Aerco Benchmark G-00-711, Руководство пользователя

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TROUBLESHOOTING
8-5
8. If there is no continuity in one or more of the
wires above, check for loose connectors on
the wires and check the pins of 1 ¾"
connector for proper insertion and/or wear.
9. Reconnect all wires and connectors and
reapply AC power to the unit.
10. If the over temperature fault persists, consult
your local AERCO representative or
qualified service technician.
8.4.3 OTHER CAUSES
While incorrect temperature switch settings or
faulty wiring or connectors can result in water
temperature faults, there are several other
factors that can result in the boilers water
temperature exceeding it’s water temperature
limit of 210 degrees. These include
1. Incorrect settings of PID control settings on
the boilers temperature controller.
The PID settings are located in the
Secondary menu of the boiler’s temperature
controller. Default values for this can be
found in Appendix B of this manual. The
settings to check are pb1, Int, and Drt.
NOTE:
Incorrect PI D settings will only affect
boilers in Constant Setpoint or Indoor /Outdoor
Reset Modes of operation
2. Incorrect or varying flow rates through the
boiler(s). Check to ensure that the minimum
flow rate through the Benchmark is not less
than 25 GPM. In addition if variable speed
pumping or two-way valve systems are
used, fast flow rate changes can result in
over-temperature conditions. It may be
necessary to slow the rate at which flows
vary or to limit the minimum system flow
rate. If over-temperature conditions persist,
contact an authorized AERCO
representative.
3. Not interlocked to an external Energy
Management System (EMS). The EMS
system may be controlling system pumps
and may not be sending a stop start signal
to the AERCO boilers or BMS when the
system pumps are not running.
4. If the boilers are being controlled by an
AERCO Boiler Management System (BMS),
the BMS may require tuning to the loop or
the header sensor may be incorrectly
installed. When setting up a BMS the HDR
TEMP BW should be changed from 50 to
70. This will slow the rate at which the
boilers ramp up resulting in less temperature
overshoot at each individual boiler.
When checking the header sensor, ensure
that the sensor well is not bushed too far out
of the supply header. Also, ensure that the
actual sensing element that goes into the
well is fully extended out of its electrical
housing box as it can slip up into the
electrical housing. The use of conductive
grease in the sensor well is also
recommended to aid in sensor response
time. All the above can affect response time
of the sensor to the BMS. A slow response
time of the sensor to the BMS especially in a
varying flow system can result in high water
temperature faults on one or more of the
boilers.
5. If all or some of the above conditions exist
and have been checked and tried and over
temperature faults still persist contact your
local AERCO representative.
If one of the above is suspect contact your local
AERCO representative for further assistance
8.5 LOCK OUT RUN FLAME
A LOCKOUT RUN FLAME message indicates
that the flame signal was lost after the unit
proved flame and was released to modulate. A
FLAME FAULT DURING IGN TRIAL message
indicates that flame was not recognized during
the ignition trial period.
8.4.1 Flame Fault While Firing
8.4.2 Flame Fault During Ignition Cycle
8.4.3 Safety Shut-Off Valve
8.4.4 Spark Ignitor
8.4.5 Flame Detector
8.4.6 Ignition Circuit
8.4.7 Air Fuel Valve Ignition Position Switch
8.4.8 Flame Detector Voltage
8.4.9 Residual Flame
Recommended Troubleshooting Equipment
•
Digital or Analog Voltmeter
• Combustion Analyzer
• 8” and 16” Manometers
8.5.1 FLAME FAULT WHILE FIRING
1. If the combustion control has a keyboard
display module installed, the flame signal
can be monitored directly, if not, proceed
with the next step.
2. Install a voltmeter in the flame test jacks
located on the front of the combustion
safeguard and start the unit.