D. Completion
1. Once the proper inlet and burner manifold pres-
sures have been confirmed and/or properly set,
close the fuel supply valve to the heater and allow
the heater to burn off any gas remaining in the gas
supply line.
2. Disconnect the heater from its electrical supply.
3. Remove the gauges and connecting hoses.
4. Install pressure tap plugs and tighten securely.
Check for gas leaks.
Troubleshooting Guide
READ THIS ENTIRE SECTION
BEFORE BEGINNING TO
TROUBLESHOOT PROBLEMS.
WARNING
Electrical Shock and Burn Hazard
■ Troubleshooting this system may require
operating the unit with line voltage present and
gas on. Use extreme caution when working on
the heater.
■ Failure to follow this warning may result in
property damage, personal injury or death.
The troubleshooting flow charts on the following
pages provide systematic procedures for isolating
equipment problems. The charts are intended for
use by a QUALIFIED GAS HEATER SERVICE
PERSON. DO NOT SERVICE THESE
HEATERS UNLESS YOU HAVE BEEN
PROPERLY TRAINED.
TEST EQUIPMENT REQUIRED
The following pieces of test equipment will be
required to troubleshoot this system with minimal
time and effort.
• Digital Multimeter - for measuring AC and
DC voltage and resistance.
• Low Pressure Gauge - (Part No. 00764)
for checking inlet and outlet pressures of the
gas control valve against dataplate rating.
Guardian LP or Natural Gas Heater
INITIAL PREPARATION
■ Visually inspect equipment for apparent damage.
■ Check all wiring for loose connections and worn
insulation.
Refer to the system operation sequence in this section
to gain an understanding as to how the equipment oper-
ates during a call for heat.
Understanding the operation sequence of the ignition
module and related components is
essential as it will relate directly to problem
solving provided by the flow charts.
The ignition control module is self-diagnostic. A solid on
red light indicates normal operation.The red light on the
module will flash a specific pattern if a heater problem
is identified, depending upon the problem which is
diagnosed.
To effectively use the flow charts, you must first identify
what the problem is by the flashing pattern of the red
diagnostic light. If the light is flashing, the flash pattern
will be followed by a pause and then a repeat of the
flash pattern until the problem is corrected.
Refer to the tables below to identify what page to refer
to when troubleshooting any problems.
Diagnostic light not on during a call for heat ...............25
L.E.D. diagnostic light flashing:
A. Rapid Flash ............................................................26
B. Long Flash (2 seconds on - 2 seconds off) ............26
C. One Time ...............................................................26
D. Two Times ..............................................................27
E. Three Times ...........................................................28
F. Four Times ..............................................................28
G. Five Times .............................................................28
H. Six Times ...............................................................28
Components should be replaced only after each step
has been completed and replacement is suggested in
the flow chart.
Owner's Manual • Guardian
23
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