John Wood Takagi - 320H-520H - Manual (Page 15)

15
Water connections
FOR YOUR SAFETY, READ
BEFORE OPERATING
Do not use this water heater if any part has been sub-
mersed under water. Immediately call a licensed profes-
sional to inspect the water heater and to replace any
damaged parts.
All pipes, pipe fittings, valves and other components,
including soldering materials, must be suitable for pota-
ble water systems.
A manual shut off valve must be installed on the cold
water inlet to the water heater between the main water
supply line and the water heater.
In addition, a manual shut off valve is also recommended
on the hot water outlet of the unit. If the water heater is
installed within, or subjected to, a closed loop water sys-
tem, a thermal expansion tank must be installed.
Before installing the water heater, flush the water line
to remove all debris, and after installation is complete,
purge the air from the line. Failure to do so may cause
damage to the heater.
There is a wire mesh filter within the cold inlet to trap
debris from entering your heater. This will need to be
cleaned periodically to maintain optimum flow.
Water intlet
(Cold) Gas intlet
Condensate
drain port
Water outlet
(Hot)
WARNING
Do not reverse the hot outlet and cold inlet
connections to the 520H Water Heater. This
will not properly active the water heater.
Pressure Relief Valve
The 520H has a high-temperature shut off switch built in as
a standard safety feature (called a Hi-Limit switch) therefore
a “pressure only" relief valve is required.
This unit does not come with an approved pressure relief
valve.
An approved pressure relief valve must be installed on
the hot water outlet.
The pressure relief valve must conform to ANSI Z21.22
or CAN 1-4.4 and installation must follow local code.
The discharge capacity must be at least 199,000 BTU/
h.
The pressure relief valve needs to be rated for a maxi-
mum of 150 psi.
1.
2.
3.
4.
5.
1.
2.
3.
4.
5.
The discharge piping for the pressure relief valve must
be directed so that the hot water cannot splash on any-
one or on nearby equipment.
Attach the discharge tube to the pressure relief valve and
run the end of the tube to within 150mm (6 in.) from the
floor. This discharge tube must allow free and complete
drainage without any restrictions.
If the pressure relief valve installed on the 520H dis-
charges periodically, this may be due to a defective ther-
mal expansion tank or defective pressure relief valve.
The pressure relief valve must be manually operated
periodically to check for correct operation.
Hot outlet Cold intlet Gas intlet
As close as
possible
Pressure
Relief Valve
Condensate Drain
The 520H does not include a built-in condensate neutral-
izer cartridge for reducing the pH level of condensate
water. If local codes dictate that condensate must be
neutralized prior to drainage, a condensate neutralizer
must be installed. An accessory Neutralizer assembly is
sold separately.
In the absence of applicable local codes and regulations,
the manufacturer recommends that condensate be dis-
posed of into a standard drain. Connect a drain tube from
the condensate drain port (shown below) located on the
bottom of the water heater to a standard drain.
Follow all code requirements of the local
authority on condensate neutralizers and
whether or not they are required for the
installation.
Condensate
drain port
6.
7.
8.
9.
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