20
6.Check main burner operation by cycling on and off the
thermostat dial several times. Wait 1 minute between cycles for
regulators and sequencing to reset.
7. When all adjustments are satisfactory:
•
Fill in part no. 170037 “Start-up” form.
•
Adjust thermostat temperature dial to deliver desired
water temperature at point of use.
•
For subsequent normal starting and shutoff procedure,
see OPERATIONAL PROCEDURE.
MAINTENANCE
MAINTENANCE SCHEDULE
Water heater maintenance includes periodic tank flushing and
cleaning, and removal of lime scale. The power burner should
be inspected and adjusted to maintain proper combustion. Refer
to table 7. A periodic inspection of the venting system and
barometric damper should be made. Where used, the water
heating system circulating pump should be oiled.
Following are the instructions for performing some of the
recommended maintenance. Power burner inspection and
adjustment should be performed by a competent technician.
TABLE 7
RECOMMENDED MAINTENANCE SCHEDULE
FOR THE ***81-140 THRU ***81-370 HEATER
COMPONENTS
OPERATION
INTERNAL
REQUIRED
Flushing
Monthly
Sediments
Tank
Removal
Semi-Annually
Lime Scale
Un•Lime
Removal
As Required
Delimer
Relief Valve
Inspect
Semi-Annually
Circulating Pump
SAE No. 20
and Power
Oiling
Quarterly
Non-Detergent
Burner Motor(1)
Motor Oil
Power Burner
Combustion Test
and Ignition
Inspection
Kit and Test
Device (2)
and Adjustment Semi-Annually
Specifications
Main Burner
Inspect
Semi-Annually
Vent System and
Barometric
Draft
Damper
Inspect
Semi-Annually
Gauge
Anode(s)
Inspect
Annually
FLUSHING
1. Turn off the heater electrical disconnect switch.
•
For convenience, the switch on the outside of the control
compartment can be used.
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.
Reverse these instructions when restoring hot water service.
SEDIMENT REMOVAL
Waterborne impurities consist of fine 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 build-up should be measured periodically.
Heaters will have about 3" of lime build-up when the level of lime
has reached the bottom of the cleanout opening or about 1" of
lime build-up 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" build-up of lime.
Example 1:Initial inspection, six months after installation, shows
1/2" of lime accumulation. Therefore, the heater can be
delimed once a year.
Example 2:Initial inspection, six months after installation, shows
2" 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 DRAIN VALVE
AND ACCESS PANELS. The heater must be drained, see
DRAINING, before removing cleanout cover on tank.
To dissolve and remove the more stubborn mineral deposits,
UN•LIME
®
Professional Delimer should be used.
UN•LIME Delimer is an easy-to-handle patented food grade acid
formulated specifically for lime scale removal from all types of
water using equipment. Available in 1 gallon (part no. 4763) and
5 gallon (part no. 4813) sizes. Hydrochloric base acids are not
recommended for use on glass-lined tanks.
Form No. 4800, entitled “Why, When and How”, describes tank
cleaning methods and materials. UN•LIME and the booklet may
be obtained through your dealer or distributor.
