Vermont Casting 1910, 0968 installation instructions Remove the bricks and the brick retainer

Vermont Castings Defiant

Alignment Notches	Right Wedge
Left Wedge
Brick Guide
Brick Clip
Bricks
ST556
Fig. 37 Remove the bricks and the brick retainer.

Lower Fireback		ST557
Fig. 38	Remove the lower fireback.

3.Carefully remove the catalytic combustor’s refractory access cover, then remove the combustor. The refractory material is brittle; handle it carefully. (Fig. 39)

4.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 passages. Such abrasion can scrape the thin coating of platinum (the catalyst) off the ceramic base, shortening the catalyst's life and reducing its effectiveness.

	Catalytic
	Element
	Catalytic Access
ST558	Panel
Fig. 39	Remove and inspect the catalytic element.

5.Inspect the element for damage or degradation. Although small hairline cracks will not affect perfor- mance, the element should be essentially intact. If the element is broken in pieces or has sections missing, it should be replaced. Call your local Vermont CastingsMajestic Products Company Authorized Dealer for a replacement element.

While the catalytic element is removed, check the condition of the secondary air probe. Use an inspection mirror to locate the probe within the combustion chamber. (Fig. 40) The probe should extend 1” to 1¹⁄₂” into the chamber and show no signs of excessive deterioration, such as warping, corrosion, or short length. A damaged secondary air probe can affect catalytic performance. If the probe needs replacement, contact your local dealer.

1"

ST559

Fig. 40 Use an inspection mirror to check the reflected view of the secondary probe.

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