34
Defiant
®
1975 Non-Catalytic / Catalytic Woodburning Stove
30005220
T
he catalytic element
This wood heater contains a catalytic combustor, which
needs periodic inspection and replacement for proper
operation. In the United States it is against the law to
operate this wood heater in a manner inconsistent with
the operating instructions in this manual.
Under normal operating conditions, the catalytic com-
bustor should remain active for two to six years (de-
pending on the amount of wood burned). However, it
is important to monitor the combustor periodically to
ensure that it is functioning properly, as well as to de-
termine when it needs to be replaced. A non-functioning
combustor will result in a loss of heating efficiency, and
an increase in creosote and emissions.
inspection and cleaning
Inspect the combustor for fly ash accumulation and
physical damage three times per year. Clean the com-
bustor as needed.
The refractory package that houses the catalytic
combustor should be inspected for a buildup of fly ash
and cleaned if necessary. This may be done when you
examine the combustor.
when to Suspect a combustor problem
The best way to evaluate the performance of your
Defiant’s combustor is to observe the amount of smoke
leaving the chimney — both when the combustor has
“lighted-off” and when it has not. Follow these steps:
•
With a fire going and the combustor properly activat-
ed, with the damper closed to route smoke through
it as described in the Operation Section, go outside
and observe the smoke leaving the chimney.
•
Then, open the stove damper and once again check
the smoke leaving the chimney.
You should see significantly more smoke when the
stove damper is open and exhaust does not pass
through the combustor. However, be careful not to
confuse smoke with steam from wet wood. Steam dis-
sipates in the air quickly; smoke does not.
If this test indicates a problem, consider other possible
factors as well, such as the weather or a change in the
quality of your fuel. In warm weather, draft is weaker
than it is in colder winter weather, and fires can burn
sluggishly. Small, hot fires are a good solution under
these conditions.
Burning “green” (insufficiently seasoned) wood will
result in poorer performance than burning properly
seasoned fuel. You may have to run your stove hotter
(more air) to achieve acceptable performance using
green or wet wood.
Also, consider any changes in your operating routine.
Once you have ruled out any other possible causes for
a decline in performance, inspect and clean the com-
bustor if necessary. Be sure to protect any surface you
use for setting the stove parts aside.
inspecting the combustor
Remove access door and inner fireback. Remove the
catalytic combustor by lifting and sliding it towards you.
(Fig. 48)
ST1180
catalyst access
Catalyst
Access Door
Inner Fireback
ST1180
Fig. 48
Inspect the catalytic combustor.
To assure a long life for the combustor, it is recom-
mended to service the combustor on a regular basis
based on the amount of use. This procedure takes
about five (5) minutes and requires no tools except for a
vacuum if cleaning is necessary.
cleaning the combustor
1. Check the combustor’s honeycomb-like element
for a buildup of fly ash. If any is evident, take the
combustor outside and clean it by blowing air gently
through it. Do not push anything through the honey-
comb; do not use compressed air to clear the pas-
sages. Such abrasion can scrape the thin coating of
platinum (the catalyst) off the ceramic base, shorten-
ing the catalyst’s life and reducing its effectiveness.
2. Inspect the element for damage or degradation.
Although small hairline cracks will not affect per-
formance, the element should be essentially intact.
If the element is broken in pieces or has sections
missing, it should be replaced. Call your local Ver-
mont Castings Authorized Dealer for a replacement
element.
