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Start-Up — Indirect Gas-Fired Heating

20

 CLCH-SVX014B-EN

3. Confirm Gas Flow at Unit:

Open door to unit vestibule housing the gas heater. 
Move gas control lever to “OFF” position. Remove 
1/8-in. pressure taps from both modulating and on-off 
sections of the split heater manifold. Install a barbed 
fitting in both 1/8-in. tapped holes for connection to 
individual gas manometers. 

Note:

There is a third 1/8-in. gas pressure tap located 
in the pipe connecting the main valve/regulator 
and modulating valve. Maximum pressure into 
modulating valve is 5-in. The On-Off gas valve 
includes a regulator adjustment device that is 
located on the top of the valve. Use this device 
to regulate valve output to modulating valve as 
required.

4. Wait 5 minutes for any gas to clear. If you smell gas, 

Step 2

 and correct leak. If you don’t smell gas or have 

corrected any leaks, go to the next step.

5. Main Gas Supply:

Turn manual gas cock “ON”.

6. Pre-purge and Ignition:

a. Open all manual gas valves. 

b. Turn power on at the gas heat switch inside the gas 

heat vestibule. 

c. A call for heat is initiated by the AHU unit control 

through a 0-10V analog signal.

d. The heater controller will then go through a system 

check to ensure that the high temperature limit and 
rollout switches are closed, the air pressure switch 
is open, and the modulating valve is positioned 
correctly.

e. The control will then enter the pre-purge cycle, 

where the inducer will run at the programmed 
purge pressure. During this cycle, the control will 
look for the air pressure switch to close and open at 
the correct settings.

f. Once the system check and pre-purge cycles are 

complete, the control will enter the ignition cycle.
The modulating valve and inducer will go to their 
“light off” settings.
The DSI ignition module will be energized and the 
spark ignitor will activate.
The redundant safety valve will open, allowing gas 
flow.
The burners will ignite and the control will receive 
a signal from the flame sensor.
The spark ignitor will remain active for the duration 
of the ignition cycle, regardless of flame status.

g. If flame is not established during the ignition cycle, 

the control will repeat the pre-purge and ignitions 
cycles up to three times. After three failed ignition 
attempts, the board will enter a 1 hour lockout.

h. Once flame has been established, the control will 

enter a warm-up period to ensure flame 

stabilization and reduce condensation in the heat 
exchanger.

i. After the warm-up period, the control will enter the 

run cycle. During the run cycle, the burner firing rate 
and draft inducer pressure are determined based on 
the heat demand received by the control via a 0-10V 
analog signal.

Note:

If the control is paired with a split manifold, 

Step c

 

through 

Step h

 pertain to the primary burners. 

Once the control exits the warm-up period and the 
firing rate is dictated by the rooftop control, the 
control will ignite the secondary burners and 
modulate the primary burners based on the 
demand for heat.

j. The run cycle will continue until any of the following 

conditions are met.

The call for heat is terminated.

Any of the safety devices (high limit, air 
pressure, rollout, etc.) are triggered.

The control reaches it’s maximum run time of 6 
hours. If this condition is reached, the control 
will terminate the run cycle, continue through 
the proper sequence of operations, and then 
immediately enter the system check and pre-
purge cycles to prepare for re-ignition, 
assuming conditions A and B haven't been met.

k. Once the run cycle has terminated, the redundant 

safety valve will close, the modulating valve will 
return to its set position, and the draft inducer will 
ramp up to its “light-off” setting for a 45 second 
post-purge cycle.

l. After the conclusion of the post-purge, the control 

will enter the “OFF” state. All system outputs are 
de-energized but all safety devices are still 
monitored.

m. When the building management system 

temperature is satisfied and the demand for heat 
ends, the gas valve is de-energized immediately 
and the combustion blower is energized on high 
speed for 30-second post-purge period.

n. If the unit fails to ignite see Troubleshooting 

chapter.

Summary of Contents for CSA004

Page 1: ...g Improperly installed adjusted or altered equipment by an unqualified person could result in death or serious injury When working on the equipment observe all precautions in the literature and on the tags stickers and labels that are attached to the equipment Gas Heat Inshot Style Performance Climate Changer CSAA Air Handlers Sizes 4 to 30 for Indoor and Outdoor Units Installation Operation and M...

Page 2: ...uation which if not avoided could result in minor or moderate injury It could also be used to alert against unsafe practices NOTICE Indicates a situation that could result in equipment or property damage only accidents WARNING Proper Field Wiring and Grounding Required Failure to follow code could result in death or serious injury All field wiring MUST be performed by qualified personnel Improperl...

Page 3: ...ers Revision History Updated start up procedure Updated normal sequence of operation Added new chapter Troubleshooting Guide WARNING Follow EHS Policies Failure to follow instructions below could result in death or serious injury All Ingersoll Rand personnel must follow Ingersoll Rand Environmental Health and Safety EHS policies when performing work such as hot work electrical fall protection lock...

