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INSTALLATION OF A FIREPLACE BLOCK-OFF PLATE
A block-off plate is used to prevent the exhaust going into a masonry fireplace from entering the inside of
the house. It ensures a tight seal between the masonry fireplace and the stove pipe leading through it. A
properly made block-off plate, coupled with either a positive or direct connection, provides the wood
heating appliance with a vacuum draw that pulls the flue gases out of the appliance and out the top of the
chimney. The directions below show how a block-off plate is made.
1.
Measure below damper area the width from side to side at rear of smoke chamber. Label this
Measurement "A".
2.
Measure the width below damper area from side to side at front of smoke chamber. Label this
Measurement "B".
3.
Measure the depth below damper front to back of smoke chamber. Label this Measurement "C".
4.
Make a template of your measurements, but add 2" to each of the sides.
CROSS SECTION OF FIREPLACE
B
C
A
Your template should resemble the drawing on the next page with the dotted lines indicating your initial
measurements and the solid line indicating the additional 2". You will use this template to cut a piece of
sheet metal (minimum 24 gauge) to install in your smoke chamber.
The solid line will represent the shape of the piece of sheet metal cut while the dotted line will represent
where you will bend the sheet metal for installation. Mark the position of several holes on each side to
suit your specific installation, and drill 1/4" diameter holes.
Summary of Contents for 996 Extended
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