CaptiveAire D76 User manual

Compact Direct Fired Heaters
Installation, Operation, and Maintenance Manual
FOR YOUR SAFETY
IF YOU SMELL GAS: OPEN WINDOWS, DO NOT TOUCH ELECTRICAL SWITCHES, EXTINGUISH
ANY OPEN FLAMES, IMMEDIATELY CALL YOUR GAS SUPPLIER.
FOR YOUR SAFETY
THE USE AND STORAGE OF GASOLINE OR OTHER FLAMMABLE VAPORS AND LIQUIDS IN
OPEN CONTAINERS IN THE VICINITY OF THIS APPLIANCE IS HAZARDOUS.
RECEIVING AND INSPECTION
Upon receiving unit, check for any interior and exterior damage. If damage is found, report it
immediately to the carrier. Check that all accessory items are accounted for and are not
damaged.
WARNING!!
Improper installation, adjustment, alteration, service or maintenance can cause property
damage, injury or death. Read the installation, operating and maintenance instructions
thoroughly before installing or servicing this equipment. ALWAYS disconnect power and gas
prior to working on heater.
Save these instructions. This document is the property of the owner of this equipment and is required
for future maintenance. Leave this document with the owner when installation or service is complete.
A0011029
May 2020 Rev. 15

2

3
Table of Contents
WARRANTY ............................................................................................................................................................................. 4
INSTALLATION ........................................................................................................................................................................ 5
Mechanical ........................................................................................................................................................................... 5
Curb and Ductwork ............................................................................................................................................................... 7
Roof Mount Installation ......................................................................................................................................................... 8
Gas ....................................................................................................................................................................................... 9
ELECTRICAL .......................................................................................................................................................................... 11
Fan to Building Wiring Connection ..................................................................................................................................... 12
Motorized Intake Damper ............................................................................................................................................... 13
Permanent Split Capacitor (PSC) Motor Speed Control .................................................................................................... 13
EVO™/ECM-VCU .......................................................................................................................................................... 13
Electronically Commutated Motor (ECM) Speed Control ................................................................................................... 14
External PWM Signal ..................................................................................................................................................... 14
Unit Mount Controller ......................................................................................................................................................... 14
Motor Speed Controller (MSC) Installation ......................................................................................................................... 15
MSC Controls Overview ..................................................................................................................................................... 16
MSC Menu ..................................................................................................................................................................... 16
Input Threshold .............................................................................................................................................................. 18
MSC Menu Tree ............................................................................................................................................................. 19
Remote Control Panel ........................................................................................................................................................ 20
Motorized Intake Damper ................................................................................................................................................... 20
Electric Cabinet Heater ...................................................................................................................................................... 20
Variable Frequency Drive (VFD) ........................................................................................................................................ 21
Variable Frequency Drive (VFD) Installation .................................................................................................................. 22
Input AC Power .............................................................................................................................................................. 22
VFD Output Power ......................................................................................................................................................... 22
VFD Programming ......................................................................................................................................................... 23
ACTECH SMV VFD ....................................................................................................................................................... 24
OPERATION ........................................................................................................................................................................... 25
Start-up Procedure ............................................................................................................................................................. 25
Pilot Adjustment ................................................................................................................................................................. 26
Main Burner Adjustment ..................................................................................................................................................... 27
Final Start-up Procedure ................................................................................................................................................ 28
Pulley Adjustment ............................................................................................................................................................... 29
Pulley Alignment/Proper Belt Tension ................................................................................................................................ 30
Pulley Combination Chart ................................................................................................................................................... 31
Sequence of Operation ...................................................................................................................................................... 32
Flame Safety Control ..................................................................................................................................................... 32
Modulating Gas System ..................................................................................................................................................... 34
High Temperature Limit ...................................................................................................................................................... 34
Optional Remote Panel Circuit ........................................................................................................................................... 35
Remote Panel Option .................................................................................................................................................... 36
Troubleshooting .................................................................................................................................................................. 37
Burner Troubleshooting ..................................................................................................................................................... 38
Remote Panel Troubleshooting Chart ............................................................................................................................ 39
MSC Troubleshooting .................................................................................................................................................... 40
MAINTENANCE ...................................................................................................................................................................... 41
General Maintenance ......................................................................................................................................................... 41
2 Weeks After Start-up ....................................................................................................................................................... 41
Every 3 Months .................................................................................................................................................................. 41
Yearly ................................................................................................................................................................................. 41
Burner Maintenance ...................................................................................................................................................... 42
Re-Setting of the Unit .................................................................................................................................................... 42
Emergency Shutdown of Unit ........................................................................................................................................ 42
Prolonged Shutdown of the Unit .................................................................................................................................... 42
Start-Up and Maintenance Documentation ........................................................................................................................ 44

