Gas Pressure; Gas Valve Replacement - Lochinvar 81 - 286 Installation And Operation Manual

7
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 control panel of
the SMART SYSTEM 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 7-4 Inlet Gas Supply Check
LOOSEN THE SET SCREW ONE (1) FULL TURN
AND PLACE THE MANOMETER TUBING OVER
THE PRESSURE TAP.
(continued)

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 Knight 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
WARNING
DETAIL
Installation & Operation Manual
Failure to follow all precautions could
result in fire, explosion, or death!
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.
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