Important Installation Instructions for Mason or Builder
These instructions are written to be used by an experienced mason or builder who is familiar with applicable codes concerning the
construction of masonry fireplaces.
Step 1:
Finish the foundation with a layer of firebrick upon which to set the Circulator Unit. The firebrick should
extend beyond the Circulator at the sides and back and be at least flush with the front of the Circulator. If the
fireplace is to have an ash pit, the ash dump should be put in at the time of the firebrick base is laid. Do not lay
firebrick up into the metal firebox of the Circulator. (See Figure 1.)
Fig 1: Hearth Plan at
Floor Level
Step 2:
Position the Circulator on the firebrick hearth. Unpack glass wool insulation and apply around the bottom
of the unit. Cover the unit with a single thickness of insulation, taking particular care at corners. A thin watery
mixture of mortar brushed on the steel Circulator will help to hold the insulation in place. At this point if
particular care is given to the glass wool insulation, location of the cold air intake grille, and gauging of the
masonry work, the rest of the installation will be made much easier. (See Figure 2.)
Fig 2: Unit in Position
Fig 3: Insulation & Concealed
Joint
Step 3:
Lay the first course of masonry dry around the unit to check dimensions, thickness of mortar joints
and grille locations. Take care to prevent the masonry from touching the unit at any point. The finished width
of the fireplace opening should be 1” to 2” less than the width of the Circulator opening. Lay the masonry
beyond the Circulator on each side of the Circulator opening, making a concealed joint between the Circulator
and the masonry. Due to heat expansion, mortar will not stay in this concealed joint. (See Figure 3.)
Step 4:
Plan the location of the cold air intake grilles. Air must not pass direct from the cold air inlet to the hot air
outlet. The air must be circulated through the unit. Air passages should be finished smoothly to speed air flow
and prevent heat loss.
Fig 4: Brick Work & Grille
Location
The “Vestalaire Universal Grille and Duct” system will simplify planning and installation of air intakes and outlets.
If electric fan grilles are to be used in the Circulator, and the power line to the fan is concealed, it may be
desirable to locate the conduit and junction box in the masonry. When fans are used, two fans–one located in
each cold air intake–are needed. Never locate the fans in the warm air outlet. Set the cold air intake grilles in
place. Do not remove top grille face until the boxes are installed in the masonry. This assures a neat and level
