Gas Pressure; Gas Valve Replacement - Lochinvar Knight XL 100 Series Installation & Operation Manual

8
Gas connections
When re-tightening the set screw, be sure
⚠ WARNING
to tighten securely to prevent gas leaks.
Do not check for gas leaks with an open
flame -- use the bubble test. Failure to use
the bubble test or check for gas leaks can
cause severe personal injury, death, or
substantial property damage.
14. Turn on the gas supply at the manual gas valve.
15. Turn the power switch to the "ON" position.
16. Adjust the temperature set point on the display of
the SMART TOUCH control module to the desired
water temperature so the appliance will call for heat.
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.
Figure 8-4 Inlet Gas Supply Check - Model 400 - 500
DIR #2000585203 00
(continued)
DETAIL
LOOSEN THE SET SCREW ONE (1)
FULL TURN AND PLACE THE
MANOMETER TUBING OVER
THE PRESSURE TAP.
Installation & Operation Manual
Figure 8-5 Inlet Gas Supply Check - Models 650 - 1000
DIR #2000585203 00

Gas pressure

The gas pressure must remain between 4 inches w.c. (.99
kPa) minimum and 14 inches w.c. (3.5 kPa) maximum for
Natural gas and between 8 inches w.c. (1.9 kPa) minimum
and 14 inches w.c. (3.2 kPa) maximum for LP gas during
standby (static) mode and while in operating (dynamic)
mode. If an in-line regulator is used, it must be a minimum
of 10 feet (3 m) from the Knight XL boiler. 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.

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.
⚠ WARNING Failure to follow all precautions could
result in fire, explosion, or death!
DO NOT adjust gas valve outlet pressure.
⚠ WARNING
Attempting to alter the gas valve outlet
pressure could result in damage to the
valve, causing potential severe personal
injury, death, or substantial property
damage.
DETAIL
REMOVE THE 1/8" (3 MM) PIPE PLUG ON
THE INLET FLANGE TO THE VALVE AND
INSTALL A SUITABLE 1/8" (3 MM) FITTING
(FIELD SUPPLIED) FOR THE MANOMETER
TUBING.
51