John Wood Storage Booster Tanks - Manual (Page 4)

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tem, check valves must be installed to prevent the circulator
from pumping hot water into another tank and overheating
it.
8. The use of a pressure regulator is optional, but recom-
mended when the cold supply pressure is over 80 psi.
Reducing the inlet pressure to 45-60 psi will reduce
probability of relief valve discharge by thermal expan-
sion.
9. The water utility supply meter may contain a check
valve, back-flow preventer or water pressure reducing
valve. This will create a closed water system. During the
heating cycle, the water expands creating a pressure
build-up in the water system. A Temperature and
Pressure (T&P) Relief Valve must be installed (150 psi
maximum pressure). See preceding section. If the T&P
valve discharges periodically, this may be due to ther-
mal expansion in a closed system. To prevent this con-
dition and to reduce the possible build up of lime on the
Temperature and Pressure Relief Valve seat, either one
of the following installations is required;
i) Install a 125 psi pressure relief valve in the cold water
supply line. Make sure that the discharge of this valve is
protected from freezing and directed to an open drain.
ii) Install an expansion tank on the cold water supply
line.
10. A vacuum relief valve may be installed to provide vent-
ing of a closed system. Check local code requirements.
Electrical Wiring
Electrical wiring must be in accordance with local codes; or
in the absence of local codes with the National Electrical
code ANSI/NFPA 70 or The Canadian Electrical Code, as
applicable.
1. Supply 110/120 volt, 60Hz power, to the junction box
located at the top of the tank.
2. Connect the circulator pump in series with the thermo-
stat as shown in Figure 4.
3. A ground wire must be supplied from the ground con-
nection at the service panel to the ground screw at the
junction box.
4. The thermostat is rated for a maximum inductive current
of 7 FLA at 120 VAC. Do not exceed this rating for the
circuit.
5. Do not install or connect electrical heating elements to
this tank.
Filling
NOTE: When filling, avoid water leakage. Do not allow the
insulation of the tank to get wet as water can cause electri-
cal malfunction or reduce the effectiveness of the insulation.
1. To insure complete filling of the tank, allow air to exit by
opening a hot water faucet that is served by the tank
and is some distance away from the heater.
2. Ensure the storage tank drain valve is closed.
3. Open the cold water supply valve and fill the tank and
piping system with water. When an uninterrupted
stream of water, without apparent air bubbles, flows
from the open hot water faucet, the system is full.
4. Close the open hot water faucet. Check the system for
leaks, repair as necessary and retest.
5. Connect a hose to the drain valve and route to a suit-
able drain. Open the drain valve and let water run to
flush out any foreign matter that may have entered the
system. Once flushed, close the drain valve and dis-
connect hose.
Temperature Regulation
In order to reduce the risk of scald injury, the thermostat is
factory set to 49°C (120°F). The thermostat operates auto-
matically and can be adjusted to provide higher or lower
water temperature as needed. A mixing valve in connection
with a higher temperature setting should be used to reduce
risk of scald injury.
Figure 4: Wiring Diagram
IF WIRE HAS TO BE REPLACED IN THE FIELD,
USE ONLY TYPE TEW 105°C WIRE.
BOOSTER TANK
MUST BE
GROUNDED TO
THE ELECTRICAL
SUPPLY SERVICE.
BLACK
BLACK
WIRE CONNECTORS
CIRCULATOR
PUMP L1
120 VOLT SUPPLY
JUNCTION BOX
(AT CASING TOP)
THERMOSTAT
L2
DANGER
CAUTION
Increasing the thermostat setting above the pre-set tem-
perature may cause severe burns and consume exces-
sive energy. Hotter water increases the risk of scald injury.
IMPORTANT
RISK OF SCALDING. Hot water will cause third degree
burns in 6 seconds at 60°C (140°F), in 30 seconds at 54°
(130°F).