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Waterway
Waterway EX2 Spa Pump 4.0 HP 230 Volts 2 Speed 56FR (3721621-1W)
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Spa pump 3721621-1W is a Waterway EX-2 that is 4.0 Horsepower 230 volt 2 speed 56 frame pump. EX2 pumps have a 2" intake and side discharge (measures 3" across) The 3721621-1W is a 56 frame, you will want to check your current pumps motor label or measure your pump. Putting in a different frame size spa pump typically is not a problem as most spas have some flex in the plumbing but be warned it may not line up perfectly if you choose to change frame sizes.
If you have questions reading the information from your pump motor please see our motor label page, or watch our quick video. As always we are here to help if you have a question email or call us.
This Waterway EX-2 Pump Specs:
- 4.0 Horsepower
- 56 Frame
- 230 Volts
- 2 Speed
- 12 Amps.
- 2" Side Discharge
- 2" Intake
Waterway EX-2 Features
- Made in USA from highest quality materials with UL and CUL certifications
- Equipped with the highest quality Viton Seals. Means this pump can hand salt systems.
- Equipped with high efficiency electrical motors, custom designed for Spa applications
EX-2 Pump Wiring Instructions Here
Technical and Installation:
- Pump is manufactured in the wet-end orientation shown, but you can simply rotate you wet end to match your spa plumbing, if needed.
- Pump is manufactured without a pump amp cord. You will need to use your existing pump amp cord or purchase a new one.
- Please see How to Wire a Spa Pump to wire the pump amp cord.
Manufacturer: Waterway
Manufacturer Number: 3721621-1W
Manufacturer Warranty: 1 year part
Remember we have hands on service experience with every product we sell, so we are available with tech support, problem diagnoses, installation help, and should it be needed warranty issues.
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Frequently Asked Questions
A spa air blower forces air into the spa's air plumbing system to create bubbles through the air jets. This produces the bubbling massage effect many hot tubs are known for and enhances the overall hydrotherapy experience.
No. Some spas use only water jets that mix air through a venturi system. Spas that include a dedicated air blower produce stronger bubbles and a more intense massage effect.
Common signs of a failing spa air blower include: No bubbles coming from the air jets, Loud humming or grinding noises, The blower not turning on, Weak or inconsistent airflow. If your spa previously had strong bubbles and they suddenly stopped, the air blower may need to be replaced.
Spa air blowers are commonly available in 1.0 HP, 1.5 HP, and 2.0 HP models. The correct size depends on the number of air jets and the plumbing length in your spa. Matching the horsepower of your existing blower is usually the best option.
Yes. If water flows backward into the blower it can damage the motor. This is why most spa systems include a check valve in the air line to prevent water from reaching the blower.
A loud blower can be caused by: Worn motor bearings, Debris inside the blower housing, Airflow restrictions in the plumbing, A failing blower motor. If the noise continues to get worse, replacement may be necessary.
Many spa owners can replace an air blower if they are comfortable with basic electrical connections. However, if you are unsure about wiring or spa electrical components, professional installation is recommended.
No. An air blower simply pushes air into the spa plumbing. Some models have heated air features that warm the air slightly for comfort, but they do not heat the spa water.