John Wood Commercial - AJWSC - Manual (Page 20)

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Burner Flames
Inspect the burner flames through the viewport and com-
pare them to the drawings in Figure 15. A properly operat-
ing burner should produce a soft blue flame and be about
50mm (2 in.) to 64mm (2 -1/2 in.) in height. Blue tips with
yellow inner cones are satisfactory. The tips of the flame
may have a slight yellow tint. The flame should not be all
yellow or have a sharp blue-orange colour. Contaminated
air may cause an orange coloured flame. Contact a qualified
service technician if the flame is not satisfactory.
Stacking
Stacking occurs when a series of short draws of hot water
are taken from the water heater tank. This causes increased
cycling of the burner and can result in increased water tem-
peratures at the hot water outlet. A tempering valve should
be installed in the hot water supply line to reduce the risk of
scald injury.
Emergency Shut Down
Important: If overheating occurs or the gas supply fails to
shut off, close the manual gas supply shut-off valve and turn
the gas valve knob to the “OFF” position. Turn off the elec-
trical supply to the unit and close the cold water supply
valve. Do not operate the water heater again until it has
been thoroughly checked by a qualified service technician.
Operational Conditions
Condensation
Moisture from the products of combustion condenses on the
tank surface and the outside jacket of the water heater and
forms drops of water which may fall onto the burner or other
hot surfaces. This will produce a “sizzling” or “frying” noise.
This condensation is normal and should not be con-
fused with a leaking tank. Condensation may increase or
decrease at different times of the year.
High efficient energy saver water heaters will produce larg-
er amounts of condensation on initial start up or when a
large amount of hot water is being used. Do not confuse
this with a “tank leak”. Once the water reaches a temper-
ature of 49°C (120°F) and the tank warms up (usually 1-2
hours), the condensation will stop.
Important: It is always recommended that a suitable drain
pan be installed under the water heater to protect the area
from water damage resulting from normal condensation pro-
duction, a leaking tank or piping connections. Under no cir-
cumstances is the manufacturer to be held responsible for
any water damage in connection with this water heater.
Water Heater Sounds
During the normal operation of the water heater sounds or
noises may be heard. These noises are common and may
result from the following:
1. Normal expansion and contraction of metal parts during
periods of heat-up and cool-down.
2. Condensation causes sizzling and popping within the
burner area and should be considered normal.
3. Sediment buildup in the tank bottom will create varying
amounts of noise and may cause premature tank fail-
ure. Drain and flush the tank as directed under
“Draining and Flushing”.
Smoke/Odour
The water heater may give off a small amount of smoke and
odour during the initial start-up of the unit. This is due to the
burning off of oil from metal parts of a new unit and will dis-
appear after a few minutes of operation.
High Humidity or Dripping Water
Over time, dripping water or high ambient humidity can cre-
ate unwanted electrical paths on the circuit board, causing
the integrated control to fail. Never install an appliance
where water can drip on the controls. In addition, high ambi-
ent humidity can cause the gas valve to corrode and finally
fail. Where the appliance may be installed in a humid
2 - 2 1/2”
Figure 15 Pilot/Burner Flame
50 - 64mm (2 - 2 1/2 in.)
VI) INTEGRATED CONTROL
WARNING
Fire or Explosion Hazard
Can cause severe injury, death or
property damage.
1. The integrated control can malfunction if
it gets wet, leading to accumulation of
explosive gas.
. Never install where water can flood, drip
or condense on the integrated control.
. Never try to use an integrated control
that has been wet - replace it.
2. Liquefied petroleum (LP) gas is heavier
than air and will not vent upward natural-
ly.
. Do not light pilot or operate electric
switches, lights, or appliances until you
are sure the appliance area is free of
gas.
3. If a new gas valve is to be installed, turn
off gas supply before starting installation.
Conduct Gas Leak Test according to gas
valve manufacturer’s instructions after
the gas vavle is installed.
4. If the integrated control must be mounted
near moisture or water, provide suitable
waterproof enclosure.