QHT BIASI B10 Series B3-B9, Manual And Installation

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The B10  boiler is a high efficiency unit that requires proper venting. The boiler must 

be vented to the outdoors by means of a tile lined masonry or a approved pre-fabricated 
chimney of the size and height recommended by the manufacturer or by a listed "power 
venting" unit which provides draft by mechanical means.  In many installations, particularly 
older interior and most exterior chimneys, a corrosion resistant liner should be installed and 
may be required by code.  Please consult liner manufacturer for the appropriate chimney 
liner. 
         The chimney discharge opening must be located at least 24 inches above any part of 
the building structure within 4 feet of the chimney.  Be sure the chimney and smoke pipe 
won't become obstructed by squirrels, bird nests, soot buildup, chimney liner deterioration, 
etc..  If using a "power venter" system, it is suggested that it should be installed on the 
leeward side of the house.  (Please consult with manufacturer of "power venter" for 
requirements concerning clearances from combustibles and distances from doors and 
windows.)  The "venter" must be installed by a licensed burner  mechanic and done in 
accordance with local codes. This is a very low stack temperature boiler (350F gross temp.) 
so caution should be used when connecting to an outside built chimney.  Should you have 
concern that the flue gases could condense, then you should consider lining the chimney or  
using a listed, "power venting" or " direct venting unit".  If "power venting" is used to 
discharge flue gases, then the power vent  unit should be equipped with a postpurge control 
such as a delay-off, timing control to  prevent problems with fogging and  nozzle post drip.   
 

The exhaust pipe connection from the boiler to the chimney should be as short as 

possible, with a minimum number of elbows. The vent pipe must have a vertical rise of at 
least 1/4 inch per foot of horizontal run. The vent pipe must be of the same diameter as the 
flue outlet on the boiler. The chimney connector should have a minimum thickness of 26 
gauge, corrosion resistant (galvanized) steel, and be assembled with a minimum of three (3) 
sheet-metal screws in each joint. In some one and two story houses, a barometric draft 
control isn't required as the B-10 is designed to be pressure-fired.  However in high draft 
situations which exceed the flue gas resistance through the boiler, a barometric draft control 
is recommended.  The over fire draft should be positive and between 0 and .06 inches of 
water column.  The draft at the breech should be enough to overcome the resistance 
through the boiler.   

7.  Exhaust Venting

7.1 Common Exhaust Venting Cont. 

Common vent exhaust: 
 

If this boiler is replacing one that was part of a common venting system, it is 

likely that the vent is to large to vent the appliances still attached to it.  To prevent this, 
at the time of removal, the following steps shall be followed with each appliance re-
maining connected to the common venting system.  Place each appliance in opera-
tion, while the other appliances remaining connected to the common venting system 
are not in operation. 
 

1.Seal any unused openings in the common venting system. 
2.Visually inspect the venting system for proper size and horizontal pitch and deter-

mine there is no blockage or restriction, leakage, corrosion and other deficiencies 
which could cause an unsafe condition.