John Wood Takagi - 910 - Manual (Page 12)

12
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 910.
In addition, a manual shut off valve is also recommended
on the hot water outlet of the unit. If the 910 is installed
within, or subjected to, a closed loop water system, 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.
CAUTION
Do not reverse the hot outlet and cold inlet
connections to the 910 Water Heater. This
will not activate the water heater.
Hot outlet
Cold inlet
Gas inlet
Pressure
Relief
Valve
1.
2.
3.
4.
5.
Pressure Relief Valve
The 910 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 380,000 BTU/
h.
The pressure relief valve needs to be rated for a maxi-
mum of 150 psi.
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 910 discharg-
es periodically, this may be due to a defective thermal
expansion tank or defective pressure relief valve.
The pressure relief valve must be manually operated
periodically to check for correct operation.
When ASME model is installed, the pressure relief valve
should be conformed and installed in accordance with
ASME code.
For the ASME model, the pressure relief valve must
conform to and be installed in accordance with ASME
code.
Hot outlet
Cold inlet
Gas inlet
Pressure
Relief
Valve
As close
as possible
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.