Benjamin Heating products WK400, Owner'S Manual

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NOTE:
Maximum fan limit setting 240 degrees F. DO NOT set flue draft above 0.05" W.C. If the furnace
is installed in a tight (air sealed) basement or furnace room, adequate air must be supplied for
combustion and ventilation, or the furnace will NOT work properly.
Use only metal ducts for this furnace.
COMBUSTION AIR
To achieve satisfactory combustion, an adequate supply of fresh air is required. In confined areas, a grilled
opening should be provided. The minimum total area of opening is 1 square foot per 100,000 BTU/HR
(total the combined maximum BTU’s of the two furnaces), for a WK400A ADD-ON. Where fans are used
in the fuel storage area, they should be installed so as not to create negative pressures in the room where
the furnace is installed.
FIREBOX
The firebox must be filled and maintained with sand or ash to 1-1/2" below fire door sill. This is to ensure
proper air flow thru the fire.
MINIMUM CLEARANCES
The furnace must be installed on a non-combustible floor.
Minimum clearances from combustible material are as follows:
Front: 48" Sides: 18"
Rear: 24" Smoke Pipe: 18"
Top of Plenum and first 6' of duct: 6", then 2"
CLEARANCES MUST BE MAINTAINED