40
GAS LINE CONNECTION
1. The water heaters covered by this manual are shipped from
the factory with 3/4 inch supply gas connections. The supply
gas line must not be smaller than 3/4 inch. Connect the supply
gas line to the water heater's 24 Volt Gas Valve in accordance
with all applicable local and national code requirements.
2. Depending on the developed equivalent length and/or the
number of appliances connected to a common main, the
size of the supply gas line may have to be increased, see
Gas Line Sizing on page 39. If the supply gas line must
be re-sized larger to accommodate increased supply gas line
lengths or multiple appliances use reducer couplings and
short pipe nipples to increase the supply gas line.
NOTE:
Make the transition to the larger supply gas line as
close to the supply gas connection as possible.
3. Apply thread sealing compounds (pipe dope/Teflon tape)
sparingly and only to the male threads of the pipe joints. Do
not apply sealing compound to the first two threads. Use pipe
dope or Teflon tape marked as being resistant to the action of
liquid petroleum (LP/propane) gases.
LOW GAS PRESSURE
SWITCH
COMBUSTION
BLOWER
SUPPLY GAS CONNECTION
FACTORY INSTALLED
TEE FITTING
SUPPLY GAS LINE CONNECTION
Figure 55
4. Use only a smooth jaw adjustable wrench as a back up
on the body of the 24 Volt Gas Valve when tightening the
first pipe nipple into the body of the valve.
DO NOT
use a
standard pipe wrench (Stillson wrench) with metal tooth jaws
as this may permanently damage the valve.
5. Use a standard pipe wrench (Stillson wrench) as a back up
on the first pipe nipple installed above when connecting other
fittings and pipe in the supply gas line to prevent the 24 Volt
Gas Valve on the water heater from twisting during installation.
6. To prevent damage, care must be taken not to apply too
much torque when connecting the supply gas line to the
water heater.
7. Install a sediment trap as shown in Figure 54 on page 39.
8. Install a Main Gas Shutoff valve in the supply gas line as
shown in Figure 54 on page 39.
NOTE:
Should overheating occur or the gas supply fail to shut
off, turn off the Main Gas Shutoff valve to the water heater.
GAS LINE LEAK TESTING
Fire and Explosion Hazard
Leak test gas connections before
placing water heater in operation.
Disconnect gas piping at main
gas shutoff valve before leak
testing heater.
Install sediment trap in
accordance with NFPA 54 or
CAN/CSA B149.1.
Use joint compound or Teflon tape
compatible with propane gas.
Any time work is done on the gas supply system perform a leak
test to avoid the possibility of fire or explosion.
1. For test pressures exceeding 1/2 psi (3.45 kPa) disconnect
the water heater and its Main Gas Shutoff Valve from the
gas supply piping system during testing, see Figure 54
on page 39. The gas supply line must be capped when
disconnected from the water heater.
2. For test pressures of 1/2 psi (3.45 kpa) or less, the water
heater need not be disconnected, but must be isolated from
the supply gas line by closing the Main Gas Shutoff Valve
during testing.
3. Paint all supply gas line joints and connections upstream of
the water heater with a rich soap and water solution to test
for leaks. Bubbles indicate a gas leak. Do not use matches,
candles, flame or other sources of ignition for this purpose.
4. Repair any leaks before placing the water heater in operation.
PURGING
Gas line purging is required with new piping or systems.
Purging should be performed per the current edition of NFPA 54
the National Fuel Gas Code or CAN/CSA B149.1 Natural Gas
and Propane Installation Code.
ELECTRICAL WIRING
All electrical work must be installed in accordance with the
National Electrical Code, ANSI/NFPA 70 or the Canadian
Electrical Code, CSA C22.1 and local requirements.
When installed, the water heater must be electrically grounded
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, CSA C22.1.
If any of the original wire as supplied with the water heater must
be replaced, it must be replaced with 105°C rated wiring or its
equivalent, except in the burner housing. In this case 200°C
rated wire must be used.
