LAARS HWG-M2-250 - Installation, Operation and Maintenance Instructions - Manual (Page 11)

9600 HWG Water Heater Page 11
turn on gas and power and recheck the burner
input.
8. It is recommended that the unit be checked with
a standard CO2 or O2 tester. Insert tester probe
at least 6" into the exhaust pipe through the
outside vent terminal. Readings should be as
follows:
CO2 - 8% to 8.75% natural gas
O2 - 6.9% to 5.5%
CO2 - 9.25% to 9.75% propane gas
NOTE: This is a sealed combustion unit with
the air orifice and gas valve factory set. They
must not be altered or adjusted. If the firing rate
cannot be obtained with the orifices supplied or
if CO2 or O2 readings do not fall within the
above ranges, contact your factory
representative.
9. Using the temperature gauge, check the unit outlet
temperature after three to four minutes of operation.
Minimum operating temperature 160°F.
10. Shutdown instructions.
Turn off all Electrical power to the unit at main
power switch located on Field Wiring Box
cover.
Turn gas cock dial to “off” position.
4.3 Anti-Freeze
Proper precautions for freeze protection are
recommended for boiler installations in areas where
the danger of freezing exists.
Power outage, interruption of gas supply, failure
of system components, activation of safety devices,
etc., may prevent a heater from firing. Any time a
heater is subjected to freezing conditions, and the
heater is not able to fire, and/or the water is not
able to circulate, there is a risk of freezing in the
heater or in the pipes in the system. When water
freezes, it expands. This can result in bursting of pipes
in the system, or damage to the heater, which could
result in leaking or flooding conditions.
Anti-freeze additives, such as glycol, must not be
used in a direct potable water heating system, such as
the HWG.
SECTION 5.
Maintenance
5.1 Owner Care and Maintenance
1. Inspect venting system annually. Inspect the
outside vent terminal fittings to make sure that
they are free of obstructions. Clean if necessary.
2. Inspect the condensate drainage system - this can
be done by removing the screws that secure the
lower front panel to the unit. There should be no
signs of water leakage from any of the visible
fittings or hose (see Figure 9).
3. The pressure relief valve should be operated
manually at least once a year. To do this place a
suitable container under the relief valve drain
pipe. The discharge from this valve will be at
high pressure and temperature. Make sure that
overspray of hot water will not cause damage or
bodily harm. Use the relief valve handle to
discharge water into the container.
NOTE: Do not use this appliance if any part
has been under water. Immediately call a qualified
service technician to inspect the appliance and to
replace any part of the control system and any gas
control which has been immersed.
Keep appliance area clear and free from
combustible materials, gasoline and other flammable
vapors and liquids.
NOTE: There are no moving parts requiring any
lubrication in this unit.
Keep appliance area clear and free of items that
could obstruct ventilation air around the water heater.
SERVICE MAINTENANCE - To be done by
a qualified service person.
5.2 Routine De-Liming Procedure
CAUTION: Use all protective gear and precau-
tions suggested by deliming solution manufacturers.
In hard water areas, this should be done on a
regularly scheduled basis. (If water hardness is over
10 grains, a water softening system must be installed.)
1.
Close the gas cock or manual gas shutoff (see
Figure 11) and shut off the main disconnect switch.
2. Isolate the 9600 HWG unit from the system by
closing the shutoff valves. If recirc. lines are piped,
isolate the return system from water heater.
3. Remove the lower front panel from the water
heater and connect a hose to the drain fitting.
(Located under the cylindrical chamber). Relieve
pressure at drain.
4. Connect a hose to the drain (provided by
installer) on the cold (return) side piping to the
appliance.
5. Remove cover from thermostatic valve and
remove thermostat. Wrap tape around / over
cutaway sections in the cover and replace all
parts except thermostat. Reinstall valve cover
and tighten bolts.
6. Fill the water heater combustion coil with
deliming solution from the hose connected under
boiler coil assembly until it exits from upper
hose. A small pump should be used to do the
filling from a plastic container. The upper hose
should then be placed in this container and the
pump should run until the circulating solution is
no longer foamy.