Page 4: ...igh Altitude Installations 13 Installing Outdoor Flue Stacks 13 Installing Indoor Flue Stacks 14 Installing Rain Hood Combustion Air Inlet 14 Installing Flue Stack for Hurricane Applica tions 14 Duct Connections 14 Combustion Air Duct 14 Duct Transitions 15 Airflow Direction 15 Piping 16 Gas Piping 16 Proper Gas Pressure 16 Heat Exchanger Condensate Piping 16 Wiring 17 Wiring Checklist 17 High Vol...

Page 5: ...ion and startup difficulties Nameplate Each air handler section includes a nameplate label which identifies the type of section customer tagging information the unit serial number the unit order number the build section position for installation and the unit model number Note The unit serial number and order number is required when ordering parts or requesting service for a Trane air handler Figur...

Page 6: ...___________________ Air Handler Serial Number_________________________________________________________________ Startup Date_______________________________________________________________________________ Altitude Above Sea Level___________________________________________________________________ Calorific Value_____________________________________________________________________________ Maximum Firi...

Page 7: ...s heat section must be in a blow thru position downstream from the supply fan Downstream sections must be separated by a blank access section and discharge temperatures must be controlled so as not to exceed the temperature limits of components in the downstream sections Table 1 Motor and electrical specifications Specifications Gas Heater Input Power Inducer Motor a Control Power a Volts 115 115 ...

Page 8: ...on and must be removed before assembly to the air handler Instruction Manuals Individual instruction manuals for all of the gas train components such as flame control relay valves pressure switches and actuators ship inside the piping vestibule Retain these manual for future repair or troubleshooting Handling The gas heat section is designed with the necessary number of lift points for safe instal...

Page 9: ...ed for units that will be installed indoors However when outdoor storage is necessary several things must be done to prevent damage Note Keep the equipment on the original wooden blocks skid for protection and ease of handling Select a well drainedarea preferably a concrete pad or blacktop surface Place the unit on a dry surface or raised off the ground to assure adequate air circulation beneath t...

Page 10: ... as filter access doors coil piping connections motor locations hoods pipe cabinets etc Sufficient clearance must be provided on all sides of unit for removal of access panels plug panels or section to section attachment brackets Clearance for starters VFDs or other high voltage devices must be provided per NEC requirements For specific dimensional and weight information refer to the unitsubmittal...

Page 11: ...6 636 636 325 74 136 856 008 205 56 636 691 325 74 136 919 405 84 136 1027 010 205 56 636 733 325 74 136 970 405 84 136 1068 012 240 44 386 639 325 57 386 854 485 67 136 997 014 240 44 386 657 325 57 386 875 485 67 136 1021 017 240 44 386 686 325 57 386 910 485 67 136 1060 021 650 66 006 1348 970 81 006 1646 025 650 66 006 1391 970 81 006 1695 030 650 66 006 1453 970 81 006 1767 ...

Page 12: ...y fan providing airflow All wiring must comply with applicable local and National Electric Code NEC specifications For VAV units provide temperature sensors for entering and leaving air in gas heat section WARNING Improper Unit Lift Failure to properly lift unit could result in unit dropping and possibly crushing operator technician which could result in death or serious injury and possible equipm...

Page 13: ... inside the unit once the unit is assembled Installation High Altitude Installations Air fuel adjustment is not normally required However for high altitude installations adjustment to the air fuel may be necessary for proper combustion Heater outputs must be derated four percent for every 1000 feet over 2000 feet above sea level When specifying gas heaters the engineer should provide the MBh and a...

Page 14: ...e of the hood 2 3 8 inches below the bottom edge of the inlet air opening and center the hood left to right over the inlet air opening See the following figure Install the hood to the unit with number 10 screws Installing Flue Stack for Hurricane Applications Note When installing flue leave enough clearance to avoid roof s edge and anything above the roof Duct Connections All duct connections to t...

Page 15: ... through the vestibule is needed to keep the temperatures in the vestibule down Duct Transitions When the gas heat section is the last section of the air handler and duct transitions should be smooth and uniform from all sides Follow recommendations for duct transitions from SMACNA Fasten the ductwork directly to the ductwork opening When using lined ductwork the insulation should not obstruct the...

Page 16: ...ger Condensate Piping Condensate usually does not form in the heat exchanger during normal heating operation However if the unit operates for extended periods of time at very low fire or if the air handler serves as a cooling unit also condensate can form in the heat exchanger and should be removed All units are equipped with a condensate drain The condensate drain is on the same side as the gas t...

