GWS-090E
Gas-Fired Water Boiler –
Boiler Manual
4
Part Number 550-110-737/1108
1 Prepare boiler location
continued
Failure to follow all instructions can result in flue gas
spillage and carbon monoxide emissions, causing
severe personal injury or death.
Do not install the GWS-090E into a common vent
with any other appliance. This will cause flue gas
spillage or appliance malfunction, resulting in pos-
sible severe personal injury, death or substantial
property damage.
GWS-090E boilers can only be direct-vent vented.
They cannot be chimney-draft vented or direct-ex-
haust vented. See GWS Venting Manual for detailed
installation instructions.
If you are removing an existing boiler from a shared
venting system, the GWS-090E boiler cannot share
the vent system (it requires its own vent). You must
test each appliance remaining on the old common
vent system individually to verify the vent system
still operates adequately. Follow guidelines below.
When removing boiler from existing common vent
system:
At the time of removal of an existing boiler, the following steps
shall be followed with each appliance remaining connected to
the common venting system placed in operation, while the other
appliances remaining connected to the common venting system
are not in operation.
a. Seal any unused openings in the common venting system.
b. Visually inspect the venting system for proper size and hori-
zontal pitch and determine there is no blockage or restriction,
leakage, corrosion or other deficiencies which could cause an
unsafe condition.
c. Test vent system — Insofar as is practical, close all building
doors and windows and all doors between the space in which
the appliances remaining connected to the common venting
system are located and other spaces of the building. Turn
on clothes dryers and any appliance not connected to the
common venting system. Turn on any exhaust fans, such as
range hoods and bathroom exhausts, so they will operate at
maximum speed. Do not operate a summer exhaust fan. Close
fireplace dampers.
d. Place in operation the appliance being inspected. Follow the
lighting/operating instructions. Adjust thermostat so appliance
will operate continuously.
e. Test for spillage at draft hood relief opening after 5 minutes of
main burner operation. Use the flame of a match or candle.
f. After it has been determined that each appliance remaining
connected to the common venting system properly vents when
tested as outlined above, return doors, windows, exhaust fans,
fireplace dampers, and any other gas-burning appliance to
their previous conditions of use.
Any improper operation of common venting system should be
corrected so the installation conforms with the National Fuel
Gas Code, ANSI Z223.1 – latest edition. Correct by resizing to
approach the minimum size as determined using the appropriate
tables in Part 11 of that code. Canadian installations must comply
with B149.1 or B149.2 Installation Code.
GWS-090E special vent system required
Vent system
The GWS-090E boiler requires a special vent system, designed
for pressurized venting. Model GWS-090E is rated ANSI Z21.13
Category IV (pressurized vent, likely to condense in the vent).
You may use any of the direct vent systems (combustion air
ducted to boiler) covered in GWS Venting Manual included in
the boiler envelope assembly. The GWS vent starter is a special
item, designed only for GWS and GWS-90E, available from each
vendor. Do not attempt to connect the vent to a GWS-090E boiler
with any other means.
DO NOT mix components from different systems.
The vent system could fail, causing leakage of flue
products into the living space.
Vent termination and combustion air supply
The GWS-090E boiler may be vented through the roof or through
a side wall. Follow the appropriate instructions in the GWS Venting
Manual for the vent system chosen. The maximum vent length
depends on boiler size. Refer to the GWS Venting Manual to
determine acceptable vent length.
Combustion air for the GWS-090E boiler must be ducted directly
to the boiler from outside. For outside air (direct vent installa-
tion), two options are available for the flue/air termination. The
air supply must ALWAYS terminate at the same location as the
flue, using either:
1. Vertical direct vent installation — Obtain the Through-Roof or
Through-Unused Chimney Termination Kit. Refer to the GWS
Venting Manual, packed with the kit and to the vent manufac
-
turer’s instructions for the vent material chosen.
2. Sidewall direct vent installation — Use the Vent/Air Intake
Termination Kit shipped with the boiler. Refer to the GWS
Venting Manual shipped with the boiler.
Vent system