4
WARRANTY
This equipment is warranted to be free from defects in materials and workmanship, under normal use and
service, for a period of 2-years from date of shipment. This warranty shall not apply if:
1. The equipment is not installed by a qualified installer per the MANUFACTURER’S installation
instructions shipped with the product.
2. The equipment is not installed in accordance with Federal, State, Local codes and regulations.
3. The equipment is misused or neglected, or not maintained per the MANUFACTURER’S maintenance
instructions.
4. The equipment is not installed and operated within the limitations set forth in this manual.
5. The invoice is not paid within the terms of the sales agreement.
The MANUFACTURER shall not be liable for incidental and consequential losses and damages potentially
attributable to malfunctioning equipment. Should any part of the equipment prove to be defective in
material or workmanship within the 2-year warranty period, upon examination by the MANUFACTURER,
such part will be repaired or replaced by MANUFACTURER at no charge. The BUYER shall pay all labor
costs incurred in connection with such repair or replacement. Equipment shall not be returned without
MANUFACTURER’S prior authorization, and all returned equipment shall be shipped by the BUYER,
freight prepaid to a destination determined by the MANUFACTURER.

5
INSTALLATION
It is imperative that this unit is installed and operated with the designed airflow and electrical supply in
accordance with this manual. If there are any questions about any items, please call the service
department at 1-866-784-6900 for warranty and technical support issues.
Mechanical
WARNING: DO NOT RAISE UNIT BY THE INTAKE HOOD, BLOWER, MOTOR SHAFT, OR
BEARINGS. USE ALL LIFTING LUGS PROVIDED WITH A SPREADER BAR OR SLING UNDER THE
UNIT.
Figure 1 - Spreader Bar
Site Preparation
1. Provide clearance around installation site to safely rig and
lift equipment into its final position (Figure 1). Supports
must adequately support equipment. Refer to
manufacturer’s estimated weights.
2. Locate unit close to the space it will serve to reduce long,
twisted duct runs.
3. Consider general service and installation space when
locating unit.
4. Do not allow air intake to face prevailing winds. Support
unit above ground or at roof level high enough to prevent
precipitation from being drawn into its inlet. The inlet must
also be located at least 10 feet away from any exhaust
vents. The fan inlet shall be located in accordance with the
applicable building code provisions for ventilation air.
Clearance
The top, back, and front surfaces of this heater may not be installed less than 6” from combustible
materials. The heater base may be installed on combustible surfaces. Allow 24” minimum service
clearance on both sides of this heater.
Spreader
Bar
Lifting Lugs
Lifting Lugs

6
Intake Assembly
Intakes and curbs (Figure 2) are shipped on a separate skid. Upon unit arrival, perform the following steps
to assemble the intake to the unit.
1. Apply silicone or weather-proof gasket on the backside of the flanges of the intake hood or V-bank
intake.
2. Secure the flanges of the intake hood to the unit with the supplied sheet metal screws.
3. Use caulk on the outside of the screws to prevent water leaks.
Figure 2 - Intake and Curb Assembly
123
4
1. Blower/Motor Access Door
2. Filtered Intake
3. Screened Intake
4. Curb

7
Curb and Ductwork
This fan was specified for a specific CFM and static pressure. The ductwork attached to this unit will
significantly affect airflow performance. When using rectangular ductwork, elbows must be radius throat,
radius back with turning vanes. Flexible ductwork and square throat/square back elbows should not be
used. Any transitions and/or turns in the ductwork near the fan outlet will cause system effect. System
effect will drastically increase the static pressure and reduce airflow.
•Table 1 shows the minimum fan outlet duct sizes and straight lengths required for optimal fan
performance.
• Do not use the unit to support ductwork in any way. This may cause damage to the unit.
•Follow SMACNA standards and manufacturer's requirements for the duct runs. Fans designed
for rooftop installation should be installed on a prefabricated or factory-built roof curb.
• Follow curb manufacturer’s instructions for proper curb installation.
• The unit should be installed on a curb and/or rail that meets local code height requirements.
• Make sure the duct connection and fan outlet are properly aligned and sealed.
• Secure fan to curb through vertical portion of the ventilator base assembly flange. Use a minimum of
eight (8) lug screws, anchor bolts, or other suitable fasteners (not furnished). Shims may be required
depending upon curb installation and roofing material.
• Verify all fasteners are secure. Figure 3 and Figure 4 show different mechanical installations.
• Adequate building relief shall be provided so as not to over pressurize the building when the heating
system is operating at its rated capacity. This can be accomplished by taking into account, through
standard engineering methods, the structure’s designed infiltration rate; by providing properly-sized
relief openings; or by interlocking a powered exhaust system; or by a combination of these methods.
• Heaters installed with intake ductwork must be purged to replace at least four air changes of the
volume of the intake duct.
• If the failure or malfunction of this heater creates a hazard to other fuel-burning equipment in the
building (e.g., when the heater is providing makeup air to a boiler room), the unit is to be interlocked to
open inlet air dampers or other such devices.
• On outdoor installations, it is recommended that the discharge duct be insulated to prevent
condensation during the “OFF” cycle in cold weather.
• Flexible connectors should be used on all ductwork connections. Vibration isolators are optional and
can be supplied in the loose parts package.
• Units that are installed in airplane hangars should be installed in accordance with the Standard for
Aircraft Hangars, ANSI/NFPA 409. Units that are to be installed in public garages should be installed in
accordance with the Standard for Parking Structures, ANSI/NFPA 88A, or the Standard for Repair
Garages, ANSI/NFPA 88B, and with CAN/CGA B149 Installation Codes.
Table 1 - Required Supply Ductwork
Duct Size Straight Duct Length
12” x 12” 36”

