Monessen Hearth NB18, NB24 operating instructions Fireplace And Hearth Dimensions

FIREPLACE AND HEARTH DIMENSIONS

WARNING

This appliance is for installation only in a solid-fuel burning masonry or UL127 factory- built fireplace, vent free appliance, or in listed ventless firebox enclosure. It has been design certified for these installations.

Exception: DO NOT install this appliance in a factory-built fireplace that includes instructions stating it has not been tested or should not be used with unvented gas logs.

Use manufacturer's installation and clearance requirements as defined in their manual.

The NB Series unvented room heater is approved for installation into the following unvented fireplaces:

GCUF Series Fireboxes Magnum36/42, Lo-Rider36 or BUF

The NB Series unvented room heater may also be installed into a Ventless Firebox Enclosure for Gas Fired Decorative Type Unvented Room Heaters per IAS Requirement No. 2-97 ANSI Z21.91-2001 (typically referred to as a "Universal Firebox"), as long as firebox hearth dimensions meet the minimum hearth dimensions shown below.

Model	A	B	C	D
NB18 with BO18(R,F)	26"	13"	18"	17"
NB24 with BO24(R,F)	29"	13"	221/4"	17"
NB24 with BO30(R,F)	33"	13"	251/4"	17"

Without front grate installed “B” will be 121/2.

C

D

A

B

Figure 2 - Hearth Minimum Dimension

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