Check Inlet Gas Pressure - Westinghouse WBRE80 User Manual

Never use an open flame (match or lighter) to check for gas
leaks. Use a soapy solution to test connection. Failure to use
a soapy solution test or check gas connection for leaks can
result in substantial property damage, severe personal injury,
or death.
Use two wrenches when tightening gas piping at the boiler:
One to prevent the boiler gas line from turning. Failure to
prevent the boiler gas connection from turning could result
in damage to the gas line components, substantial property
damage, severe personal injury, or death.
CSA or UL listed flexible gas connections can be used when
installing the boiler. Flexible gas connections have different
capacities and must be sized correctly for the connected
boiler firing rates. Consult with the flex line supplier to assure
the line size is adequate for the job. Follow local codes for
proper installation and service requirements.
B. Check Inlet Gas Pressure
The gas valve is equipped with an inlet gas pressure tap that
can be used to measure the gas pressure to the unit. To check
gas pressure, perform the steps listed below:
1. IMPORTANT! Before you connect to the inlet pressure,
shut off the gas and electrical power to unit.
2. Loosen the pressure tap with a small screwdriver. Refer to
Figure 27 for location.
3. Each unit is equipped with a needle valve that will accept a
5/16 ID hose to connect to a digital manometer or liquid gauge
to measure incoming pressure from 0-35" w.c. See Figure 27.
4. Turn on the gas and power up the unit.
5. Put the unit into manual test mode (details on test mode are
in Part 10). In test mode, monitor pressure to assure it does not
drop below 1 inch from its idle reading. If gas pressure is out
of range or pressure drop is excessive, contact the gas utility,
gas supplier, qualified installer, or service agency to determine
correct action that is needed to provide proper gas pressure
to the unit. If Gas Pressure is within normal range proceed to
Step 6.
6. Exit test mode, then turn power off and shut off gas supply
at the manual gas valve before disconnecting the hose from
the gas monitoring device. Tighten screw on the pressure tap
and turn gas on. Check for leaks with soapy solution. Bubbles
will appear on the pipe to indicate a leak is present.
Table 14 - Gas Pipe Sizing / BTU's per Hour
Ensure the pressure tap screw is properly tightened to prevent
gas leaks. Failure to do so could cause substantial property
damage, severe personal injury, or death.
The gas piping must be sized for the proper flow and length of
pipe to avoid pressure drop. The gas meter and regulator must be
properly sized for the total gas load. If you experience a pressure
drop greater than 1" w.c. (.87 kPa), the meter, regulator or gas
line may be undersized or in need of service. You can attach a
manometer to the incoming gas drip leg after removing the cap.
The gas pressure must remain between 3.5" (.87 kPa) and 14"
(3.5 kPa) 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 boiler. It is very important that the gas line is properly
purged by the gas supplier or utility. Failure to properly purge
the lines, or improper line sizing, will result in ignition failure.
This problem is especially noticeable in NEW LP installations
and empty tank situations. This situation can also occur
when a utility company shuts off service to an area to provide
maintenance to their lines. This gas valve must not be replaced
with a conventional gas valve under any circumstances.
DO NOT adjust or attempt to measure gas valve outlet pressure.
The gas valve is factory-set for the correct outlet pressure and
requires no field adjustment. Attempts by the installer to adjust
or measure the gas valve outlet pressure could result in damage
to the valve and cause substantial property damage, severe
personal injury, or death.
Ensure that the high gas pressure regulator is as least 6 – 10
feet upstream of the appliance. Failure to do so could result in
substantial property damage, severe personal injury, or death.
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WHL-052 Rev. 4.28.16