John Wood Superflue Power Vent (75 Gallon) - Manual (Page 29)

Water is Too Hot
• Check that thermostat setting is not too high.
• Water heaters used for dishwashers, space heating or
laundry facilities generally require higher temperatures
than domestic use. Install anti-scald tempering valves
as instructed in the safety warnings.
• See also “Temperature Regulation”.
• If the problem persists, contact your dealer or gas sup-
plier.
Hot Water Odour
On occasion, and depending on your location, hot water
may develop a strong odour. This can be especially prob-
lematic in regions where the water contains some sulphur,
which results in hot water having a “rotten egg” smell.
If this occurs, drain the system completely, flush thoroughly
and refill. If the problem persists, the anode rod may need
to be changed from magnesium to one made of aluminum.
In certain cases chlorination and flushing of the water heater
may be required. Contact you dealer or water supplier.
Discoloured Water
• Water rich in iron or other minerals can produce red or
brown staining. Heating water generally worsens this
situation.
• Black water can be an indication of organic contami-
nates in the water supply. This can be problematic in
areas where the water is obtained from surface or con-
taminated sources. Organic particles can develop bac-
terial growth, causing potential health hazards. Contact
your water supplier for proper filtration or water condi-
tioning equipment. For bacterial problems contact your
local health authority. See also “Hot Water Odour”
• A sudden appearance of rusty water can indicate the
anode rod has been depleted. The remaining steel core
wire may be corroding, releasing iron particles into the
water. Inspect and replace as necessary.
Water Heater Makes Noise
• During start up or under heavy use, condensation can
drip on the burner causing a sizzling noise as the water
is evaporated. This is normal and will stop once tem-
peratures rise.
• Sediment, sand or scale can accumulate resulting in
“rumbling” noises. Water heaters need to be flushed
regularly to minimize buildup. Severe accumulations
can cause premature failure of the water heater and will
void the warranty.
• Vent piping can vibrate if it is not supported properly.
Ensure hangers and vibration isolators are properly
installed.
Extended Non Use Service
Hydrogen gas can be produced by water heaters in service
but on standby for long periods of time (generally two weeks
or more). See safety warnings in the front of the manual.
Hydrogen gas is extremely flammable. Use caution in open-
ing faucets.
Condensation
Water vapor in the flue gases can condense on the cooler
surfaces of the water heater, especially during the start of a
cold tank, during heavy use, or if the water heater is under-
sized. Condensation can also be produced in the vent pip-
ing if the vent piping becomes chilled (e.g. going through
unheated areas) or if the dilution air is very cold.
Condensation may give the false impression that there is a
tank leak as significant amounts can drip out of the bottom
of the water heater. Once the water heater is operating at
normal temperatures tank condensation should disappear.
See “Venting” section for dealing with condensation in the
vent piping.
Anode Maintenance
Your water heater has been supplied with an anode rod that
protects the tank from corrosion. As the rod works, it slowly
dissolves over time and must be replaced when it becomes
totally consumed. Depending on water conditions, an anode
can last several years. Most localities treat their water,
which can have significant effect on the life of your heater.
Water conditioning such as over softening can accelerate
the rate at which the anode rod is consumed. Rapid deple-
tion can leave a heater unprotected causing a premature
failure. As with any water heater, it is good practice to check
the anode annually to see if it needs replacing (Figure 1,
Item No. 15).
To inspect or change an anode:
• turn off the water heater
• close the cold inlet supply valve
• open a hot water tap supplied by the heater.
• drain the water heater enough to empty the piping sys-
tem.
• using a 1 1/16” socket, remove anode and inspect or
replace as required.
• refill system with water and restore water heater to
operation.
Warning: Operating a water heater without an actively
working anode rod will void the warranty.
Tank Flushing
Periodically (monthly) drain approximately 8 liters (2 gal-
lons) from the tank through the drain valve. This will mini-
mize sediment buildup on the tank bottom.
Caution: WATER WILL BE HOT.
If scale removal is being considered, contact your dealer for
proper procedures. DO NOT USE HYDROCHLORIC ACID
(HCL) based cleaners. Thoroughly flush after any chemical
cleaning.
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