Waterford Appliances LEPRECHAUN 90 O.S.A operating instructions Thimbles, Figure B, Figure C

THIMBLES

Thimbles for chimneys or vent connectors should be of fire clay (ASTM C 315, specifications for Clay Flue Linings), galvanised steel of minimum thick- ness of 24 gauge, or material of equivalent durabili- ty. Thimbles should be installed without damage at the liner. The thimble should extend through the wall to, but not beyond, the inner face of the liner and should be firmly cemented to masonry.

Thimbles should be located to provide adequate pitch or rise of chimney or vent connectors and, where the ceiling above the appliance is constructed of combustible material, the location of the thimble should provide minimum clearance required for the connector as specified in section under Minimum Clearances.

Insulation material used as part of wall pass-through system should be of non-combustible material and should have a thermal conductivity of 1.0 Btu. in./ft.F (4.88 kg.cal/hr.m.c) or less. All clearances and thick- nesses are minimums; larger clearances and thick- nesses are acceptable. Any material used to close up the opening for the connector should be of non- combustible material. A connector to a masonry chimney, except for System 2 (under heading Chimney Connector System, Thimbles and Clearances), shall extend to piece through the wall pass-through system and the chimney wall to the inner face of the flue liner, but not beyond.

CHIMNEY CONNECTOR SYSTEMS, THIMBLES, AND CLEARANCES FROM COMBUSTIBLE WALLS

1.Minimum 3 1/2” (90mm) thick brick masonry wall framed into combustible wall with a min. of 12” (305mm) brick separation from clay liner to combustibles. Fire clay liner (ASTM C315 or equivalent) min. 5/8” (16mm) wall thickness, should run from outer surface of brick wall to, but not beyond, the inner sur- face of chimney flue liner and should be firmly cemented in place.

Minimum chimney clearance to brick and combustibles 2” (50mm)

Minimum clearance 12” (300mm) of brick

Fire Clay Liner

Chimney connector

Minimum 12” (300mm) to combustibles

Masonry

Chimney

FIGURE A constructed to

NFPA 211

2.Solid insulated listed factory-built chimney length of the same inside diameter as the chimney connector and having 1” (25mm) or more of insulation with a min. 9” (230mm) air space between the outer wall of the chimney length and combustibles. The inner end of the chimney length shall be flush with the inside of the masonry chimney flue and shall be sealed to the flue and to the brick mason- ry penetration with non water-soluble refrac- tory cement. Supports should be securely fastened to wall supports and the chimney

length shall not penetrate the chimney liner.

Minimum chimney clearance from masonry to sheet steel supports and combustibles 2” (50mm)

(230mm)
	Non-soluable
	refractory
	cement
	Chimney
	length flush
	with inside
	of flue

Masonry chimney constructed to NFPA 211

Factory built chimney length

Air space 9” (230mm) minimum

FIGURE B

3.Sheet steel chimney connector, min. 24 gauge in thickness, with a ventilated thimble, min. 24 gauge in thickness, having two 1” (25mm) air channels, separated from com- bustibles by a min. of 6” (150mm) of glass fibre insulation. Opening should be covered and thimble supported with a sheet steel support, min. 24 gauge in thickness. Supports should be securely fastened to wall surfaces on all sides and should be sized to fit and hold chimney section. Fasteners used to secure chimney sections should not penetrate chimney flue liner.

Minimum chimney clearance to sheet steel supports and combustibles 2” (50mm)

Two air channels each 1” (25mm)

Chimney connector

Minimum 6” (150mm) glass fibre insulation

Sheet steel	Two ventilated air
supports
	channels each 1”
	(25mm) constructed
	of sheet steel

FIGURE C

4.Solid insulated listed factory-built chimney length with an inside diameter 2” (50mm) larger than the chimney connector and hav- ing 1” (25mm) or more of insulation, serving as a pass-through for a single wall sheet steel chimney connector of min. 24 gauge thickness, with a min. 2” (50mm) air space

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