Downdraft Ventilators | McMaster-Carr

	Voltage Voltage

120V AC

208 to 230V AC

460V AC

	Base Width Base Width

	Blade Diameter Blade Diameter

	Airflow @ Static Pressure Airflow @ Static Pressure

	Power Power

	Electrical Phase Electrical Phase

Single

Three

	Drive Type Drive Type

Direct

Belt

	Motor Speed Motor Speed

	Motor Enclosure Type Motor Enclosure Type

Totally Enclosed

Open Dripproof (ODP)

	Overall Diameter Overall Diameter

	Current Current

	Volume Volume

	DFARS (Defense Acquisition Regulations Supplement) DFARS (Defense Acquisition Regulations Supplement)

DFARS Specialty Metals
COTS-Exempt

	Overall Height Overall Height

	Weight Weight

	REACH (Registration, Evaluation, Authorization and Restriction of Chemicals) REACH (Registration, Evaluation, Authorization and Restriction of Chemicals)

REACH Compliant

	RoHS (Restriction of Hazardous Substances) RoHS (Restriction of Hazardous Substances)

RoHS Compliant

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16 Products

About Exhaust Fans

About Sound Levels

Measured in decibels (dB), volume ratings indicate how much noise equipment makes. Some common volume levels include a whisper @ 20 dB, a refrigerator @ 40 dB, a conversation @ 60 dB, and a light machine shop @ 90 dB. OSHA recommends hearing protection for exposure to 80 dB and greater.

Direct-Drive Downdraft Roof-Mount Exhaust Fans

Direct-drive fans have fewer moving parts than belt-drive fans for less maintenance. More economical than upblast roof-mount exhaust fans, these draw stagnant and humid air out through your roof and then direct it back toward the roof. All fans have a disconnect switch to turn off the power for servicing.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

For technical drawings and 3-D models, click on a part number.

Fans
						Overall									Mounting Bases
	Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Wt., lbs.	Max. Ambient Temperature	Housing Material	Specifications Met		Each		Each
Totally Enclosed Motor Enclosure
120V AC, Single Phase—Hardwire
1	10"	60 cfm @ 1/2 in. of H₂O 500 cfm @ 0 in. of H₂O	Not Rated	1,500	1/30	18 5/16"	11 1/4"	19"	21	Not Rated	Aluminum	ETL Listed	0000000	0000000	0000000	0000000
1	12"	430 cfm @ 1/2 in. of H₂O 830 cfm @ 0 in. of H₂O	Not Rated	1,500	1/10	20 5/16"	11 3/4"	19"	30	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
1	14"	520 cfm @ 1/2 in. of H₂O 1,100 cfm @ 0 in. of H₂O	Not Rated	1,100	1/6	27 5/16"	14 5/8"	21"	39	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
1	18"	1,200 cfm @ 1/2 in. of H₂O 2,400 cfm @ 0 in. of H₂O	Not Rated	1,100	1/3	33 9/16"	16 3/8"	26"	60	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
Open Dripproof Motor Enclosure
120V AC, Single Phase—Hardwire
2	11"	600 cfm @ 1/2 in. of H₂O 800 cfm @ 0 in. of H₂O	57 dBA @ 5 ft.	1,625	3/16	23 3/4"	16 1/4"	19"	37	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
2	12"	950 cfm @ 1/2 in. of H₂O 1,250 cfm @ 0 in. of H₂O	62 dBA @ 5 ft.	1,625	1/4	26 1/4"	19 1/8"	21"	53	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000
2	14"	2,100 cfm @ 0 in. of H₂O 1,800 cfm @ 1/2 in. of H₂O	66 dBA @ 5 ft.	1,625	1/2	29 3/4"	21 3/4"	21"	56	Not Rated	Aluminum	ETL Listed	0000000	000000	0000000	000000

Belt-Drive Downdraft Roof-Mount Exhaust Fans

Belt-drive fans are quieter and have a longer life span than direct-drive fans because components can be replaced if worn or damaged. More economical than upblast roof-mount exhaust fans, these draw stagnant and humid air out through your roof and then direct it back toward the roof.

Note: Airflow depends on the resistance created by ductwork. This resistance, known as static pressure (SP), is measured in inches of water.

Fans
					Overall						Mounting Bases
Blade Dia.	Airflow @ Static Pressure	Volume	Motor Speed, rpm	Power, hp	Dia.	Ht.	Base Wd.	Housing Material		Each		Each
Open Dripproof Motor Enclosure
120/208-230V AC, Single Phase—Hardwire
16"	2,800 cfm @ 1/2 in. of H₂O 3,200 cfm @ 0 in. of H₂O	70 dBA @ 5 ft.	1,145	3/4	33 11/16"	29 1/4"	26"	Aluminum	0000000	000000000	0000000	0000000
20"	4,900 cfm @ 1/2 in. of H₂O 5,400 cfm @ 0 in. of H₂O	74 dBA @ 5 ft.	1,080	1 1/2	38 1/4"	31 3/4"	30"	Aluminum	0000000	00000000	0000000	000000
208-230/460V AC, Three Phase—Hardwire
24"	6,900 cfm @ 1/2 in. of H₂O 7,750 cfm @ 0 in. of H₂O	73 dBA @ 5 ft.	875	2	44 1/4"	39 11/16"	33"	Aluminum	0000000	00000000	0000000	000000