John Wood Electric Water Heaters - NEW - Manual (Page 15)

15
TEMPERATURE-PRESSURE RELIEF VALVE OPERATION
The temperature-pressure relief valve must be manually operated
at least once a year.
When checking the temperature-pressure relief valve operation, make sure
that (1) no one is in front of or around the outlet of the temperature-pressure
relief valve discharge line, and (2) that the water discharge will not cause
any property damage, as the water may be extremely hot, see Figure 9.
FIGURE 9.
If after manually operating the valve, it fails to completely reset and
continues to release water, immediately close the cold water inlet
to the water heater, follow the draining instructions, and replace the
temperature-pressure relief valve with a new one.
If the temperature-pressure relief valve on the appliance weeps
or discharges periodically, this may be due to thermal expansion.
You may have a check valve installed in the water line or a water
meter with a check valve. Consult your local water supplier or
service agency for further information. Do not plug or remove the
temperature-pressure relief valve.
DRAINING AND FLUSHING
It is recommended that the tank be drained and fl ushed every 6
months to remove sediment which may build up during operation. The
water heater should be drained if being shut down during freezing
temperatures. To drain the tank, perform the following steps:
1. Turn off power to the water heater.
2. Open a nearby hot water faucet until the water is no longer hot.
3. Close the cold water inlet valve.
4. Connect a hose to the drain valve and terminate it to an adequate
drain or external to the building.
ANODE ROD INSPECTION AND REPLACEMENT
Each water heater contains at least one anode rod, which will slowly
deplete (due to electrolysis), prolonging the life of the water heater
by protecting the glass-lined tank from corrosion. Adverse water
quality, hotter water temperatures, high hot water usage, and water
softening methods can increase the rate of anode rod depletion.
Once the anode rod is depleted, the tank will start to corrode,
eventually developing a leak.
Certain water conditions will cause a reaction between the anode
rod and the water. The most common complaint associated with
the anode rod is a “rotten egg smell” produced from the presence
of hydrogen sulfi de gas dissolved in the water. IMPORTANT: Do not
remove this rod permanently as it will void any warranties. A special
anode rod may be available if water odor or discoloration occurs.
NOTE: This rod may reduce but not eliminate water odor problems.
The water supply system may require special fi ltration equipment
from a water conditioning company to successfully eliminate all
water odor problems.
Artifi cially softened water is exceedingly corrosive because the
process substitutes sodium ions for magnesium and calcium ions.
The use of a water softener may decrease the life of the water
heater tank.
The anode rod should be removed from the water heater tank
every 3 years for inspection. NOTE: Artifi cially softened water
requires the anode rod to be inspected annually.
The following are typical (but not all) signs of a depleted anode rod:
• The majority of the rod’s diameter is less than 3/8 inch (9.5 mm).
• Signifi cant sections of the support wire (approx. 1/3 or more
of the anode rod’s length) are visible. If the anode rod shows
signs of either or both, it should be replaced. NOTE: Whether
re-installing or replacing the anode rod, check for any leaks and
immediately correct if found.
FIGURE 8A.
In replacing the anode:
1. Turn off power to the water heater.
2. Shut off the water supply and open a nearby hot water faucet to
depressurize the water tank.
3. Drain approximately 5 gallons of water from tank. (Refer to “Draining
and Flushing” for proper procedures). Close drain valve.
4. Remove old anode rod.
5. Use Tefl on
® tape or approved pipe sealant on threads and install
new anode rod.
6. Turn on water supply and open a nearby hot water faucet to purge
air from water system. Check for any leaks and immediately
correct any if found.
7. Restart the water heater as directed in this manual. See the
Repair Parts Illustration for anode rod location.
PERIODIC MAINTENANCE