John Wood Polaris Commercial High-Efficiency - Manual (Page 24)

24
OPERATIONAL CONDITIONS
MAINTENANCE
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. 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 “Drain-
ing and Flushing”.
Safety Shut-Off (Pressure Switch)
This water heater is equipped with a pressure switch that
protects the unit by shutting it down in the event that:
•
A blockage occurs in the combustion air inlet, the
flue gas exhaust outlet, or both the inlet and outlet.
• The condensate line freezes and the condensate
“backs up” and fills the exhaust outlet.
• The blower fails to operate, or operates improperly.
• The unit begins to operate at an abnormally low
input level.
Energy Cut-Off (ECO)
A high temperature limit switch, or ECO, is used to shut
down the water heater if the water temperature exceeds
203°F (95°C). The ECO will automatically reset when
the temperature cools sufficiently. If the ECO shuts down
the heater repetitively, contact a qualified professional for
service.
Draining and Flushing
It is recommended that the tank be drained and flushed
every 6 months to remove sediment which may buildup
during operation. The water heater should be drained if
being shut down during freezing temperatures.
To drain the tank, perform the following steps:
1.
Turn off the gas supply at the Manual Gas Shut-off
Valve. Turn off the electrical supply to the water
heater.
2.
Open a nearby hot water faucet and run until the
water is no longer hot.
3. Close the cold water inlet valve.
4.
Open the left-hand access panel at the bottom of the
heater (see figure 23). Connect a hose to the drain
valve and terminate it to an adequate drain or external
to the building.
5. Open the water heater drain valve and allow all of the
water to drain from the tank.
6. Flush tank to remove sediment.
7. Close the drain valve, replace access door, refill
the tank, and restart the heater as directed under
“Operating Your Water Heater”.
IMPORTANT: Condensation may occur when refilling the
tank and should not be confused with a tank leak.
Temperature and Pressure
Relief Valve
Manually operate the
temperature and pressure
relief valve at least once
a year to make sure it is
working properly. To prevent
water damage, the valve
must be properly connected
to a discharge line which
terminates at an adequate
drain. Standing clear of the
outlet (discharged water may
be hot), slowly lift and release
the lever handle on the
temperature and pressure relief valve to allow the valve to
operate freely and return to its closed position (see figure
24). If the valve fails to completely reset and continues to
release water, immediately shut off the manual gas valve
and the cold water inlet valve, and call a qualified service
technician.
Drain Valve
Behind
Access Door
Figure 23: Drain Valve Access
Figure 24 Figure 24