Typical plumbing applications, Service and maintenance, Water temperature is too hot – John Wood Commercial Storage Tanks 80G - 120G User Manual
Page 4: Hot water odour, Discoloured water, Storage tank unit makes noise, Extended non use service, Cathodic protection: anode maintenance, Warning, Tank flushing
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TYPICAL PLUMBING APPLICATIONS
HOT
OUTLET
AQUASTAT
SHUT
OFF
VALVE
H
C
BOILER
TANKLESS
COIL
BRONZE
CIRCULATOR
COLD
INLET
HOT
OUTLET
HOT
OUTLET
HOT
OUTLET
HOT
OUTLET
HOT
OUTLET
HOT
OUTLET
AQUASTAT
AQUASTAT
AQUASTAT
AQUASTAT
AQUASTAT
SHUT OFF VALVE
SHUT
OFF
VALVE
BRONZE
CIRCULATOR
BRONZE
CIRCULATOR
BRONZE
CIRCULATOR
BRONZE
CIRCULATOR
COLD
INLET
COLD
INLET
COLD
INLET
COLD
INLET
CHECK
VALVE
CHECK
VALVE
CHECK
VALVE
CHECK
VALVE
CHECK VALVE
CHECK
VALVE
CHECK
VALVE
CHECK VALVE
CHECK
VALVE
RECIRCULATING
LOOP
RECIRCULATING
LOOP
BRONZE
CIRCULATOR
BRONZE
CIRCULATOR
SOURCE
SOURCE
SOURCE
SOURCE
SOURCE
SU
PP
LY
SU
PP
LY
SUPPLY
RETURN
RETURN
RETURN
SUPPLY
SUPPLY
SUPPLY
SUPPLY
RETURN
RETURN
RETURN
RETURN
IF USED CHECK VALVE
REQUIRE EXPANSION
TANK
IF USED CHECK VALVE
REQUIRE EXPANSION TANK
EXPANSION
TANK
(OPTIONAL)
RECOMMENDED
EXPANSION
TANK
(OPTIONAL)
RECOMMENDED
Water Temperature is Too Hot
-Check that the thermostat setting is not too high on your hot
water source unit.
-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 section of this manual.
-If the problem persists, contact your dealer, electric utility,
or gas supplier.
Hot Water Odour
Occasionally, and depending on your location, hot water may
develop a strong odour. This can be especially problematic
in regions where the water contains sulphur, which results in
hot water having a “rotten egg” type of smell.
If this occurs, drain the system completely, flush thoroughly,
and refill the unit. If the problem persists, the anode rod may
need to be changed from the magnesium type that is
installed, to one made of aluminum. In certain cases,
chlorination and flushing of the water system may be
required. Contact your 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 contaminates in
the water supply. This can be problematic in areas where the
water is obtained from surface or contaminated sources.
Organic particles can develop bacterial growth, causing
potential health hazards. Contact your water supplier for
proper filtration of water conditioning equipment. For
bacterial problems, contact your local health authority.
-A sudden appearance of rusty water can indicate that 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.
Storage Tank Unit Makes Noise
-Sediment, sand or scale can accumulate resulting in
“rumbling” or “hissing” noises. Water heaters need to be
flushed regularly to minimize buildup (See Tank Flushing).
Severe accumulations can cause premature failure of the
unit and will void the warranty.
Extended Non Use Service
-Hydrogen gas can be produced by water heaters in service,
especially ones that have been 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 when opening faucets.
Cathodic Protection: Anode Maintenance
Your storage tank unit has been supplied with an anode
rod(s) 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 anywhere from one to ten
years. Many localities treat their water, which can have
significant effect on the life of the unit. Water conditioning
such as over softening can accelerate the rate at which the
anode rod is consumed. Rapid depletion 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. The anode must be replaced with a new
one if it is less than 3/8” in diameter, or if any bare core is
showing.
To Inspect or Change an Anode:
1. Close the supply inlet valve.
2. Open a hot water tap supplied by the heater.
3. Drain the storage tank unit enough to empty the water in
the piping system.
4. Lift and “pop” off the plastic covers that cover access to
the anodes. Cut any insulation or foam as required.
5. Using a 1-1/16” socket, remove the anode and inspect or
replace it as required.
6. Refill the unit with water.
WARNING:
OPERATING THE UNIT WITHOUT AN
ACTIVELY WORKING ANODE ROD WILL VOID THE
WARRANTY.
Tank Flushing
Periodically (monthly) drain approximately 2 gallons (8 liters)
of water from the tank through the drain valve. This will
minimize sediment buildup on the tank bottom. All Storage
Tanks are supplied with a hand hole cleanout. All water must
be drained from the piping system and the unit prior to
opening the hand hole cleanout.
CAUTION:
WATER WILL BE HOT
Tank Clean-Out
A clean out opening is provided on all insulated storage tank
models for periodic cleaning of the tank. THE UNIT &
ASSOCIATED WATER LINES MUST BE DRAINED
COMPLETELY BEFORE OPENING THE CLEAN-OUT.
CAUTION:
TANK MAY BE HOT.
To clean the unit using the clean-out opening, proceed as
follows:
1. Remove the outer door ( casing door ).
SERVICE AND MAINTENANCE