Installation & Operation Manual
38
7
Gas connections
Gas pressure
The gas pressure must remain between 4 inches w.c. (natural),
8 inches w.c (LP) minimum and 14 inches w.c. (natural and LP)
maximum during stand-by (static) mode and while in operating
(dynamic) mode. If an in-line regulator is used, it must be a
minimum of 10 feet from the Armor water heater. It is very
important that the gas line is properly purged by the gas supplier
or utility company. Failure to properly purge the lines or
improper line sizing, will result in ignition failure.
The problem is especially noticeable in NEW LP installations
and also in empty tank situations. This can also occur when a
utility company shuts off service to an area to provide
maintenance to their lines.
DETAIL
LOOSEN THE SET SCREW ONE (1) FULL TURN AND
PLACE THE MANOMETER TUBING OVER THE
PRESSURE TAP
Figure 7-5
Inlet Gas Supply Check - Models 150 - 285
DETAIL
LOOSEN THE SET SCREW ONE (1) FULL TURN AND
PLACE THE MANOMETER TUBING OVER THE
PRESSURE TAP
Figure 7-6
Inlet Gas Supply Check - Model 399
DETAIL
LOOSEN THE SET SCREW ONE (1) FULL TURN AND
PLACE THE MANOMETER TUBING OVER THE
PRESSURE TAP
Figure 7-7
Inlet Gas Supply Check - Model 500
DO NOT adjust or attempt to measure gas
valve outlet pressure. The gas valve is
factory-set for the correct outlet pressure.
This setting is suitable for natural gas and
propane, requiring no field adjustment.
Attempting to alter or measure the gas valve
outlet pressure could result in damage to the
valve, causing potential severe personal
injury, death, or substantial property
damage.
Failure to follow all precautions could result
in fire, explosion, or death!
WARNING
WARNING
Gas valve replacement
The gas valve MUST NOT be replaced with a conventional gas
valve under any circumstances. As an additional safety feature,
this gas valve has a flanged connection to the venturi and blower.
High and low gas pressure switches
High and low gas pressure switches are an added level of safety
and can be used to monitor manifold pressure along with inlet
gas supply pressure.
The high gas pressure switch is used to monitor the manifold
pressure. If the manifold pressure exceeds the setting indicated
on the switch, the gas pressure switch will trip and prevent the
appliance from operating.
The low gas pressure switch monitors the inlet gas supply
pressure. The low gas pressure switch will prevent the unit from
operating until a minimum pressure equal to the setting of the
switch is obtained.
The low gas pressure switch should be set at the minimum gas
supply pressures for both natural and propane gas, see the
Natural and Propane Gas Sections on page 36.
The high gas pressure switch should be set at the minimum gas
supply pressure the switch will allow.
17. Check burner performance by cycling the system while
you observe burner response. The burner should ignite
promptly. Flame pattern should be stable. Turn system
off and allow burner to cool, then cycle burner again to
ensure proper ignition and flame characteristics.
