45
6.
Open the water heater drain valve to flush the storage tank.
7.
Flush the water heater storage tank to remove sediment and
allow the water to flow until it runs clean.
8.
Close the water heater drain valve when flushing is completed.
9.
Remove the drain hose.
10.
Fill the water heater. See
Filling the Water Heater
(page 42).
11.
Reconnect the water heater to the electrical supply to place the
water heater back in operation.
12.
Allow the water heater to complete several heating cycles to
ensure it is operating properly.
SEDIMENT REMOVAL
Waterborne impurities consist of the particles of soil and sand which
settle out and form a layer of sediment on the bottom of the tank.
For convenience, sediment removal and lime scale removal should
be performed at the same time.
LIME SCALE REMOVAL
When water is heated dissolved minerals in the water such as
calcium and magnesium carbonate (lime scale) become less
soluble. As the water temperature rises these minerals will
precipitate or “fall out” of solution.
The amount of lime scale released from water is in direct proportion
to water temperature and usage. The higher the water temperature
or water usage, the more lime deposits are dropped out of the water.
Water hardness also affects lime scale accumulation. With the
temperature and usage being the same, hard water will release
more lime scale than softer water.
Lime scale reduces heating efficiency as it accumulates inside a
water heater. Heating transfer surfaces become coated with lime
scale deposits which increases fuel costs to operate the water
heater. Lime scale deposits can also cause rumbling and pounding
noises as air molecules trapped in the lime scale escape when
heated. Lime scale accumulation also reduces the life span of
water heaters. For these reasons a regular schedule for deliming
should be set up.
The depth of lime accumulation in the bottom of the water heater
should be measured periodically. Inspect by removing the cleanout
cover once every 6 months at first. Deliming maintenance should
then be performed based on the time it takes for 1 inch (2.5 cm) of
lime to accumulate in the bottom of the water heater.
CHEMICAL LIME SCALE REMOVAL
To dissolve and remove more stubborn lime scale deposits, UN-
LIME
®
Professional Delimer should be used.
UN-LIME
®
Professional Delimer is an easy to handle patented
food grade acid formulated specifically for lime scale removal from
all types of water using equipment. Hydrochloric base acids must
not be used to delime the water heaters covered in this manual.
Follow the instructions on the UN-LIME
®
to delime the water heater.
Note:
Contact Technical Support for assistance in ordering the
UN-LIME
®
Professional Delimer.
BURNER OPERATION AND INSPECTION
At least once a year a visual inspection should be made of the
main burner and the hot surface igniter assembly for proper flame
characteristics and ignition sequences. This can be done by
removing the plastic cover. See
Figure 2
(page 8).
The main burner should provide complete combustion of gas, ignite
rapidly, give reasonably quiet operation, and cause no excessive
flame lifting from the burner ports. If the proper flame characteristics
are not evident, make sure that the flow of combustion and
ventilation air is not blocked. Inspection of exhaust/air intake
termination is needed to ensure there is no blockage there.
You should also check for sooting. Soot is not normal and will
impair proper combustion. A visual inspection of the main burner
and hot surface igniter should also be done at least once a year.
See
Figure 2
(page 8).
Soot build-up indicates a problem that requires correction before
further use. Turn “OFF” gas to water heater by unplugging the
power cord and leave off until repairs are made. Failure to correct
the cause of the sooting can result in a fire causing death, serious
injury, or property damage.
Figure 43. Burner-Blower Assembly
COMBUSTION CHAMBER AND BURNER CLEANING
In the event your burner or burner air openings require
cleaning, Call your service agency to remove and clean the
burner and correct the problem that required the burner to
be cleaned.
