John Wood Direct Vent Models No Longer in Production - Manual (Page 6)

High Rise Vent Pipe Arrangement
Figure 3M
When the height H (From vent terminal center line to bot-
tom of heater) is over 2.28m (90 in.), it is a high rise vent
pipe arrangement. The minimum distance “D” from the
center of the water heater to the outside wall surface is
560mm (22 in.), and the maximum height of “H” is 3.66m
(12 ft.).
IV) GAS CONNECTIONS
Install the gas piping as indicated in Figure 2A. Use only
new pipe and fittings with sound, clean-cut pipe threads.
Sealing compound must conform to the applicable code
for pipe sealing compound approved for use with natural
gas and propane. Use gas piping of adequate sizing to
ensure full gas input. All piping must comply with all local
codes. In the absence of local codes, piping must comply
with the rules stated by the applicable CSA B149 Natural
Gas and Propane Installation Code or ANSI Z223.1
National Fuel Gas Code. The final connection to the gas
control valve is made using 1/2 in. NPT pipe.
Inlet gas pressure to the appliance must not exceed the
gas pressures marked on the rating plate; 1.74 kPa (7 in.
water column) for natural gas, 3.5 kPa (14 in. water col-
umn) for L.P. gas. The minimum supply pressure for the
purpose of input adjustment is 0.25 kPa (1 in. water col-
umn) above manifold pressure.
The appliance and its individual shut-off valve must be
disconnected from the gas supply piping system during
any pressure testing of that system at test pressure in
excess of 3.5 kPa (14 in. water column).
The appliance must be isolated from the gas supply pip-
ing system by closing its individual manual shut-off valve
during any pressure testing of the gas supply piping sys-
tem at test pressures equal to, or less than 3.5 kPa (14
in. water column).
The appliance and its gas connection must be leak test-
ed before placing the appliance in operation. It is impor-
tant to have a readily accessible manual shut-off valve in
the gas line supplying the water heater. This shut-off
valve must be close to the heater. In addition, a drip leg
must be installed ahead of the gas control valve to help
trap sediment and foreign material.
A ground-joint union must be installed ahead of the gas
valve to permit easy removal of the unit. All leak testing
must be done with a soapy water solution.
NEVER USE A MATCH OR OPEN FLAME TO TEST
FOR GAS LEAKS. A FIRE OR EXPLOSION COULD
RESULT.
V) WATER PIPING
Pipes and fittings should be installed in compliance with
the installation drawing. Check for dip tube in cold water
fitting before connection of hot and cold water lines. It is
recommended that a shut-off valve be located in the cold
water supply line in close proximity to the cold water inlet
of the water heater. Show the user where this water shut-
off valve is installed and how to use it to shut the water
supply to the heater off.
Connect the cold water supply (3/4 in. NPT) to the fitting
marked “COLD”, the hot water outlet (3/4 in. NPT) to the
fitting marked “HOT”. Do not apply heat to either of these
fittings as they contain a nonmetallic tube. When making
these connections, always use a good grade of pipe joint
compound and be certain that all fittings are tight. See
installation drawing (Figure 2A).
After piping has been installed, allow tank to fill with water
and check connections for leaks. To ensure complete fill-
ing of the tank, allow air to exit by opening the nearest hot
water faucet until a constant flow of water is obtained.
- 6 -
H
TO BOTTOM
OF HEATER
D
WALL THICKNESS
254mm
(10 in.)
(REF)