Hearth and Home Technologies BIR50-B Arch / Mailbox Style Shroud, Pyramid Style Shroud

C. Arch / Mailbox Style Shroud

The arch or mailbox style shroud generally has two solid sides and a solid top. The exhaust openings are on the two open ends of the arch (Figure 10.3). Table 10.2 lists the minimum shroud dimensions, the minimum open area per side, and the minimum total open area for the shroud.

Table 10.2

Arch / Mailbox Style Shroud Minimum Dimensions

Chimney										Min Open Area	Min Total Open
Diameter		Chimney Area		Min Height H		Min Length L		Min Width W		per side	Area
in	mm	in	mm	in	mm	in	mm	in	mm	sq in	sq in
14	355.6	154	3911.6	24	609.6	32	812.8	32	812.8	520	1040

H: Minimum height of shroud

L: Minimum length of shroud

W: Minimum width of shroud

H

		Shaded area represents screened open area. Actual
W	L	shape of shroud may vary as long as minimum dimen-
		sions and minimum open area requirements are met.

Figure 10.3 Arch/Mailbox-Style Shroud Minimum Dimensions

D. Pyramid Style Shroud

The pyramid style shroud is roughly square or rectangular with an open top for exhaust as well as openings along the base of the four sides (Figure 10.4). Table 10.3 lists the minimum shroud dimensions, including the minimum height and length of the base opening.

Table 10.3

Pyramid Style Shroud Minimum Dimensions

Chimney
Diameter		Min Height H1		Min Length L		Min Width W		Min Base B		Min Height H2
in	mm	in	mm	in	mm	in	mm	in	mm	in	mm
14	355.6	24	609.6	32	812.8	32	812.8	22	558.8	2	50.8

L: Minimum length of shroud top opening

W: Minimum width of shroud top opening

H1: Minimum total height of shroud

B: Minimum length of opening along base

H2: Minimum height of opening along base

WL

H1

	H2	Shaded area represents screened open area. Actual
		shape of shroud may vary as long as minimum dimen-
B		sions and minimum open area requirements are met.

Figure 10.4 Pyramid-Style Shroud Minimum Dimensions

Heatilator • Birmingham BIR50-B • 4059-682C• 8/12 35