22
3.11.1. Gas Supply Connection
A
A
CAUTION:
The heater must be disconnected from the
gas supply during any pressure testing of the gas supply
system at test pressures in excess of 1/2 psi (3.45 kPa).
During any pressure testing of the gas supply piping
system at test pressures of 1/2 psi (3.45 kPa), or less, the
heater must be isolated from the gas supply piping system
by closing the upstream manual shut-off valve. Relieve
test pressure in the gas supply line prior to re-connecting
the heater and its manual shut-off valve to the gas supply
line.
FAILURE TO FOLLOW THIS PROCEDURE MAY
DAMAGE THE GAS VALVE.
Over-pressurized gas valves are not covered by warranty.
The heater and its gas connections shall be leak-tested
before placing the appliance in operation. Use soapy
water for leak test. DO NOT use an open flame.
MUST BE SUPPLIED BY INSTALLER
MANUAL BALL VALVE
UNION
ELBOW
WRENCHING NIPPLE
SEDIMENT TRAP
REAR JACKET
ZERO GOVERNOR
ON/OFF COMBO VALVE
MANUAL SHUTOFF
VALVE
STREET
ELBOW 1"
Figure 23. Gas Supply Connection
A
A
CAUTION:
Only sealant tape or a pipe compound rated
for use with natural and propane gases is recommended.
Apply sparingly only on male pipe ends, leaving the two
end threads bare.
A
A
CAUTION:
Support gas supply piping with hangers,
not by the heater or its accessories. Make sure the gas
piping is protected from physical damage and freezing,
where required.
3.11.2.
Gas Supply Pressure
A minimum of 4" WC and a maximum of 10.5" WC gas
pressure is required under load and no-load conditions
for natural gas at the heater. A minimum of 4" WC and a
maximum of 13" WC is required for propane gas at the
heater. The gas pressure regulator(s) supplied on the
heater is for low-pressure service. If upstream pressure
exceeds these values, an intermediate gas pressure
regulator, of the lockup type, must be installed.
When connecting additional gas utilization equipment
to the gas piping system, the existing piping must be
checked to determine if it has adequate capacity for the
combined load.
A
A
CAUTION:
For proper operation, no more than a 30%
drop in gas supply pressure from no-load to full-load
conditions is acceptable. Under no circumstances should
the pressure be outside the listed operational range.
When connecting additional gas utilization equipment
to the gas piping system, the existing piping must be
checked to determine if it has adequate capacity for the
combined load.
The gas valve pressure regulator on the heater is nominally
preset as noted in
Table N
.
During normal operation, carbon dioxide should be
9.0% ± 0.5% at full fire for natural gas and 10.2% ± 0.5%
for propane gas. Carbon monoxide should be less than
100ppm.
Model
No.
1-1/4" NPT
1-1/2"
NPT
2" NPT
2-1/2"
NPT
N
P
N
P
N
P
N
P
1005A
35
(10)
55
(17)
35
(10)
90
(27)
125
(38)
300
(91)
300
(91)
1505A
10
(3)
15
(5)
15
(5)
25
(7)
60
(18)
150
(46)
150
(46)
275
(84)
2005A
35
(10)
90
(27)
85
(26)
210
(64)
Natural Gas – 1,000 BTU/ft3
, 0.60 specific gravity at 0.5". WC pressure drop.
Propane Gas – 2,500 BTU/ft3
, 1.53 specific gravity at 0.6" WC pressure drop.
Table M.
Maximum Equivalent Gas Pipe Length (ft./m)
Model No.
Manifold Gas Pressure
(High Fire Values)
Natural Gas
Propane Gas
1005A
-4.6
-6.6
1505A
-7.1
-8.0
2005A
-2.6
-9.3
NOTE: Manifold pressures should be ±0.2" WC.
Table N.
Manifold Gas Pressure Settings