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Roof Mount Installation
Note: Refer to submittal drawings for specific unit dimensions.
Figure 3 - Roof Mount Installation Details
Figure 4 - Indoor Inline
1
AIRFLOW
2
3
4
5
6
9
8
7
10
1. Discharge Opening
2. Curb Outer Wall
3. Flex Conduit for Field Wiring
4. Screened Intake
5. Filter Access Door
6. Service Disconnect Switch
7. 1/2” NPT Pipe
8. Blower/Motor Access Door
9. Control Drop
10. Motor Drop
1. Service Disconnect Switch
2. 1/2” NPT Pipe
3. Optional Unistrut Base for
Hanging
A. 1” Spacing from Unistrut to edge
of unit
B. 36” Unistrut
C. Unit Height
AIRFLOW
MOTOR
BLOWER/
DOOR
ACCESS
A
1
B
2
3
A
C

9
Gas
Installation of gas piping must conform with local building codes, or in the absence of local codes to the
National Fuel Gas Code, ANSI Z223.1 (NFPA 54) – latest edition. In Canada, installation must be in
accordance with CAN/CGA-B149.1 for natural gas units and CAN/CGA-B149.2 for propane units.
WARNING: INLET GAS PRESSURE MUST NOT EXCEED PRESSURE INDICATED ON NAMEPLATE.
SEE UNIT NAMEPLATE FOR PROPER GAS SUPPLY PRESSURE AND GAS TYPE.
1. Always disconnect power before working on or near a heater. Lock and tag the disconnect switch or
breaker to prevent accidental power-up.
2. Piping to the unit should conform to local and national requirements for type and volume of gas
handled, and pressure drop allowed in the line. Refer to the Gas Engineer’s Handbook for gas line
capacities.
3. The incoming pipe near the heater should be sized to match the connection on the outside of the unit.
Unit inlet sizes are shown in Table 2. The unit requires a steady supply of gas at all times, avoid
multiple taps in the gas supply line.
4. Install a ground joint union with brass seat and a manual shut-off valve external to the unit casing.
Install shut-off valve adjacent to the unit for emergency shut-off and easy servicing of controls. Refer to
Figure 5.
5. Provide a sediment trap, as shown in Figure 5, before each unit and where low spots in the pipeline
cannot be avoided.
6. Clean out the gas line to remove debris before making connections. Purge gas line to remove air
before attempting to start unit. Purging air from gas lines should be performed as described in ANSI
Z223.1-latest edition “National Fuel Gas Code,” or in Canada as described in CAN/CGA-B149.
7. All field gas piping must be pressure/leak tested before unit operation. Use a non-corrosive bubble
forming solution or equivalent for leak testing. The heater and its individual shut-off valve must be
disconnected from the gas supply piping system during any pressure testing of that system at test
pressures in excess of 1/2 psi.
8. This unit requires the gas pressure to be within the unit’s minimum and maximum gas pressure
ratings. If the pressure is greater than the maximum, the internal valve components will be damaged. If
the pressure is below the minimum, the heater will not perform to specifications. Refer to Table 3 on
page 10.
Table 2 - Gas Connection Sizes
Unit Size Gas Pipe Size (NPT)
76 1/2”

10
Figure 5 - Gas Connection Diagram
Table 3 - Gas Pressure
Gas Pressure Type Gas Pressure
Natural/LP 5 - 14 Inches WC Maximum
NOTICE
Refer to the heater’s rating plate for determining gas supply pressures and requirements.
1
12
3
4
5
A
1. Gas Supply Line Connection
2. Manual Gas Shut-off Valve
3. Ground Joint Union with Brass Seat
4. Plugged 1/8” NPT Test Gauge Connection
5. Sediment Trap
A. Minimum Depth = 3”