John Wood JW375T75N-AV, Instruction Manual

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(generally two weeks or more). Hydrogen gas is extremely
flammable and explosive. To prevent the possibility of injury
under these conditions, we recommend the hot water faucet,
located farthest away, be opened for several minutes before
any electrical appliances which are connected to the hot water
system are used (such as a dishwasher or washing machine). If
hydrogen gas is present, there will probably be an unusual sound
similar to air escaping through the pipe as the hot water faucet
is opened. There must be no smoking or open flame near the
faucet at the time it is open.
HIGH WATER TEMPERATURE SHUT OFF SYSTEM
This water heater is equipped with an automatic gas Shut-off
system. This system works when high water temperatures are
present. The high temperature Shut-off is built into the gas control
valve. It is non-resettable. If the high temperature Shut-off
activates, the gas control valve must be replaced. Contact your
gas supplier or service agency. Turn “OFF” the entire gas supply
to the water heater.
“AIR” IN HOT WATER FAUCETS
HYDROGEN GAS: Hydrogen gas can be produced in a hot
water system that has not been used for a long period of time
PERIODIC MAINTENANCE
VENTING SYSTEM INSPECTION
At least once a year a visual inspection should be made of the venting
system. You should look for:
1. Obstructions which could cause improper venting. The
combustion and ventilation air flow must not be obstructed.
2. Damage or deterioration which could cause improper venting
or leakage of combustion products.
3. Rusted flakes around top of water heater.
Be sure the vent piping is properly connected to prevent escape
of dangerous flue gases which could cause deadly asphyxiation.
Obstructions and deteriorated vent systems may present serious
health risk or asphyxiation.
Chemical vapor corrosion of the flue and vent system may occur
if air for combustion contains certain chemical vapors. Spray can
propellants, cleaning solvents, refrigerator and air conditioner
refrigerants, swimming pool chemicals, calcium and sodium chloride,
waxes, bleach and process chemicals are typical compounds which
are potentially corrosive.
If after inspection of vent system you found sooting or deterioration,
something is wrong. Call the local gas utility to correct problem and
clean or replace the flue and venting before resuming operation of
water heater.
BURNER INSPECTION
Flood damage to a water heater may not be readily visible or
immediately detectable. However, over a period of time a flooded
water heater will create dangerous conditions which can cause
DEATH, SERIOUS BODILY INJURY, OR PROPERTY DAMAGE.
Contact a qualified installer or service agency to replace a flooded
water heater. Do not attempt to repair the unit! It must be replaced!
At least once a year a visual inspection should be made of the main
burner and pilot burner, see Figure 19.
You should check for sooting. Soot is not normal and will impair
proper combustion.
Soot build-up indicates a problem that requires correction before
further use. Turn “OFF” gas to water heater and leave off until repairs
are made, because failure to correct the cause of the sooting can
result in a fire causing death, serious injury, or property damage.
NATURAL
PROPANE
FIGURE 19.
BURNER CLEANING
If inspection of the burner shows that cleaning is required, turn
the gas control knob clockwise ( ) to the “OFF” position,
depressing slightly.
NOTE: The knob cannot be turned from “PILOT” to “OFF”
unless knob is depressed slightly. DO NOT FORCE.
Loose deposits on or around the burner can be removed by carefully
using the hose of a vacuum cleaner inserted through the access door
of the water heater. If the burner needs to be removed for additional
cleaning, call a service agency to remove and clean the burner and
correct the problem that required the burner to be cleaned.