SECTION 4: CLEARANCES TO COMBUSTIBLES
SECTION 4: CLEARANCES TO COMBUSTIBLES 4.1 Required Clearances To Combustibles
WARNING
Fire Hazard
Keep all flammable objects, liquids and vapors the required clearances to combustibles away from heater.
Some objects can catch fire or explode when placed close to heater.
Failure to follow these instructions can result in death, injury or property damage.
Clearances are the required distances that
combustible objects must be away from the heater to prevent serious fire hazards. Combustibles are materials that catch on fire and include common items such as wood, paper, rubber, fabric, etc. Maintain clearances to combustibles at all times for safety.
Clearances for all heater models are located on the serial plate of the heater and throughout the manual. Check the clearances on the serial plate to make sure the product is suitable for your application and the clearances are maintained. Read and follow the safety guidelines below:
•Keep gasoline or other combustible material including flammable objects, liquids, dust or vapors away from this heater or any other appliance.
•The stated clearances to combustibles represents a surface temperature of 90° F (50° C) above room temperature. Building materials with a low heat tolerance (such as plastics, vinyl siding, canvas,
•Consult local Fire Marshal, Fire Insurance Carrier or other authorities for approval of proposed installation when there is a possibility of exposure to combustible airborne materials or vapors.
4.2 Clearances To Combustibles
Clearances must be as indicated on Page 7, Figure 4. If clearances to combustibles are not indicated, then installation clearances apply.
Figure 4: Installation Clearances and Clearances to Combustibles
Installation Clearances
Clearances to Combustibles
Wall
Terminal
Roof Terminal
24" for 
adequate 
air flow access axial fan.
(Optional separated
combustion concentric
venting shown.)
Top
10' 
(3 m)
6" 
(15 cm)
6"
(15 cm)
31"** 
(79 cm)
3"
20' (6.0 m) - 30' (9.1 m) Max. Mounting Height*
(8 cm)
* Recommended mounting height varies with heater input. | Clearance to Vent: 2" (5 cm) |
Heaters may be mounted at a higher level if destratification |
|
fans are installed. | **31" (79 cm) minimum is necessary |
Note: Venting directly from top of heater not applicable | for servicing. |
on Models 150 - 400.
The heater must always be installed at least 6' (2 m) above the floor. The vent pipe must have clearance from combustibles by 2" (5 cm).
If installed at low levels where individuals can come in contact with hot heat exchanger components, adequate guarding must be provided.
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