Venting For Multiple Boilers - Patterson-Kelley P-K STORM ST-8000 Installation And Owner's Manual

Venting for Multiple Boilers

While the vent design parameters outlined in
in a combined vent system adds a significant degree of complexity. Therefore, venting systems for
multiple appliances shall be designed by experienced and knowledgeable venting professionals. The
venting system shall be designed to prevent backflow of exhaust gas through idle appliances. For
combined breeching installations, please follow recommendations of a qualified venting
engineer/manufacturer.
Patterson-Kelley recommends that common venting systems be designed for a maximum continuous
exhaust pressure of -0.04" W.C. when measured in the common vent. Locking inline dampers are
recommended on the exhaust connection of each individual appliance in order to control the exhaust
back pressure within the appliance and upstream of this damper. The -0.04" W.C. in the common flue
will also help make sure the exhaust gases from an online appliance does not backflow through offline
appliance(s).
In addition, Patterson-Kelley also recommends the use of motorized combustion air dampers in the
combustion air intake ductwork of each individual appliance. When an appliance is offline, its
combustion air damper will remain closed which will also help prevent the backflow of flue gases from
online appliances. Please refer to
Revised: February 2, 2024
Released: February 2, 2024
3.4
3.4.5 for more information.
If the common venting system uses a draft inducer fan or damper
device, this MUST be interlocked with the appliances. In the event this
draft inducer device fails, the interlock circuits to the appliances must be
opened in order to prevent operation. Failure to do so could result in
appliance operation under excessive back pressure conditions which
could result in damage to the appliance and lead to serious injury or
death.
The design of any common venting system MUST prevent backflow of
combustion gases through offline boilers or water heaters. Failure to do
so could result in damage to the appliance and lead to serious injury or
death
.
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All Rights Reserved.
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and 3.5 still apply, achieving those same parameters
Installation and Owners Manual Rev G.docx
®
P-K Storm Gas Fired Boiler
2691000403 P-K Storm ST2500-ST8000
Page 35