Page 17: ...iate Single phase 120 208 230 460 or 575 volt power is required to operate the heater controls or power the transformer TRANS1 if provided Single phase power for 208 230 460 and 575 voltage is provided for the gas heat off two legs of the three phase supply to the air handling unit A transformer in the piping vestibule is provided to step down the voltage required for gas heat WARNING Proper Field...

Page 18: ...p signal is interrupted to the gas heat system if the supply fan is shut off The gas heat system must not operate without the supply fan providing airflow The control system also requires a 0 to 10 Vdc analog signal for modulation where 10 Vdc is a signal for full heat NOTICE Equipment Damage Do not operate the gas heat system without a supply fan providing airflow Operating the gas heat system wi...

Page 19: ...y Fan Failure Switch Operation The supply fan air proving switch is located in the heater electrical control compartment near the top of the heater panel The switch will fail if not proven within 30 seconds of call for indoor fan ON All unit air filters must be clean before proceeding to properly complete this verification Important If the unit air filters are not clean unit performance could be a...

Page 20: ... spark ignitor will remain active for the duration of the ignition cycle regardless of flame status g If flame is not established during the ignition cycle the control will repeat the pre purge and ignitions cycles up to three times After three failed ignition attempts the board will enter a 1 hour lockout h Once flame has been established the control will enter a warm up period to ensure flame st...

Page 21: ...ion in the fan blade or low voltage to draft inducer motor Inspect draft fan assembly and be sure fan blade is secure to motor shaft Check line voltage to heater 1 Flame Sensor Current Check Flame current is the current which passes through the flame from the sensor to ground A flame signal of 0 5 to 1 0 microamp A is marginal For dependable operation a flame signal of greater than 1 0 A is requir...

Page 22: ...filters or restriction of the air inlet or outlet to the unit The high limit switch will automatically reset when the air temperature drops to approximately 50 F below the limit setpoint Determine the cause of the reduced air flow and correct Supply Fan Air Proving Switch A supply fan air proving switch is provided as a part of the gas heat control system to verify air handling unit supply fan air...

Page 23: ... secondary burners and modulate the primary burners based on the demand for heat 8 The run cycle will continue until any of the following conditions are met a The call for heat is terminated b Any of the safety devices high limit air pressure rollout etc are triggered c The control reaches it s maximum run time of 6 hours If this condition is reached the control will terminate the run cycle contin...

Page 24: ...24 CLCH SVX014B EN Wiring Diagrams Figure 12 Typical wiring diagram for 5 1 turndown heater ...

Page 25: ...Wiring Diagrams CLCH SVX014B EN 25 Figure 13 Typical wiring diagram for 10 1 turndown heater ...

Page 26: ...Wiring Diagrams 26 CLCH SVX014B EN Figure 14 Typical wiring diagram for 20 1 turndown heater ...

Page 27: ...l electric power including remote disconnects before servicing Follow proper lockout tagout procedures to ensure the power can not be inadvertently energized WARNING Hazard of Explosion Failure to follow proper safe leak test procedures could result in death or serious injury or equipment or property only damage NEVER use an open flame to detect gas leaks You MUST use a leak test solution for leak...

Page 28: ...t tagout procedures to ensure the power can not be inadvertently energized When necessary to work with live electrical components have a qualified licensed electrician or other individual who has been trained in handling live electrical components perform these tasks WARNING Hazardous Gases and Flammable Vapors Failure to observe following instructions could result in death or serious injury Expos...

Page 29: ...tch failed to open 1 Failed combustion blower 2 Check pressure hoses for leaks or blockage 3 Check for blockage in the inducer barb fitting 4 Check for condensate accumulation in the pressure switch and hose 5 Check the pressure switch wiring 6 Replace the pressure switch E05 29 Air pressure sensor reading high and or pressure switch failed to close 1 Check wiring to the pressure switch and draft ...

Page 30: ...here is no voltage to gas valve repair replace wiring if voltage is present 2 If voltage is not present check for gas flow If gas is flowing verify line and manifold pressures before replacing valve eAIR_FLOW_LOW eAIR_FLOW_HIGH 43 44 Low pressure switch is open High pressure switch is open 1 Failed combustion blower 2 Check pressure hoses for leaks or blockage 3 Check for blockage in the inducer b...

Page 31: ...pertain to the primary burners Once the control exits the warm up period and the firing rate is dictated by the rooftop control the control will ignite the secondary burners and step High or Low the primary burners based on the demand for heat 8 The run cycle will continue until any of the following conditions are met a The call for heat is terminated b Any of the safety devices high limit air pre...

Page 32: ...and protect food and perishables and increase industrial productivity and efficiency We are a global business committed to a world of sustainable progress and enduring results ingersollrand com Ingersoll Rand has a policy of continuous product and product data improvement and reserves the right to change design and specifications without notice We are committed to using environmentally conscious p...

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