Venting & Air - General; When Removing A Boiler From An Existing Common Vent System; Existing Vent Test Procedure - Williamson-Thermoflo GWC-070 Manual

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Venting & air — general
GWC boilers must be vented and
supplied with combustion and ven-
tilation air using piping and methods
described in this manual
Every boiler must have its own vent
DO NOT
common vent with any other
appliance.
Inspect finished vent and air piping
thoroughly to ensure all are airtight
and comply with the instructions
provided and with all requirements of
applicable codes.
Failure to provide a properly-installed
vent and air system will cause severe
personal injury or death.
If the vent/air piping configurations
covered in the GWC boiler manual
cannot be applied for a particular
installation, contact Williamson-
Thermoflo for assistance. Other con-
figurations may be available.
Where vent piping is routed through
an unheated space
1 inch of foil-faced fiberglass insulation
on the length of the vent pipe in the
unheated space.
Installations must comply with local
requirements and with the National
Fuel Gas Code, ANSI Z223.1 for U.S.
installations or CSA B149.1 or B149.2
for Canadian installations.
Use only the materials listed in this
manual for vent and air pipe and fit-
tings. See Figure 40, page 33.
If used, a masonry chimney can
ONLY be used as a PIPE CHASE for
vent and air pipes
piping must be installed as instructed
in this manual and all joints must be
sealed. The chimney must be used only
for GWC boilers. NO OTHER appli-
ance or fireplace can be connected to
the chimney. The chimney must be
straight, with no offsets, and the vent
and air piping materials must comply
with this instruction manual. The
chimney must be fitted with a sealed
access opening, through which the in-
terior of the chimney can be inspected.
The chimney (and liner, if installed)
must be inspected at least once annu-
ally to verify condition.
Failure to comply could result in severe
personal injury, death or substantial
property damage.
Part number 550-142-786/0712
-
fired water boiler
When removing a boiler from an existing
common vent system
.
The GWC boiler cannot be common vented with any other ap-
pliance.
.
boiler CANNOT use the existing common vent. The GWC boiler requires
its own vent and air piping, as specified in this manual. This may cause a
problem for the appliances that remain on the old common vent, because
the vent may be too large. The following test, required by ANSI Z21.13,
is intended to check for proper operation of the appliances remaining on
the old common vent system.
Vent system verification
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. Seal any unused open-
ings in the common venting system.

Existing vent test procedure

, apply minimum
(The following is intended to test whether the appliances
remaining on an existing vent system will operate
satisfactorily.)
1. Visually inspect the venting system for proper size and horizontal pitch
2. Test vent system — Insofar as is practical, close all building doors and
— The vent and air
3. Place in operation the appliance being inspected. Follow the lighting in-
4. Test for spillage at draft hood relief opening after 5 minutes of main
5. After it has been determined that each appliance remaining connected
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 re-sizing 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.
— Boiler Manual
When an existing boiler is replaced with a GWC boiler, the GWC
and determine there is no blockage or restriction, leakage, corrosion or
other deficiencies which could cause an unsafe condition.
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 oper-
ate at maximum speed. Do not operate a summer exhaust fan. Close
fireplace dampers.
structions. Adjust thermostat so appliance will operate continuously.
burner operation. Use the flame of a match or candle, or smoke from
a cigarette, cigar, or pipe.
to the common venting system properly vents when tested as outlined
herein, return doors, windows, exhaust fans, fireplace dampers, and any
other gas-burning appliance to their previous conditions of use.
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