23
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
The amount of calcium carbonate (lime) 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. This is the lime scale which forms in
pipes, heaters and on cooking utensils.
Lime accumulation not only reduces the life of the equipment but
also reduces efficiency of the heater and increases fuel
consumption.
The usage of water softening equipment greatly reduces the
hardness of the water. However, this equipment does not
always remove all of the hardness (lime). For this reason it is
recommended that a regular schedule for deliming be
maintained.
The depth of lime buildup should be measured periodically.
Heaters will have about 3" (7.6cm) of lime buildup when the level
of lime has reached the bottom of the cleanout opening or about
1" (2.5cm) of lime buildup if it has reached the drain valve opening.
A schedule for deliming should be set up, based on the amount
of time it would take for a 1" (2.5cm) buildup of lime.
Example 1:
Initial inspection shows 1/2" (1.3cm) of lime accumulation.
Therefore, the heater can be delimed once a year.
Example 2 :
Initial inspection shows 2" (5cm) of lime accumulation.
Therefore, the heater should be delimed every 3 months.
Sediment and lime scale removal may be accomplished through
the cleanout opening furnished on the heater, see Figure 24. The
heater must be drained, see DRAINING, before removing cleanout
cover on tank.
FIGURE 24.
MAINTENANCE SCHEDULE
Following are the instructions for performing some of the
recommended maintenance. Unit inspection and adjustment
should be performed by a competent technician.
NOTE: UN•LIME is not available in Canada. Please call Customer
Service at 1-800-265-8520 for approved alternatives.
FLUSHING
1. Turn off the heater electrical disconnect switch.
2. Open the drain valve and allow water to flow until it runs clean.
3. Close the drain valve when finished flushing.
4. Turn on the heater electrical disconnect switch.
DRAINING
The heater must be drained if it is to be shut down and exposed
to freezing temperatures. Maintenance and service procedures
may also require draining the heater.
1. Turn off the heater electrical disconnect switch.
2. Close the cold water inlet valve to heater.
3. Open a nearby hot water faucet to vent the system.
4. Open the heater drain valve.
5. If the heater is being drained for an extended shutdown, it is
suggested the drain valve be left open during this period.
• Follow FILLING instructions when restoring hot water service.
COMPONENT OPERATION INTERVAL REQUIRED
Tank Sediment Monthly Flushing
Removal
Tank Lime Scale Semi UN-LIME®
Removal Annually Delimer
Powered Anode Inspect Semi
System Annually
Relief Valve Inspect Semi
Annually
SAE No. 20
Circulating Oiling Four Months non-detergent
Pump (1) motor oil
Clean Inlet
Blower Screen and As Required Soft Brush
Blower Wheel
Vent System Inspect Every 3 Joints should
Months be sealed
(1) If furnished with oiling provision.