Check Expansion Tank; Check Water Heater Relief Valve; Inspect Ignition & Flame Sense Electrodes; Check Ignition Ground Wiring - Lochinvar Shield SNR150-100 Installation & Service Manual

11
Maintenance

Check expansion tank

1. Expansion tanks provide space for water to move in and
out as the water expands due to temperature increase or
contracts as the water cools. Tanks must be approved for
potable water systems. See Section 5 - System Piping for
suggested best location of expansion tanks.

Check water heater relief valve

1. Inspect the relief valve and lift the lever to verify flow.
Before operating any relief valve, ensure that it is
piped with its discharge in a safe area to avoid severe
scald potential. Read Section 5 - System Piping before
proceeding further.
Safety relief valves should be re-inspected
WARNING
AT LEAST ONCE EVERY THREE
YEARS, by a licensed plumbing contractor
or authorized inspection agency, to
ensure that the product has not been
affected by corrosive water conditions
and to ensure that the valve and discharge
line have not been altered or tampered
with illegally. Certain naturally occurring
conditions may corrode the valve or its
components over time, rendering the
valve inoperative. Such conditions are
not detectable unless the valve and its
components are physically removed and
inspected. This inspection must only be
conducted by a plumbing contractor or
authorized inspection agency – not by
the owner. Failure to re-inspect the water
heater relief valve as directed could result
in unsafe pressure buildup, which can
result in severe personal injury, death, or
substantial property damage.
Following installation, the valve lever
WARNING
must be operated AT LEAST ONCE
A YEAR to ensure that waterways are
clear.
mineral deposits may adhere to the valve,
rendering it inoperative. When manually
operating the lever, water will discharge
and precautions must be taken to avoid
contact with hot water and to avoid water
damage. Before operating lever, check
to see that a discharge line is connected
to this valve directing the flow of hot
water from the valve to a proper place of
disposal. Otherwise severe personal injury
may result. If no water flows, valve is
inoperative. Shut down the water heater
until a new relief valve has been installed.
(continued)
Certain naturally occurring
Installation & Service Manual
TM
2. After following the warning directions, if the relief valve
weeps or will not seat properly, replace the relief valve.
Ensure that the reason for relief valve weeping is the valve
and not over-pressurization of the system due to expansion
tank waterlogging or undersizing.
Inspect ignition and flame sense
electrodes
1. Remove the ignition and flame sense electrodes from the
water heater heat exchanger access cover.
2. Remove any deposits accumulated on the ignition/flame
sense electrode using sandpaper. If the electrodes cannot be
cleaned satisfactorily, replace with new ones.
3. Replace ignition/flame sense electrode, making sure gasket
is in good condition and correctly positioned.

Check ignition ground wiring

1. Inspect water heater ground wire from the heat exchanger
access cover to ground terminal strip.
2. Verify all wiring is in good condition and securely attached.
3. Check ground continuity of wiring using continuity meter.
4. Replace ground wires if ground continuity is not satisfactory.
Check all water heater wiring
1. Inspect all water heater wiring, making sure wires are in
good condition and securely attached.

Check control settings

1. Set the control module display to Parameter Mode and
check all settings. Adjust settings if necessary. See Section
1 of this manual for adjustment procedures.
2. Check settings of external limit controls (if any) and adjust
if necessary.
Perform start-up and checks
1. Start water heater and perform checks and tests specified in
Section 9 - Start-up.
2. Verify cold fill pressure is correct and that operating
pressure does not go too high.
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