Durable Waterway Spa-Flo II Spa Pumps are simple to install and provide years of trouble-free use. Because of our huge buying power, you'll pay less for a complete new hot tub pump (motor & wet end) than some others charge for just a replacement motor.
- 1.5" Side Discharge
- Direct replacement for Aqua-Flo Flo-Master FMHP
Product Notes: 220 - 240V. 2-speed; easily configured for 1-speed. Waterway uses various motor manufacturers, so capacitor location may be external or internal. Order new pump unions if needed. Some brands (such as Hayward, Jacuzzi or Sta-Rite) may use non-standard fittings with different dimensions.
Speed: 2-speed: 3450 RPM high/1725 RPM low
Horsepower: 2 HP
Amperage: 8.4A high/2.6A low
Gallons Per Minute: 145 GPM (high speed)
Frame Size:48 Frame
Intake: 1.5" plumbing (2.375" O.D. pump threads)
Discharge: 1.5" plumbing (2.375" O.D. pump threads)
Discharge Type: Side
Wet End Discharge Orientation: Top (can easily be rotated)
Overall Length: 16.125"
Waterway Cross Reference: 3420820-S0Z, 3420820-0Z
AquaFlo Cross Reference: 1-00-0055, 02120-230, 02120000-1010, FMHP
Motor Cross Reference: RB805, BN51, 5KCP39TN4458X, MGT-60-5201
Warranty: 12 Month Limited Warranty
Choosing a pump based on Horsepower (HP) can be misleading. The horsepower listed in your spa manual or on old pump's label may be overinflated, inaccurate, or even left blank. Horsepower ratings are often listed as Break Horsepower (BHP), which is not the same as continuous horsepower. Selecting a pump with too much power for your spa can cause significant damage.
To avoid choosing the incorrect pump, use the Amperage rating listed on the old pump's label to find the correct replacement instead of the horsepower. The amperage rating is listed with both high/low speed for a 2 speed pump.
Determining Spa Pump Plumbing Size
Pump plumbing sizes are nominal and not actual outside diameter (O.D.) of the threaded intake or discharge. Use a tape measure and check the diameter of your old pump thread size.
- 1.5” Pump thread measures approx. 2-3/8” O.D.
- 2.0” Pump thread measures approx. 3” O.D.
- 2.5” Pump thread measures approx. 3-5/8”
Orientation of Wet End
Pump wet ends can be oriented in 90º increments to meet your installation requirements. Loosen the four through-bolts from the back of the motor and pull them back enough to disengage. Then rotate the wet end to the desired position realign and re-tighten the bolts.
Side or Center Discharge
The two spa pump form factors refer to the outflow or discharge fitting on the Wet End. Your old pump will be either Center Discharge or Side Discharge.
In most cases you need to match the existing form factor to get the components to match up. If you can use either form, select Side Discharge, which is more efficient than a Center Discharge pump of the same horsepower.
Motor Frame Size
The physical size of the pump motor is referred to as frame. Spa main pumps will have a size of either 48 frame, which are approx. 5.5" diameter, or 56 frame, which are approx. 6.5" diameter.
Since motor manufacturers do not label frame size consistently, you should determine a motor's frame size by measuring the spacing between the through-bolts on the back of the motor. Bolt spacing on a 48 frame motor will be less than 4 inches. A 56 frame motor's bolts will be spaced more than 4 inches apart.
Note: Because of their lower cost and compact size, most spa pumps in service are 48 frame. The larger 56 frame motors are a little more expensive and somewhat stronger. They tend to operate a bit cooler than 48 frame units, which can mean longer service life.
Configuring a Pump for 2 or 1 Speed Use
Our 2-speed pumps can easily be configured for 1-speed. Wire the common and high speed terminal connections, while leaving the low speed terminal blank.