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9. 1To restart system, follow lighting instructions in the
Operation section.
10. 1Check to see that the high limit control is set above
the design temperature requirements of the system.
For multiple zones: Check to make sure the flow is
adjusted as required in each zone.
11. 1Check that the heater is cycled with the thermostat.
Raise the setting on the thermostat to the highest
setting and verify that the heater goes through the
normal start-up cycle. Reduce to the lowest setting
and verify that the heater goes off.
12. 1Observe several operating cycles for proper
operation.
13. 1Set the heater thermostat to desired temperature.
14. 1Review all instructions shipped with this heater
with owner or maintenance person, return to
envelope and give to owner or place the instructions
inside front panel on heater.
7. OPERATION
7.1. Lighting Instructions
1. Before operation, make sure you have read all of the
safety information in this manual.
2. Remove upper front panel.
3. Set the thermostat to the lowest setting.
4. Turn off all electrical power to the appliance.
5. This appliance is equipped with an ignition device
which automatically lights the burner. Do not try to
light the burner by hand.
6. Turn on main manual gas valve field-installed near
gas inlet connection on back of heater.
7. Wait 5 minutes to clear out any gas. Then smell for
gas, especially near the floor. If you then smell gas,
STOP! Follow the steps in the safety information on
the front cover of this manual. If you do not smell
gas, go to next step.
Turn on all electrical power to the appliance.
Set thermostat to desired setting. The appliance will
operate. The igniter will glow after the pre-purge time
delay (15 seconds). After igniter reaches temperature
(30 seconds) the main valve should open for a
4-scond trial for ignition. System will try for ignition
up to three times (one time on optional single-try
ignition module). If flame is not sensed, lockout will
commence.
8. If the appliance will not operate, follow the
instructions “To Turn Off Gas To Appliance”, and call
your service technician or gas supplier.
9. Replace upper front panel.
10. 1If heater fails to start, verify the following:
a. There are no loose connections or that the
service switch is off or in the powered, but
disabled position.
b.
High temperature limit switch (optional) is set
above water temperature or manual reset high
limit is not tripped.
c. Enable/Disable circuit is closed.
d. Gas is on at the meter and the heater.
e. Incoming dynamic gas pressure to the gas
valve is NOT less than 4.0" WC for natural gas or
propane gas.
7.2.
To Turn Off Gas To Appliance
1. Shut off manual gas valve field installed near gas
inlet connection on back of heater.
2. Remove upper front panel.
3. Move 3-position rocker switch to "OFF" position.
4. Turn off all electrical power to the appliance if
service is to be performed.
5. Replace access panel.
8. TROUBLESHOOTING
8.1.
XTherm Error Codes
If any of the sensors detect an abnormal condition or
an internal component fails during the operation of the
XTherm, the display may show the error. This code may
either be the result of a temporary condition in which
case the display will revert to its normal readout when
the condition is corrected, or it may be the result of a
condition that the controller has evaluated as not safe to
restart the unit. In this case, the unit control will be locked
out, requiring the maintenance person to manually reset
the control by pressing and releasing the RESET key.
8.2. Heater Errors
When an error condition occurs, the controller will display
an error code on the touch screen display. These error
codes and several suggested corrective actions are
included in the XTherm Fault Text section on the following
page. See
Table Z
and
Table AA.
