Patterson-Kelley MACH-05 User Manual

 

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The MACH Series Boilers are also certified for 
operation with a sealed combustion air and pressurized 
venting system.  Such a system employs a sealed 
combustion air intake duct leading from outdoors and 
a sealed exhaust vent terminating outdoors.  Air flow 
through the system is maintained by the fan inside the 
boiler assembly.  

 

Installation must conform to the vent manufacturer's 
instructions in all respects including joining, 
clearances, fastening, fire-stopping, and other matters.   

Vent ductwork may be run horizontally or vertically if 
so certified. 

 

3.6.7  Removing an Existing Boiler  
(from a common venting system) 

When an existing boiler is removed from a common 
venting system, the common venting system is likely 
to be too large for proper venting of the appliances 
remaining connected to it. 

At the time of removal of an existing boiler, while the 
other appliances remaining connected to the common 
venting system are not in operation, the following 
steps should be followed with each appliance 
remaining connected to the common venting system 
placed 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 determine that there is no 
blockage or restriction, leakage, corrosion or other 
deficiency which could cause an unsafe condition. 

3.  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 appliances 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. 

4.  Place the appliance being inspected in operation. 

Follow the lighting instructions.  Adjust the 
thermostat so that the appliance will operate 
continuously. 

5.  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. 

6.  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 the common venting 
system should be corrected so the installation 
conforms with the National Fuel Gas Code, ANSI 
Z223.1 and CSA B149 Installation Code.  When 
resizing any portion of the common venting system, 
the common vent system should be resized to 
approach the minimum size as determined using the 
appropriate tables. 

 

Four basic configurations for the intake/exhaust may 
be used.  Refer to Section 3.6.3 for required 
clearances for all terminations shown in the four 
following figures.