Hearthstone Quality Home Heating Products, Inc
® Green Mountain 40 (Model 8640)
26
Figure 21 - REMOVING RISER AND REAR STONES
9. Only remove the catalysts if required. In
general, the less you handle the catalysts,
the better. If any unusual conditions are
found, remove the catalyst blocks – See
replacing the catalysts.
10. Some warping or bowing of the catalysts over
time is acceptable, as long as the catalyst
gasket continues to seal. Measure the
catalysts in the middle section – if the
dimensions are outside the range shown in
Figure 20 on the next page, replace the
catalysts.
11. Re-install Interam gasket material on the
catalysts. Masking tape can be used to hold
the gasket in place on the catalysts. It will
burn away when the stove gets hot. Wrap
the tape around the gasket and catalysts so it
is reasonably tight and some of the tape side
is hanging over the edge of the catalysts, all
around. Fold the edges of the tape in over the
catalyst’s face. Finally add 3 smaller strips of
tape as shown to hold gasket snug at ends
and in the middle. This will reduce snagging
and make it easier to reinstall the catalysts.
12. Once the gasket is installed on the catalysts,
gently push the catalysts into the catalyst
opening until the catalysts hit against the
back wall of the cavity. Take care to ensure
the gasket is not damaged.
13. Replace the catalyst access door.
14. Heat the stove slowly during your next fire to
allow the Interam gasket to fully expand and
seal the catalysts.
R
EPLACING THE REFRACTORY STONE AND
SECONDARY RISER ASSEMBLY
1. Allow the stove and ashes to fully cool.
2. Open the front door of the stove and fully
clean any ash in the firebox
3. Remove the baffle following the instructions
in “Inspecting the Catalysts and
Removing/Replacing the baffle.
4. Remove the side stones one at a time by
tipping them towards the inside of the
firebox from the top.
5. With side stones and baffle removed, the
secondary riser assembly and rear stones
can be lifted up and out of the stove.
6. Installation is the reverse of disassembly.
Make sure that the secondary riser tube is
seated in the pocket at the rear of the
bottom casting.
Figure 20 - Acceptable Catalytic Distortion