Exhaust Blower Ratings - GE JP989 Owner's Manual & Installation Instructions

Installation Instructions

EXHAUST BLOWER RATINGS

Exhaust Blower Safety Warning
Sufficient air is needed for proper combustion and exhausting of gases through the flue
(chimney) of other fuel burning equipment to prevent back drafting. Follow the heating
equipment manufacturer's guidelines and safety standards such as those published by the
National Fire Protection Association (NFPA), the American Society for Heating, Refrigeration
and Air Conditioning Engineers (ASHRAE) and local code authorities.
NOTE: The exhaust blower output is approximately 400 CFM (cubic feet per minute) without
ductwork. Each installation is different and ductwork affects blower output accordingly. Actual
blower exhaust CFM can be approximated using the graph below.
Step 1: Calculate the "equivalent duct length" using the "DUCTWORK CALCULATIONS" table
in these instructions for your installation.
Step 2: Find the approximate intersection point of the blower exhaust performance curve with
the equivalent duct length to estimate the actual maximum blower output for your
installation.
Examples: 50 equivalent feet of ductwork has approximately 320 CFM.
100 equivalent feet of ductwork has approximately 265 CFM.
450
400
350
300
250
200
150
100
50
0
0 25
Downdraft Cooktop Exhaust Blower CFM
50 75
6" Diameter Equivalent Duct Length
19
100 125 150