John Wood FlowTHRU Storage Tanks - Manual (Page 6)

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Temperature Adjustment
Thermostats are factory set at 140°F (60°C). The thermo-
stat operates automatically. It can be adjusted to provide a
higher or lower water temperature.
If water temperature adjustment is required:
1. Turn the electrical supply "OFF".
2. Remove the access door and insulation pad.
3. Check with a voltage tester at terminal 1 and 3 of the limit
control that power is indeed "OFF".
4. Adjust the thermostat to the water temperature desired.
5. Ensure insulation pad is in the door cavity. Replace
access door(s).
6. Turn the electrical supply "ON".
Initial Temperature Adjustment
1. For the temperature controlled IWH, ensure the tem-
perature set point is 11°C (20°F) higher than the storage
tank set point.
2. If at the end of the recovery cycle, the IWH is OFF but
the circulator pump does not turn OFF automatically,
reduce the storage tank thermostat set point until the
pump shuts off. Check that pump is off.
Temperature Limit Control
For safety, a non-adjustable high limit temperature switch
will shut off the power when excessive water temperatures
are reached. This switch must be re-set manually.
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 connect-
ed to a discharge line that terminates at an adequate drain.
Standing clear of the outlet (discharged water may be
hot), slowly lift and release the lever handle on the temper-
ature and pressure relief valve (see Figure 5) to allow the
valve to operate freely and return to its closed position. If the
valve fails to completely reset and continues to release
water, immediately turn "OFF" the electrical supply to the
tank, close the cold water supply valve and call a qualified
service technician.
Draining and Flushing
It is recommended that the storage tank be drained and
flushed every 6 months to remove sediment that may build
up during operation. The storage tank should also be
drained if being shut down for extended periods of time. To
drain the tank, perform the following steps:
Figure 5 T&P Relief Valve Test
TEMPERATURE AND
PRESSURE RELIEF VALVE
MANUAL RELIEF VALVE
DISCHARGE LINE TO DRAIN
CAUTION
The out-flowing water is hot. Avoid splashing the water on
yourself or on the surroundings where it may cause dam-
age.
CAUTION
The water being drained can be extremely hot! The
drain hose should be rated for at least 93°C (200°F). If the
drain hose does not have this rating, open the cold water
supply valve and a nearby hot water faucet served by the
system until the water flow is no longer hot. Close the cold
water supply valve and resume.
V) MAINTENANCE
WARNING:
Risk of scalding
There is a hot water scald potential if the thermostat is set
too high.
Adjusting the thermostat past the 49°C (120°F) bar on the
temperature dial will increase the risk of scald injury. Hot
water can cause severe burns in:
1 1/2 seconds at. . . . . . . . . . . . . . 66°C (150°F)
3 seconds at . . . . . . . . . . . . . . . . . 60°C (140°F)
20 seconds at . . . . . . . . . . . . . . . . 54°C (130°F)
DANGER
Water temperature over 52°C (125°F) can cause
severe burns instantly or death from scalds.
Children, disabled and elderly are at highest risk of
being scalded.
See instruction manual before setting temperature
at the storage tank.
Feel water before bathing or showering.
Temperature limiting valves are available, see man-
ual.