Lennox Hearth CR-3835R Chimney Height, Chase Enclosure, Assembly Outline, Before You Start

4

Insulate Joists

Same As Ceiling

Draft Stops

Firestop

CTDT

Termination

Note: Non-

Combustible

Chase

Flashing

Must Be

Used To

Cover

Chase

Opening

Optional

Insulation

In Outside

Walls Of

Chase

8'

Level

Solid

Continuous

Surface

	Outside
Insulation	Base
(Thermal Barrier)

Figure 2

WARNING: IF INSULATION IS USED, THE FIREPLACE MUST NOT BE PLACED DI- RECTLY AGAINST IT. INSULATION OR VAPOR BARRIERS, IF USED, MUST FIRST BE COVERED WITH GYPSUM BOARD, PLYWOOD, PARTICLE BOARD OR OTHER MATERIAL TO ASSURE INSULATION AND VAPOR BARRIERS REMAIN IN PLACE.

WARNING: DO NOT PACK OR FILL RE- QUIRED AIR SPACES WITH INSULATION OR OTHER MATERIAL. NO MATERIAL IS ALLOWED IN THESE AREAS.

Note: Do not insulate the chase cavity with blown or fill type insulation materials.

Note: Local codes may not require firestopping at the ceiling levels for outside chase installa- tions. However, it is recommended for safety and the reduction of heat loss.

Chimney Height

The total height of your completed fireplace sys- tem from the surface the fireplace rests on to the chimney top must not exceed 50' (15.24 m) and must also meet minimum height requirements. Refer to the minimum system height chart.

Minimum System Height

	FTF10	FTF8
Vertical	15'2"	16'8"
Installation	(4.62 m)	(5.08 m)
One	15'2"	16'8"
Offset	(4.62 m)	(5.08 m)
Two	25'0"	25'0"
Offsets	(7.62 m)	(7.62 m)

Chase Enclosure

A chase is a vertical box-like structure con- structed to surround the fireplace and chimney. Refer to Figure 2 for a typical chase configura- tion. As with all chimney installations, avoid overhead obstructions such as trees, power lines, etc. A chase should be constructed and insulated just like any outside wall. In a cold climate, we recommend the base of the chase should also be insulated between the solid continuous floor beneath the fireplace and the chase bottom. Chase insulation in a cold cli- mate installation is not required for safety.

ASSEMBLY OUTLINE

Before You Start

Check your inventory list to be sure you have all the necessary parts supplied in good usable condition. Check also for any concealed damage.

Check the operation of the damper. The damper is controlled through the use of a control lever located within the firebox opening at the top center just behind the firebox lintel (Figure 3 ). The control lever snaps into place at the ex- treme range of motion, up and back in the closed position. When pulled forward and down, the damper is open.

Damper	Damper
Closed	Open
Lintel
	Combustion
	Air Actuator

Figure 3

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

LOCATION OF FIREPLACE

Carefully select the proper location for heat circulation, aesthetics, chimney obstructions and clearance to side wall(s). With proper pre- planning, a slight adjustment of a few inches can save considerable time and expense later during construction and assembly.

Inside
Corner
Installation	Hearth
	8" (203mm) Min.
	To Protected Side
	Wall
Hearth
	Outside
	Corner
	Installation

Figure 4

Carefully consider the position of the fireplace opening with respect to the location of adja- cent or nearby stairwells, bath or kitchen ex- haust fans and/or return air registers for forced air furnaces/air conditioners that could cause a smoking fireplace condition if the house is tightly insulated.

When locating the fireplace, consideration must be given to combustibles and final finishing. See Figure 5 and confine the final location of combustible finish materials to the "Safe Zone".

DO NOT permanently place furniture or other items such as decorative pillows within 60" of the fireplace front face.

Combustible
Materials
Allowed In			Fireplace
Shaded Area
“Safe Zone”	11	⁷⁄₈”
			8"
		45°
15 ⁷⁄₈”			Min. Distance To
		8"
			Protected Side Wall
	12"		Min. Distance To
			Unprotected Side Wall

Figure 5