Maxi Comet Executive Exec-56-G, Инструкция по эксплуатации

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S8600, S8610, S8660, S8670 INTERMITTENT PILOT MODULE
13 69-0463—01
control system must be reset by setting the thermostat
below room temperature for one minute or by turning off
power to the module for one minute.
Safety Shutoff with Continuous Retry (S8600M)
The S8600M provides 100 percent gas shutoff, followed
by retry for ignition. Operation on ignition failure is the
same as lockout modules, except that a timer starts timing
immediately following shutoff. Six minutes nom. (five
minutes min.) after shutoff, the module restarts the
ignition sequence. The ignition trial, shutoff, wait
sequence continues until either the pilot lights or the
thermostat is set below room temperature to end the call
for heat. The module can also be reset by setting down
the thermostat for one minute.
Main Burner Operation
When the pilot flame is established, a flame rectification
circuit is completed between the sensor and burner
ground. The flame sensing circuit in the module detects
the flame current, shuts off the spark generator and
energizes the second main valve operator. The second
main valve opens and gas flows to the main burner,
where it is ignited by the pilot burner. On lockout models,
the flame current also holds the safety lockout timer in the
reset (normal) operating condition.
When the call for heat ends, both valve operators are
de-energized, and both valves in the gas control close.
Fig. 12. S8660, S8670 Normal Operating Sequence.
TROUBLESHOOTING
IMPORTANT
1. The following service procedures are provided
as a general guideline. Follow appliance
manufacturer service instructions, if available.
2. On lockout and retry models, meter readings
between gas control and ignition module must
be taken within the trial for ignition period. Once
the ignition module shuts off, lockout models
must be reset by setting the thermostat down for
at least one minute before continuing. On retry
models, wait for retry or reset at the thermostat.
3. If any component does not function properly,
make sure it is correctly installed and wired
before replacing it.
4. The ignition module cannot be repaired. If it
malfunctions, it must be replaced.
5. Only trained, experienced service technicians
should service intermittent pilot systems.
Perform the checkout on page 11 as the first step in
troubleshooting. Then check the appropriate
troubleshooting guide (Figures 14 or 15) and the
schematic diagram (Figures 16 or 17) to pinpoint the
cause of the problem. If troubleshooting indicates an
ignition problem, see Ignition System Checks below to
isolate and correct the problem.
Following troubleshooting, perform the checkout
procedure again to be sure system is operating normally.
Ignition System Checks
STEP 1: Check ignition cable.
Make sure:
1. Ignition cable does not run in contact with any metal
surfaces.
2. Ignition cable is no more than 36 in. (0.9 m) long.
M1171C
START
THERMOSTAT
PREPURGE
SPARK GENERATOR POWERED
PILOT BURNER OPERATION
OR
Pilot burner lights.
S8660, S8670 senses flame
current.
Pilot burner does not light.
After 15 or 90 sec , system
locks out; must be manually reset.
Lockout timing is
stamped on module.
a
a
STAGE 1
PREPURGE
STAGE 2
TRIAL FOR IGNITION
STAGE 3
MAIN BURNER
OPERATION
END
FLAME CURRENT SENSED
MAIN BURNER OPERATION
Module monitors pilot flame
current.
THERMOSTAT SATISFIED
Valves close, pilot and main
burners are off.
POWER INTERRUPTION
System shuts off, restarts when power is
restored.
PILOT FLAME FAILURE
Main valve closes.
S8660, S8670 starts trial for ignition.
Spark generator off.
Second valve operator (main)
opens.
•
•
1
2
3
4
5
6
7
CALLS FOR HEAT
Combustion air blower starts.
First valve (pilot) operator opens.
69-0463-1.fm Page 13 Wednesday, December 19, 2007 1:22 PM
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