Burnham CHG225 User Manual
Page 15
 
15
B. Removing an Existing Boiler From a Common Chimney
Read this only if the CHG boiler is replacing an existing boiler that is being removed from a common chimney.
This section does not apply to the installation of a CHG boiler.
In some cases, when an existing boiler is removed from a common chimney, the common venting system may
be too large for the remaining appliances. 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	horizontal	pitch	and	determine	there	is	no		 	
blockage or restriction, leakage, corrosion and other deficiencies which could cause an unsafe condition.
(c) Insofar as practical, close all building doors and windows and all doors between the space in which all 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 instructions. Adjust thermostat so the
appliance will operate continuously.
(e) Test for spillage at the draft hood relief opening after 5 minutes of main burner operation. Use the flame of
a match or candle, or smoke from a cigarette, cigar, or pipe.
(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 appliances to their previous condition of use.
(g) Any improper operation of the common venting system should be corrected so the installation conforms
with the National Fuel Gas Code, ANSI Z223.1. When re-sizing any portion of the common venting
system, the common venting system should be re sized to approach the minimum size as determined using
the appropriate tables in Part 11 of the National Fuel Gas Code, ANSI Z223.1.
warNINg
NEVEr COmmON VENT a Chg bOIlEr wITh OThEr aPPlIaNCEs
CauTION
VENT SySTEMS MADE By BuRNHAM, HEAT FAB, PRoTECH, AND Z-FLEx RELy oN GASkETS
FoR PRoPER SEALING. WHEN THESE VENT SySTEMS ARE uSED, TAkE THE FoLLoWING
PRECAuTIoNS:
• MAkE SuRE THAT GASkET IS IN PoSITIoN AND uNDAMAGED IN THE FEMALE END oF THE 
PIPE.
• MAkE SuRE THAT BoTH THE MALE AND FEMALE PIPES ARE FREE oF DAMAGE PRIoR To
assEmbly.
C. Vent / Intake System Assembly
1) General Assembly Notes:
a) Where the use of “silicone” is called for in the following instructions, use GE RTV 106 for the vent collar. Air
inlet piping sections are sealed with any general-purpose silicone sealant such as GE RTV102. PVC air
inlet piping sections are connected with PVC cement.
b)	 	Longitudinal	welded	seams	should	not	be	placed	at	the	bottom	of	horizontal	sections	of	exhaust	pipe.
c)	 	Do	not	drill	holes	in	vent	pipe.	
d)	 	Do	not	attempt	to	mix	vent	components	of	different	vent	system	manufacturers.
e)	 	In	some	cases,	there	are	differences	between	the	vent	system	installation	instructions	in	this	manual	and	
those in the vent system manufacturer’s manual. Where such differences exist, this manual takes
precedence over the vent system manufacturer’s manual.