Supply Gas Pressure Adjustment; Manifold Gas Pressure Adjustment - State Water Heaters SUF-100-250 Instruction Manual

supply gas pressure adjustment

Fire and Explosion Hazard
Do not use water heater with any gas
other than the gas shown on the rating
label.
Excessive gas pressure to gas valve can
cause serious injury or death.
Turn off gas lines during installation.
Contact a qualified installer or service
agency for installation and service.
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 4 on page
14 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 appliance installations:
in multiple water heater installations or in installations where
the installed water heater(s) share a common gas supply main
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 4 on page 14 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
Supply Gas Line on page 14. See Supply Gas Line Installation on
page 39 and Supply Gas regulator installation on page 40. Ensure
all requirements and installation instructions are maintained.

manifold gas pressure adjustment

Under no circumstances should the
input exceed the rate shown on the
water heater's rating label.
Overfiring could result in fire or
explosion.
Gas and carbon monoxide detectors are
available.
Breathing Hazard - Carbon Monoxide Gas
Breathing carbon monoxide can cause brain damage or
death. Always read and understand instruction manual.
Ensure the "dynamic" supply gas pressure is above the minimum
requirements in Table 4 on page 14 before any adjustments are
made to the manifold gas pressure. Attempts to adjust manifold
gas pressure during periods of low supply gas pressure could
result in overfiring when the supply gas pressure returns to
normal. See Supply Gas Pressure Adjustment on this page.
note: manifold gas pressure is non-adjustable on SUF 100 199
and SUF 100 250 models. The manifold gas pressure on these
models 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 4 on page 14 call the
technical support phone number listed on the back cover of this
manual for further assistance.
Follow the steps below to adjust the manifold gas pressure on
SUF 100 120 and SUF 100 150 models:
1. Follow the instructions for initial Start Up on page 52 to connect
manometers to the supply and manifold gas pressure taps
and to start the water heater.
2. remove the manifold gas pressure regulator cover screw,
see Figure 57 on page 53.
3. Using a small flat tip screw driver turn the adjustment screw
clockwise to increase manifold gas pressure and counter
clockwise to decrease manifold gas pressure.
note: Turn the manifold gas pressure adjustment screw
in small increments (no more than 1/4 turn) and allow the
manifold gas pressure to stabilize for several minutes before
making further adjustments.
4. replace the gas pressure regulator cover screw.
5. Cycle the burner on and off several times to check operation.
54
Fire and Explosion Hazard
Under no circumstances should
the input exceed the rate shown
on the water heater's rating label.
Overfiring could result in damage to
the water heater and sooting.
Gas and carbon monoxide detectors
are available.