Vermont Casting 2170 manual Care of the Catalytic Combustor, When to Suspect a Combustor Problem

Dutchwest Seneca

Adjusting Bolt

Front of

Stove

Lock Nut

Anchor Bolt

Damper Rod

ST441

Fig. 32 Damper adjustment.

Care of the Catalytic Combustor

This wood heater contains a catalytic combustor, which needs regular inspection and periodic replacement for proper operation. Reminder: It is against the law in the United States to operate this wood heater in a manner inconsistent with operating instructions in this manual, or if the catalytic element is deactivated or removed.

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 determine when it needs to be replaced. A non-func- tioning combustor will result in a loss of heating effi- ciency, and an increase in creosote and emissions.

The combustor should be visually inspected Òin placeÓ for fly ash accumulation and physical damage three times per year. Actual removal of the combustor is not recommended unless a more detailed inspection is warranted because of diminished performance as outlined below.

The refractory package that housed the catalytic combustor should be inspected annually for a buildup of fly ash and cleaned if necessary. This may be done during examination of the catalytic combustor.

When to Suspect a Combustor Problem

•With a fire in the stove and damper closed to activate the combustor, go outside and observe the smoke leaving the chimney.

•Then, open the stove damper and once again observe the smoke leaving the chimney.

Significantly more smoke should be observed after the second step when the stove damper is open and exhaust is not routed through the combustor. Be careful not to confuse smoke with steam from wet wood, however!

If either of these tests indicates a problem, consider other possible factors as well.

Assess your present operating conditions. In spring or fall, draft is weaker than it is in colder winter weather, and a related change in stove performance may result. Small hot fires are a good solution to sluggish perfor- mance under these conditions.

Burning ÒgreenÓ (insufficiently seasoned) wood will result in poorer performance than when burning prop- erly seasoned fuel. You may have to run your stove hotter (more air) to achieve good performance if you are burning green or wet wood. Also, any changes in operating routine should be considered at this time as a possible reason for changed performance.

Once you have ruled out any other possible causes for a decline in performance, you may proceed with an inspection of the catalyst.

Remove and Inspect the Combustor

Before you begin, observe the basic safety precautions for working with dusty materials: always wear safety glasses, a dust mask and gloves.

•Remove the stove top plate. It is held in place by two bolts. One bolt is accessible when you open the front door and look upward toward the underside of the top plate. The other bolt is most easily reached through the side loading door. Remove the two bolts.

•Lift the top plate off the stove. It is heavy, and you may choose to have a helper assist you.

•The combustor is located beneath the removable refractory package, directly below the stove top near the center of the stove.

There are two ways to evaluate the performance of your stoveÕs combustor. The first is to monitor the temperatures recorded on the probe thermometer. A properly functioning combustor should operate regularly in the range of 800-1200°F (430-650°C). Combustor temperatures consistently less than 800°F (430°C) are a sign that examination of the combustor is advisable.

The second performance test is to observe the amount of smoke leaving the chimney - both when the combus- tor has achieved Òlight-offÓ and when it has not. Follow

Combustor

ST746

Refractory

this simple two-step procedure: 24

Fig. 33 A cutaway view of the combustor and its refractory

cover.

2006063