RUN”
• Burner begins modulating based on 2-10 VDC modulating signal
Heat Satisfied:
• Operating control opens
• All components shut off
• SCEBM-2 control will read “OFF”
END
Time Line in Seconds
For 120V Models: Intermittent

19
Midco International Inc.
8471 95
Part 2 Service - SCEBM-2 Module 120V
XI Burner Sequence
of Operation
for 120V Burners
Continued
B Interrupted
Sequence Version
120V Burners
END
45 or earlier
30
(30 second default)
31
0
Time Line in Seconds
Call for heat/Burner is Energized
Pre-purging sequence initialized:
• Relay “A” is energized
• SCEBM-2 Control will read “PRGE”
• Blower accelerates to high speed
• Low pressure air switch is closed
Pre-purging:
• Blower achieved high speed
• High pressure air switch is closed
• Flame safeguard is initialized and begins pre-purge
Pilot initialization:
• Flame safeguard initializes pilot flame for 10 seconds trial for ignition
• Pilot valve opened and spark initialized
• SCEBM-2 Control will read “PIL”
• Blower decelerates to lowest speed
Did the pilot flame light?
• Lockout
• Relay “A” is de-energized
• SCEBM-2 Control will read “OFF”
• Blower stops
Lighting the main flame:
• Flame safeguard initializes main valve
• Main flame established at low fire
• SCEBM-2 Control will read “IGN”
Heat Satisfied:
• Operating control opens
• All components shut off
• SCEBM-2 control will read “OFF”
Yes
No
Modulation:
• Flame safeguard de-energizes pilot valve
• SCEBM-2 control will read “RUN”
• Burner begins modulating based on 2-10 VDC control signal
For 120V Models: Interrupted
__________________________________________
Chart 5 - Interrupted 120V Sequence of Operation

20 Midco International Inc. 8471 95
Part 2 Service - SCEBM-1 Module 24V
XII Burner Sequence
of Operation
for 24V Burners
For 24V Models: Intermittent
Chart 6 - 24V Sequence of Operation
END
45 or earlier
30
31
0
Time Line in Seconds
Call for Heat/Burner is Energized
Sequence initialized
• Pre-purging electronics initialized
• Blower receives power
Pre-purging sequence initialized
• SCEBM-1 Control will flash red
• Blower accelerates to high speed
• Low pressure air switch is closed
Pre-purging
• Blower achieved high speed
• High pressure air switch is closed
• Honeywell S8760J is initialized and begins 30 second pre-purge
Pilot initialization
• Honeywell S8760J initializes pilot flame for 15 second trial for ignition
• Pilot valve opened and spark initialized
• SCEBM-1 Control will shine solid red
• Blower decelerate to lowest speed
Did the pilot flame light?
• Lockout
• Blower accelerates to highest speed
• Burner must be de-energized and be
re-energized in order to re-try ignition
• SCEBM-1 Control LED Light will flash
red
Lighting the main flame
• Honeywell S8760J initializes main valve
• Main flame established at low fire
• SCEBM-1 Control will shine solid green if DC signal is above 2 DCV
• Burner begins modulating based on 2-10 VDC modulating signal
Heat Satisfied
• Operating control opens
• All components shut off
Yes
No
__________________________________________