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11
Step 3
Negative
Pressure
Make-up Air
Negative Pressure warning
: When negative
pressure is present, an atmospherically vented
fireplace (with a draft hood) may not function
properly and it may down draft. In the case of a
gas appliance, spillage of the combustion gases
may occur.
This may create a dangerous
carbon
monoxide situation in the house.
The causes of negative pressure to a house can
include the following:
Stack effect in the building.
Exhaust only appliances (mechanically and
atmospherically vented).
Inadequate make-up air (which is increasingly
more prevalent in new construction).
It is recommended that all natural venting non-air
tight gas fireplaces have outside air connected to
them. It is also recommended that the building be
mechanically or passively balanced to allow
atmospherically vented appliances, such as top
vented gas fireplaces with draft hoods, to draft
properly. If the home experiences negative
pressure or is likely to experience negative
pressure, connection to an outside air source is
mandatory.
This fireplace will operate correctly only if adequate
ventilation is provided to allow proper draft to the
fireplace system. Hearth Technologies assumes
no responsibility for the improper performance of
the fireplace system caused by inadequate draft
due to environmental conditions, down drafts, tight
sealing construction of the structure, or
mechanical exhausting devices which create a
negative air pressure within the structure where
the fireplace is located.
Installing Optional Outside Make-up Air:
This
unit is equipped to accept outside air. By using
outside make-up air, the amount of room air used
for combustion will be reduced. It is recommend-
ed that an AK-TV air kit be used with this appliance.
WARNING: IN A NEGATIVE
PRESSURE CONDITION (LIKELY
TO OCCUR IN NEW HOMES THAT
DO NOT HAVE ADEQUATE MAKE-UP
AIR) THE OUTSIDE AIR KIT MUST
BE INSTALLED TO OBTAIN
PROPER PERFORMANCE AND TO
HELP PREVENT SPILLAGE OF
COMBUSTION GASES.
!