John Wood Envirosense Power Direct Vent (prior to May 2010) - Manual (Page 37)

37
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 sulfide gas dissolved in the water. IMPORTANT: Do
not remove this rod permanently as it will void any warranties.
The parts list includes a special anode rod that can be ordered if
water odor or discoloration occurs. NOTE: This rod may reduce
but not eliminate water odor problems. The water supply system
may require special filtration equipment from a water conditioning
company to successfully eliminate all water odor problems.
Artificially 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: artificially 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 rods diameter is less than 3/8”.
* Significant sections of the support wire (approx. 1/3 or more of
the anode rod’s length) are visible.
If the anode rod show 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.
In replacing the anode:
1. Turn off gas supply 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 Teflon® tape or approved pipe sealant on threads and install
new anode rod.
6. Turn on water supply and open nearby hot water faucet to purge
air from water system. Check for any leaks and immediately
correct any if found.
Restart the water heater as directed under “Operating Your Water
Heater.” See the Repair Parts Illustration for anode rod location.
fIGure a. anode rod depletIon
teMperature-pressure
relIef valve operatIon
fIGure 35.
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 28.
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 a qualified
service agency for further information. Do not plug the temperature-
pressure relief valve.
draInInG and flushInG
It is recommended that the tank be drained and flushed 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. Set the power switch to the “OFF” position.
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 to an adequate
drain or external to the building.
5. OPEN the water heater drain valve and allow all of the water
to drain from the tank. Flush the tank with water as needed to
remove sediment.
6. CLOSE the drain valve, refill the tank, and restart the heater as
directed in this manual.
If the water heater is going to be shut down for an extended period,
the drain valve should be left open.
IMPORTANT: Condensation may occur when refilling the tank and
should not be confused with a tank leak.