6
Check thermostat circuit(s)
1.Disconnect the two external wires connected to the enable terminals on the connection board.
2.Connect a voltmeter across these two incoming wires. Close each thermostat, zone valve, and relay in the external circuit one at a time and check the voltmeter reading across the incoming wires.
3.There should NEVER be a voltage reading.
4.If a voltage does occur under any condition, check and correct the external wiring. (This is a common problem when using
5.Once the external thermostat circuit wiring is checked and corrected if necessary, reconnect the external thermostat circuit wires to the connection board. Allow the boiler to cycle.
Check vent and air piping
Inspect vent piping and air piping for signs of deterioration from corrosion, physical damage or sagging. Verify air piping and vent piping are intact and correctly installed per this manual.
Placing the boiler in operation
Boiler operational checks
1.Turn the boiler main power switch to the “ON” position.
2.Verify operation of the SMART SYSTEM control module and Operator Interface.
3.Program the adjustable points from the Operator Interface.
4.Push the reset for the low water cutoff (if equipped).
5.Ensure that maximum flow to the boiler does not exceed 55 GPM on Models 402 - 752 and 90 GPM on Models 992 - 2072. Verify by checking temperature rise while burner is firing at 100% of rated input.
6.Install a manometer on the gas supply to the boiler and verify minimum gas supply pressure as the burner fires at 100% of rated input.
7.Verify operation of safeties as necessary (low water cutoff, high limit, gas pressure, etc.,).
8.Verify that all adjustable points in the Operator Interface are set as required.
9.Once the boiler analysis is complete, test the safety shutoff device by turning the manual shutoff valve to the OFF position and ensuring that the boiler shuts down and registers an alarm. Open the manual shutoff valve and reset the control.
10.Place the boiler back into normal operation.
Boiler operation
11.Boiler should begin the
12.The boiler will ignite at the proper ignition speed and will stage to meet the system demand.
13.Ensure that inlet water temperature does not fall below the specified minimum for the boiler.
14.Based on system demand, boilers may run for an extended period of time at a reduced rate of input to maximize efficiency.
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Installation & Operation Manual
15.As system demand is satisfied, the burner will cycle off and the combustion air blower will run for a post purge operation before the boiler shuts down.
Start the boiler
Read and follow the Lighting Instructions in FIG.
If boiler does not start correctly
1.Check for loose connections, blown fuse or service switch off?
2.Is external limit control (if used) open? Is boiler water temperature above 200°F (93.3°C)?
3.Is thermostat set below room temperature?
4.Is gas turned on at meter or boiler?
5.Is incoming gas pressure less than 4.5" water column?
If none of the above corrects the problem, refer to the Troubleshooting Section of the
WARNING The venting system must be installed so that it will prevent flue gas spillage and carbon
monoxide emissions, which will result in severe personal injury or death.
Set space heating operation (boiler only)
Determine controlling sensor
For space heating systems, the temperature control can be based on one of four sensors; the inlet, outlet, system supply sensor, or system return sensor. The SMART SYSTEM control is programmed at the factory to control the temperature of the outlet sensor. The control will automatically switch to the system supply sensor once it is connected. If it is desired to base the temperature control on the inlet sensor, the appropriate parameter must be changed in the control. See the
Verify space heat circulator mode
The Space Heating Mode controls both the system (primary) pump (if connected), and the boiler (secondary) pump. When the SMART SYSTEM control receives a space heating call for heat, it turns on the system pump. If the boiler is not heating an indirect DHW (Domestic Hot Water) tank, it also turns on the boiler pump. After the space heating call for heat ends, the system pump continues to run for a short period of time. If the boiler pump was running, it continues to run for a short period of time as well. These pump delays are factory set to 30 seconds. If different delays are desired, the appropriate parameters in the control must be changed. See the
Set space heating set point temperature
The UP and DOWN keys may be used during normal operation to adjust the space heating set point temperature (see FIG.
