John Wood SERIES 100 - Manual (Page 23)

23
FIGURE 16.
To dissolve and remove the more stubborn mineral 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. Available in 1 gallon (3.8L) (part no. 4763) and 5 gallon
(19L) (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
the tech. center.
The cleanout opening is shown in Figure 16. To clean heater through cleanout
opening, proceed as follow:
1. Turn off the water heater electrical disconnect switch and open a nearby
hot water faucet until the water runs cool, draining the water heater
completely.
2. Remove outer cover plate from lower side of heater jacket.
3. Remove cover from cleanout opening.
4. Remove lime, scale or sediment using care not to damage the
glass-lining.
5. Inspect cleanout plate gasket: If new gasket is required, replace with
kit # 9004099215.
6. Install cleanout plate. Be sure to draw plate up tight by tightening screws
securely.
7. Close drain valve, open water inlet line and turn on the water heater
electrical disconnect switch.
8. Check for water leakage.
9. Replace outer jacket cover plate.
POWERED ANODE SYSTEM
The (A)JWSH heaters are factory equipped with a powered anode system.
The anodes are of a permanent design and do not need replacing unless
damaged.
FLUSHING
1. Turn off the heater electrical disconnect switch.
2. Open a hot water faucet until the water runs cool and then close the hot
water faucet.
3. Open the drain valve and allow water to flow until it runs clean.
4. Close the drain valve when finished flushing.
5. 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. Open a nearby hot water faucet until the water runs cool.
3. Close the cold water inlet valve to heater.
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.
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 25. The heater must be drained,
see DRAINING, before removing cleanout cover on tank.