EXTERNAL DAMAGE
Do not operate the water heater until it has been fully checked out by a qualified technician, if the water heater:
•Has been exposed to fire or damage.
•Displays evidence of sooting.
•Produces steam or unusually hot water.
If the water heater has been flooded it must be replaced.
START UP CONDITIONS
NEVER OPERATE THE HEATER WITHOUT FIRST BEING CERTAIN IT IS FILLED WITH WATER AND A TEMPERATURE AND PRESSURE RELIEF VALVE IS INSTALLED IN THE RE- LIEF VALVE OPENING OF THE HEATER. DO NOT ATTEMPT TO OPERATE HEATER WITH COLD WATER INLET VALVE CLOSED.
CONDENSATE
Whenever the water heater is filled with cold water, some con- densate will form while the burner is on. A water heater may appear to be leaking when in fact the water is condensate. This usually happens when:
a.A new water heater is filled with cold water for the first time.
b.Burning gas produces water vapor in water heaters, par- ticularly high efficiency models where flue temperatures are lower.
c.Large amounts of hot water are used in a short time and the refill water in the tank is very cold.
Moisture from the products of combustion condense on the cooler tank surfaces and form drops of water which may fall onto the burner or other hot surfaces to produce a “sizzling” or “frying” noise.
Because of the suddenness and amount of water, condensate water may be diagnosed as a “tank leak”. After the water in the tank warms up (about 1-2 hours), the condition should disap- pear.
Do not assume the water heater is leaking until there has been enough time for the water in the tank to warm up.
An undersized water heater will cause more condensation. The water heater must be sized properly to meet the family’s de- mands for hot water including dishwashers, washing machines and shower heads.
Excessive condensate may be noticed during the winter and early spring months when incoming water temperatures are at their lowest.
Good venting is essential for a gas fired water heater to operate properly as well as to carry away products of combustion and water vapor.
SMOKE/ODOR
It is not uncommon to experience a small amount of smoke and odor during the initial start-up. This is due to burning off of oil from metal parts, and will disappear in a short while.
THERMAL EXPANSION
Water supply systems may, because of such events as high line pressure, frequent cut-offs, the effects of water hammer among others, have installed devices such as pressure reducing valves, check valves, back flow preventers, etc. to control these types of problems. When these devices are not equipped with an internal by-pass, and no other measures are taken, the devices cause the water system to be closed. As water is heated, it expands (thermal expansion) and closed systems do not allow for the expansion of heated water.
The water within the water tank expands as it is heated and in- creases the pressure of the water system. If the relieving point of the water heater’s temperature-pressure relief valve is reached, the valve will release the excess pressure. The temperature- pressure relief valve is not intended for the constant relief of thermal expansion. This is an unacceptable condition and must be corrected. It is recommended that any devices installed which could create a closed system have a by-pass and/or the system have an expansion tank or device to relieve the pressure built by thermal expansion in the water system. Expansion tanks are available for ordering through a local plumbing contractor. Contact the local water heater supplier or service agency for as- sistance in controlling these situations.
STRANGE SOUNDS
Possible noises due to expansion and contraction of some metal parts during periods of heat-up and cool-down do not necessarily represent harmful or dangerous conditions.
Condensation causes sizzling and popping within the burner area during heating and cooling periods and should be consid- ered normal. See “Condensate” in this section.
OPERATIONAL CONDITIONS
SMELLY WATER
In each water heater there is installed at least one anode rod (see parts section) for corrosion protection of the tank. Certain water conditions will cause a reaction between this rod and the water. The most common complaint associated with the anode rod is one of a “rotten egg smell” in the hot water. The smell is a result of four factors which must all be present for the odor to develop:
a.A concentration of sulfate in the supply water.
b.Little or no dissolved oxygen in the water.
c.A sulfate reducing bacteria which has accumulated within the water heater (this harmless bacteria is nontoxic to humans).
d.An excess of active hydrogen in the tank. This is caused by the corrosion protective action of the anode.
Smelly water may be eliminated or reduced in some water heater models by replacing the anode(s) with one of less active mate- rial, and then chlorinating the water heater tank and all water
