Hearth and Home Technologies CD4842MLR, CD4842MR Construct the Appliance Chase, Clearances

B. Construct the Appliance Chase

A chase is a vertical box-like structure built to enclose the gas appliance and/or its vent system. In cooler climates the vent should enclosed inside the chase.

NOTICE: Treatment of ceiling firestops and wall shield firestops and construction of the chase may vary with the type of building. These instructions are not substitutes for the requirements of local building codes. Therefore, you MUST check local building codes to determine the requirements to these steps.

Chases should be constructed in the manner of all out- side walls of the home to prevent cold air drafting prob- lems. The chase should not break the outside building envelope in any manner.

Walls, ceiling, base plate and cantilever floor of the chase should be insulated. Vapor and air infiltration barriers should be installed in the chase as per regional codes for the rest of the home. Additionally, in regions where cold air infiltration may be an issue, the inside surfaces may be sheetrocked and taped for maximum air tightness.

To further prevent drafts, the wall shield and ceiling fire- stops should be caulked with high temperature caulk to seal gaps. Gas line holes and other openings should be caulked with high temp caulk or stuffed with unfaced insu- lation. If the appliance is being installed on a cement slab, a layer of plywood may be placed underneath to prevent conducting cold up into the room.

C. Clearances

NOTICE: Install appliance on hard metal or wood surfaces extending full width and depth. DO NOT install directly on carpeting, vinyl, tile or any combustible material other than wood.

WARNING! Risk of Fire! Maintain specified air space clearances to appliance and vent pipe:

•Insulation and other materials must be secured to prevent accidental contact.

•Failure to maintain airspace may cause overheating and a fire.

1/2 in. (13 mm)

1/2 in. (13 mm)

Drywall

0 in.

Combustible flooring may be installed next to the front of the appliance.

30in.

(762 mm)

to ceiling	0 in. to level
	of standoffs

D

B

C

A

Object	36 in.
Combustible	(914 mm)

Figure 5.2 Clearances to Combustibles

0 in. to floor

Note: Adjust framing dimensions for interior sheathing (such as sheetrock)

		A	B	C	D	D
		Rough	Rough	Rough	Rough	Rough
		Opening	Opening	Opening	Opening	Opening
Model		(Width)	(Height)	(Depth)	(DVP Pipe)	(SLP Pipe)
CD4236M	in.	42	39	23	10	9
	mm	1067	984	584	254	229
CD4842M	in.	48	39	23	10	9
	mm	1219	984	584	254	229

18 Heatilator • Caliber Mesh CD Series-SIT Valve • 4040-849 Rev J • 06/08