Lennox Hearth CR-3835R Ten Foot Rule Summary, Multiple Terminations, Special Offset Instructions

Models: CR-3835R

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Using a FTF8/10-CT1 Chase Termination:

Using a FTF8/10-CT2 Chase Termination: Less Than 10' TEN FOOT RULE SUMMARY

3'

Min

Figure 32

Using a FTF8/10-CT1 Chase Termination:

Refer to specific installation instructions in- cluded with FTF8/10-CT1 chase terminations for clearance and installation details.

Using a FTF8/10-CT2 Chase Termination:

Refer to specific installation instructions in- cluded with FTF8/10-CT2 chase terminations for clearance and installation details.

Note: It is recommended that all exterior ex- posed metal fireplace components; such as terminations, flashings, storm collars and/or flue be painted with a premium quality, high temperature, rust preventative paint designed for metal. This is especially important when installations are made in abnormally adverse or corrosive environments; such as near lakes, oceans or in areas with consistently high hu- midity conditions. Consult the paint manufac- turers instructions for proper preparation and application.

TEN FOOT RULE SUMMARY

The minimum chimney height above the roof and/or to adjacent walls and buildings is speci- fied by all major building codes.

If the horizontal distance from the peak of the roof is less then 10', the top of the chimney must be at least 2' above the peak of the roof.

If the horizontal distance from the chimney edge to the peak of the roof is more than 10' a chimney height reference point is established on the roof surface 10' horizontally from the chimney edge. The top of the chimney must be at least 2' above this reference point. In all cases, the chimney cannot be less then 3' above the roof at the edge of the chimney.

2' Min.

10'

3'

 

Min

The 2' in 10' rule is necessary in the interest of safety but does not ensure smoke-free opera- tion. Trees, buildings, adjoining roof lines, ad- verse wind conditions, etc., may require a taller chimney should the fireplace not draft properly (see Figure 32 ).

MULTIPLE TERMINATIONS

If more than one termination is located in the same chase or within the same general proxim- ity, we suggest they should be separated in distance at least 24" horizontally from flue cen- ter to flue center and stacked or staggered vertically at least 18" apart, from the termina- tion of one smoke exit to the termination of another smoke exit (Figure 33 ).

CTD

18"

18"

CTDT MULTIPLE TERMINATIONSFTF8 AND FTF10 CHIMNEY COMPONENT CALCULATIONSSPECIAL OFFSET INSTRUCTIONS CTDT

24"

24"

Figure 33

This suggestion is provided in the interest of better operation. If the terminations are located too close to each other, smoke may migrate from one flue into the other.

NOTE: DIAGRAMS & ILLUSTRATIONS NOT TO SCALE.

FTF8 AND FTF10 CHIMNEY COMPONENT CALCULATIONS

The minimum installed height of the completed fireplace systems is 15' 2" (4.67 m). The maxi- mum height for all systems is 50' 0" (15.24 m). To determine the number of chimney sections and chimney components required, follow these steps:

1.Determine total vertical height of the fire- place installation. This dimension is the dis- tance from the surface the fireplace sets on to the point where smoke exits from the termina- tion.

2.Determine the number of chimney compo- nents required, except chimney sections. This would include firestop spacers, stabilizers, roof flashing, etc.

3.The effective heights of the components are:

The Fireplace

=

39

¹⁄₂" (1003 mm)

FTF8/FTF10-12

=

10

¹⁄₄" (260 mm)

FTF8/F10-18

=

16

¹⁄₄" (413 mm)

FTF8/F10-36

=

34

¹⁄₄" (870 mm)

FTF8-48

=

46

¹⁄₄" (1175 mm)

CTD Termination

=

4" (102 mm)

CT1 Termination

=

12" to 18"

 

 

(305 mm to 457 mm)

CT2 Termination

=

15" to 23"

 

 

(381 mm to 584 mm)

SS Starter Section

=

19

¹⁄₄" (489 mm)

S4 Stabilizer *

=

3" (76 mm)*

*Required for every 30' (9.1 m) of vertical chimney and/or 10' of offset chimney.

4.Determine amount of chimney height re- quired by subtracting total combined height of all pre-selected components (fireplace and chimney components from total desired height.)

Reference Vertical Elevation Chart and deter- mine the number of chimney sections (quantity and length) required.

SPECIAL OFFSET INSTRUCTIONS

To clear any overhead obstructions, you may offset your chimney system using Security's 30° offset and return elbows. Use two elbows

an offset elbow to initiate the offset and a return elbow to terminate it.

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Lennox Hearth CR-3835R Ten Foot Rule Summary, Multiple Terminations, FTF8 AND FTF10 CHIMNEY COMPONENT CALCULATIONS