BLOWER SIZING

	HORSEPOWER
To Get This	Divide This	By This
Horsepower	Kwatts	0.746
Horsepower	Watts	746
Horsepower	Torque (ft. lbs.) X RPM	33000
Horsepower	Torque (ft. lbs.) X RPS	550
Horsepower required to pump water at a given rate to a given Height,assuming 100% eff. AKA Water	GPM x TDH (ft.)	3960
Horsepower	GPH X TDH (psi)	103000
Brake HP	Water HP	Pump eff.

BLOWER MOTOR SIZE	VOLTS	AMPS	MAXIMUM INCHES OF WATER DEPTH	JETS ONLY RECOMMENDED NUMBER OF JETS
1 HP	120V	6.6	35 in.	5 to 10
1-1/2 HP	120V	7.4	45 in.	9 to 15
2 HP	120V	9.3	55 in.	12 to 17
1 HP	240V	3.9	30 in.	4 to 9
1-1/2 HP	240V	4.3	40 in.	8 to 13
2 HP	240V	5	50 in.	12 to 17

Measure total depth of water in spa (not total spa depth)

Add - 1 in. water for each 10 ft. of 2 in. air pipe Add 1/2 in. water for each 90 deg. 2 in. elbow

Compare your total with maximum inches of water column and select that size or the next size higher blower than your total, in your selected voltage.

The number of holes in the air channel (both floor and seat) should be approximately 1.6 sq. in. total plus or minus .5

1/8 in. hole = .0123 sq. in. 3/16 in. hole = .0276 sq. in.

5/32 in. hole = .0192 sq. in. 1/4 in. hole = .0491 sq. in.