John Wood Commercial - ANED - Manual (Page 18)

Page 17
CATHODIC PROTECTION
Depending on the model, two or three magnesium anodes are
factory installed inside the tank to provide corrosion protection
and to extend tank life. Permanent removal of the anode(s) for
any purpose will void the warranty.
Read the warranty attached to this water heater for a full
explanation of the time period that parts and the heater are
warranted.
It is advisable to inspect the condition of the anode(s) at
certain intervals. A two year period may be a guide to begin
with. The life of the anode depends on many factors and can
differ greatly from one location to another.
To remove and anode, proceed as follows:
1. Turn the gas off at the inlet to the heater.
2. Turn water off at the cold water inlet valve.
3. Open a nearby HOT water tap.
4. Drain approximately two pails full of water from the
heater.
5. Remove the vent pipe and the draft hood. Remove the
hot and cold water connections.
6. Lift up the other casing top and the insulation under it.
7. Lift up the inner flue collector. NOTE: the flue collector
has a lip extending out on the circumference which can
be used for lifting.
8. With a 1-1/6” hex socket wrench, loosen the anode from
the fitting in the tank top.
NOTE: The anodes have been factory installed using a
power tool. It will be necessary for a second person to
restrain the heater. A few sharp blows on the handle of
the socket wrench will loosen the anode adapter.
If an impact wrench (power driven) is available, this is an
easy way to remove an anode.
9. Lift the anode up and inspect. There should be at least
3/8” to 1/2” of anode diameter left. The surface may be
rough, full of pits and crevices, but this is normal.
If there is less than approximately 3/8” diameter left, the
anode needs to be replaced.
10. Apply a good grade of pipe dope to the threads of the
anode adaptor and screw securely into the tank top.
11. Replace the flue collector. Make sure it seals all around
the circumference.
12. Replace the insulation and the casing top.
13. Re-connect hot and cold water lines.
14. Replace the draft hood and the vent pipe. NOTE: If the
vent pipe shows signs of corrosion or damage, replace it
with new material. See section on “Venting”
15. Open the cold water inlet valve and fill the tank.
16. Check for leaks.
17. To relight burners, follow “Lighting Instructions”
DISHWASHING MACHINE REQUIREMENTS
The heater may be operated to supply the 180 o F sanitizing
rinse water required by the public health code for dishwashing
machines. In such installations, the heater should be located
as close as possible to the dishwasher. If the distance between
the dishwasher and heater is greater than 5 ft. the pipes
should be insulated and recirculation of the 180
o F water should
be provided. The circulation flow rate should be enough to
provided 180
o F to the dishwasher, however, the rate should be
low to minimize turbulence inside the water heater.
Flow pressures to the dishwasher above 25 or below 15
pounds per square inch will not produce a proper rinse spray.
If flow pressure to the dishwasher is high a pressure reducing
valve should be used in the 180
o F line to deliver water at 20
pounds per square inch for the rinse cycle. If the flow is too low
a pressure booster should be installed.
MULTIPLE HEATERS IN SINGLE SYSTEM
When two or more water heaters are installed into a single sys-
tem, the following precautions must be taken to ensure that
each heater is able to deliver it’s full rated capacity of hot water
for maximum system efficiency.
1. Gas supply piping must be large enough (see table 1)
2. The combined flue pipe must be large enough. see
local codes.
3. The water connections must be properly manifolded.
WATER ODOR PROBLEMS
When the area water trace mineral content is high. The odor of
the water may be strong. Replacing the water by draining it
completely and flushing then refilling it may help. Chlorination
and replacement of magnesium anode with aluminum anode
may help if the problem persists.
CAUTION
Hydrogen gas can be produced in a hot water sys-
tem served by this heater that has not been used
for a long period of time (generally two weeks or
more). Hydrogen gas is extremely flammable. To
reduce the risk of injury under these conditions, it is
recommended that a hot water faucet be opened
for several minutes at the kitchen sink before using
any electrical appliances connected to the hot
water system. If hydrogen is present, there will
probably be an unusual sound such as air escaping
through the pipe as the water begins to flow. There
should be no smoking or open flame near the
faucet at the time it is opened.