Aerco Benchmark G-00-711, Руководство пользователя

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TROUBLESHOOTING
8-2
wires #152 & #153 from the low gas
pressure switch.
2. Using an ohmmeter, check the gas pressure
switch for continuity. Be sure the gas supply
to the unit is on and that the static pressure
is above 6” W.C. and reset the manual rest
gas pressure by depressing the reset button
prior to checking continuity.
3. Replace the low gas pressure switch if it
does not show continuity.
4. If the switch shows continuity, locate and
remove wire #116 from the temperature
switch located on the unit’s shell. Check for
continuity from wire #116 to wire #153. Next,
locate and remove wire #64 from the low
water cut-off circuit board located inside the
control box. Measure for continuity from wire
#64 to wire #152 at the low gas pressure
switch.
Note: The procedures in step 4 test and
ensure the integrity of wiring inside and
outside of the control panel as well as the
connections of the control box connectors.
5. If there is no continuity, check for loose
connectors at the switch end of the wires.
Check the pins in the 1” diameter connector
on the bottom of the control box for proper
insertion and/or signs of wear. Make any
necessary repairs.
6. If the wires and connectors are not
defective, reconnect them. Reconnect
electric power.
7. If the gas pressure fault still does not clear it
will be necessary to troubleshoot the control
panel. Contact a qualified service technician
or your local AERCO representative for
more information.
8.2 HIGH GAS PRESSURE
A HIGH GAS PRESSURE message indicates
that gas pressure has exceeded 20” W.C.,
tripping the high gas pressure switch.
Recommended Troubleshooting Equipment
• 16” Manometer
• Analog or Digital Ohmmeter
1. Install a manometer in the unit’s gas supply
manifold as per Section 4.2.2. of this
manual.
2. Check the static pressure to the unit. It
should be between 9” to 14” W.C.
3. If the static pressure to the unit is higher
than 14” readjust the supply regulator until
it’s output is less than 14” W.C.
4. Start the unit and raise the firing rate in 10%
increments. If gas pressure is less than 7”
W.C. after reaching 100% input percentage,
readjust the gas the gas pressure to 7”. (It
may be necessary to depress the high gas
pressure switches manual reset button prior
to restarting the unit.)
5. Next, lower the input percentage to shut the
unit down. Measure the static gas pressure.
If it is above 14” it is an indication that there
may be excessive pressure drops in the gas
supply piping or other components in the
gas supply system.
6. If gas pressure did not require adjustment
and is higher than 14” W.C, it may be
necessary to replace the gas supply
regulator with a lock up style. Consult your
local AERCO representative for more
information.
8.2.3 HIGH GAS PRESSURE SWITCH
1. If static pressure to the unit is correct,
disconnect AC power to the unit. Remove
wires #151 & #150 from the high gas
pressure switch.
2. Using an ohmmeter, check the gas pressure
switch for continuity. Be sure the gas supply
to the unit is on and that the static pressure
is less than 20” W.C. If the unit has a
manual reset gas pressure switch, be sure
to depress the reset button prior to checking
continuity.
3. Replace the high gas pressure switch if it
does not show continuity.
4. If the switch shows continuity, remove wires
#150 and #151 from the temperature switch.
Locate wire #118 on the low water cut-off
board located inside the control box. Check
for continuity between wire #118 and wire
#151. Next locate and remove wire #55.
Wire #55 is located at the interlocks on the
top left-hand side of the control panel door.
Check for continuity between wire #55 and
wire #150.