Vermont Casting 2478 manual Fireplace Installations, Floor Protection for Fireplace, 30002278

Models: 2478

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Fireplace Installations

Dutchwest Non-Catalytic Convection Heater

Procedure:

1. Convert specifications to R-value:

i. R-value given - no conversion needed.

ii. k-factor is given with a required thickness (T) in inches: R = 1kx T

iii. K-factor is given with a required thickness (T) in

inches: R = 1 x T K x 12

iv. r-factor is given with a required thickness (T) in inches: R = r x T

2. Determine the R-value of the proposed alternate floor protector:

i. Use the formula in Step 1 to convert values not expressed as R.

ii. For multiple layers, add R-values of each layer to determine overall R-value.

3. If the overall R-value of the system is greater than the R-value of the specified floor protector, the alter- nate is acceptable.

EXAMPLE: The specified floor protector should be 5/8- inch thick material with k-factor of 0.84. The proposed alternate is 4” brick with an r-factor of 0.2 over 1/8” mineral board with a k-factor of 0.29

Step a: Use formula above to convert specification to

R-value: R = 1k x T =0.841 x 0.625 = 0.744 Step b: Calculate R of proposed system.

4” brick of r = 0.2, therefore: Rbrick = 0.2 x 4 = 0.8

1/8” mineral board of k = 0.29, therefore 1

Rmineralboard = 0.29 x 0.125 = 0.431

Rtotal = Rbrick + Rmineralboard = 0.8 + 0.431 = 1.231

Step c: Compare proposed system Rtotal of 1.231 to specified R of 0.744. Since proposed system Rtotal is greater than required, the system is acceptable.

Definitions

R =

2

)(hr)(°F)

 

 

 

 

(ft

 

 

 

 

 

 

 

Btu

 

 

 

 

k =

 

(Btu)(in)

= K x 12

 

 

(ft2)(hr)(°F)

 

 

 

 

K =

 

(Btu)(ft)

 

 

 

 

 

 

(ft2)(hr)(°F)

 

 

 

 

 

 

(ft2)(hr)(°F)

 

1

 

 

r =

 

(Btu)(in) =

 

 

 

k

 

Fireplace Installations

The Dutchwest Model 2478 has a reversible flue collar to allow for either top exit or rear exit installations.

You may install your Dutchwest Model 2478 in an exist- ing fireplace as a fireplace insert with no legs, or with the standard legs attached.

To install the heater without legs as a fireplace insert, the floor must be completely noncombustible, such as an unpainted concrete floor over earth.

Many fireplaces do not satisfy the “completely non- combustible” requirement because the brick or con- crete hearth in front of the fireplace opening usually is supported by heavy wooden framing as in Figure 13. Because heat passes readily through brick or concrete, it can easily pass through to the wood. As a result, such fireplace hearths are considered a combustible floor. You may not install a heater on a combustible hearth without legs. Standard leg installations must include the bottom heat shield. The floor protector must also meet standard requirements for freestanding installations.

Floor Protection for Fireplace

Installations with Standard Legs

Fireplace installations with the standard legs and the bottom heat shield must have a floor protector of the same construction as that specified for freestanding installations: use an approved 5/8” (16mm) noncom- bustible hearth pad with K = 0.84 BTU/in ft2 hr °F or an equivalent material with an R-value of at least 0.744 (that may be covered with a decorative noncombustible material if you desire). (Refer to “How to Determine if Alternate Floor Protection Materials are Acceptable” section) The floor protector must extend at least 16” (406 mm) [18” / 457 mm in Canada] from the front of the stove and from the left (loading door) side, and at least 8” (203 mm) from the right side and rear. It must also provide protection beneath any horizontal runs of the chimney connector, including 2” to either side.

Many raised hearths will extend less than the required distance from the front of the heater when it is installed. In such cases, sufficient floor protection, as described above, must be added to extend the hearth 16” (406 mm) [18” (457 mm) in Canada].

Hearth rugs do not satisfy the requirements for floor protection.

Fireplace insert installations also have specific clear- ance requirements to the side walls, side decorative trim, and fireplace mantel. This information is found in “Fireplace Installation Clearances” in this section.

REMINDER- FIREPLACE INSERT INSTALLATIONS WITHOUT LEGS ARE PERMISSIBLE ONLY IF THE HEARTH IS COMPLETELY NONCOMBUSTIBLE, SUCH AS UNPAINTED CONCRETE OVER EARTH.

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30002278

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Vermont Casting 2478 Fireplace Installations, Floor Protection for Fireplace, Installations with Standard Legs, 30002278