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with other gas fired appliances; the supply gas pressures shall
be measured at each water heater with all gas fired appliances
connected to a common main firing at full capacity.
On multiple water heater installations the supply gas line
regulators shall be adjusted to provide gas pressure to each
water heater within the minimum and maximum supply pressure
requirements listed in Table 3 on page 11 with all gas fired
appliances connected to a common gas main firing at full capacity.
NOTE:
A pressure drop of more than 1.5” W. C. (0.37 kPa) when
the Main Burner ignites is an indication of an inadequate supply
of gas and can lead to ignition failure, rough starts and/or rough
operation. If a drop of more than 1.5” W. C. (0.37 kPa) in supply
gas pressure occurs when the Main Burner ignites, ensure the
supply gas lines and regulator(s) are properly sized and installed.
See the requirements for Supply Gas Regulator and Gas Supply
Systems on page 13. See Supply Gas Line Installation on
page 39 and Supply Gas Regulator on page 13. Ensure all
requirements and installation instructions are maintained.
MANIFOLD GAS PRESSURE
The manifold pressure is non adjustable. The manifold gas
pressure is factory set and cannot be field adjusted. If the
manifold gas pressure readings taken on these models is off by
more than ± 0.3" W. C. from the listed values in Table 3 on page
11 call the technical support phone number listed on the back
cover of this manual for further assistance.
SUPPLY GAS PRESSURE ADJUSTMENT
Fire and Explosion Hazard
Turn off gas lines during installation.
Contact a qualified installer or service
agency for installation and service.
Excessive gas pressure to gas valve can
cause serious injury or death.
Do not use water heater with any gas
other than the gas shown on the rating
label.
Supply gas pressure shall be measured while the water heater is
not firing (static pressure)
AND
while the water heater is firing at
full capacity (dynamic pressure).
If the supply gas pressure to the water heater is not between the
required minimum and maximum values given in Table 3 on page
11 adjust the supply gas regulator as necessary. Adjust the supply
gas regulator(s) per the regulator manufacturer’s instructions to
achieve the required “static” and “dynamic” supply gas pressure.
Multiple Water Heater Installations:
In multiple water heater installations or in installations where
the installed water heater(s) share a common gas supply main
