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Please read these instructions before beginning
Step by step checklist
1.
Check the chimney for cracks, cavities and blockages and
repair these. The size of the Jetmaster Firebox is determined
by the minimum dimensions of the chimney flue. Minimum
flues areas are:
Model 500, 600, 700sh- 400 cm2
Model 700D, 850-450 cm2
Ensure that this area is maintained throughout the entire
chimney. Flues that are 10% smaller than this will work
depending on the height of the chimney. Chimney pots that
are too small should be removed. Conduct a smoke test prior
to a Jetmaster install to ensure the chimney properly draws.
If the chimney does not draw, do not proceed with the
installation. Further repairs may be required.
2.
Measure the width, depth height of the recess. The
following table lists the minimum dimensions of the recess
for each unit.
• Allow 25mm on each side of the firebox for insulation
A.
If recess is too large:
The recess can be reduced by inserting bricks or Hebel at
the sides and/or back, and where necessary between the
top of the unit and the underside of the lintel. The
existing hearth can also be built up either with bricks or
by forming a plinth.
Use Jetmaster fascias and trims to seals gaps less than
75mm between sides and top of the unit and masonry.
B.
If recess is too small:
The recess can be made deeper by removing the rollback
and smoke shelf. If the height is too low, remove the
lintel and replace at the required height.
If the sides have to be removed it is suggested an
experienced builder to do the work as the sides support
inner flues of the chimney.
NOTE: Allow 1-5mm expansion gap for all materials.
3.
Repair any cracks or cavities in the recess especially if it
has been chopped out to accommodate a specified unit size,
and the cavity between a double brick wall has been
exposed.
Note: No metal gather or flue is required if the chimney passes a
smoke test.
4.
Tape the insulation to back and sides of the Jetmaster
and slide into position, taking care not to snag the fibreglass
insulation against the sides.
Note:
A. Do not recess the unit by more than 110mm.
B. The two smoke outlets on the firebox marry up with the
existing chimney. (There must be a 200mm minimum to any
overhang above smoke outlets).
C. Do not obstruct air intake at the bottom of the unit.
5.
Use foil tape and cardboard to temporarily seal outer
edges of the unit to the chimney face then have a test fire
using a mixture of dry and damp paper to create a smokey
fire.
If continuous smoke spillage occurs, check the size of the
chimney pots and the chimney for blockages.
“Downdraught” (wind blowing down the chimney) is
recognised by occasional puffs of smoke. In this case use a
Jetmaster rotating cowl or a high wind cowl.
6.
Seal unit into position with the masonry, fascias or trims,
ensuring any air leak around frame is limited. Allow masonry
work to cure for a minimum of three days.
See next page for diagrams.
UNIT SIZE
WIDTH
DEPTH
HEIGHT
500
570
350
640
600
670
350
640
600 LOW
670
350
590
700SH
770
350
640
700 LOW
770
350
590
700D
770
400
690
850
920
450
740
850 LOW
920
450
690
1050
1100
500
790
1050 LOW
1100
500
690
6. Existing brick chimney installation
