🔧 Waterway Hi-Flo II 1.5 HP Spa Pump – Dual-Speed 115V 48-Frame Side Discharge Jet Pump (3420610-10)

Powerful dual-speed jet performance with high-efficiency side discharge design

📋 Product Overview

The Waterway Hi-Flo II (model 3420610-10) is a 1.5 HP, dual-speed, side discharge spa jet pump built for hot tub and spa applications requiring both strong jet power and energy-efficient filtration circulation. Designed, engineered, and manufactured in the USA at Waterway Plastics’ facility in Oxnard, California, this 48-frame pump delivers high-volume water flow through its oversized 6-1/2 inch diameter wet end, producing up to 60% greater efficiency compared to traditional center discharge pump designs.

The dual-speed motor allows owners to run at high speed for powerful hydrotherapy jet action and switch to low speed for quiet, energy-saving filtration cycles. The rotatable wet end simplifies installation by allowing the discharge port to be positioned to match existing plumbing without reworking pipe runs. Operating on 115V/60Hz power, this pump is a direct OEM replacement for a wide range of Waterway Hi-Flo and Hi-Flo II models, making it an ideal choice for both new installations and pump replacements in residential hot tubs and spas.

⭐ Key Features

✅ Dual-Speed Motor – High speed for jet-powered hydrotherapy, low speed for quiet and efficient filtration cycles

✅ High-Volume Side Discharge – Delivers up to 60% greater efficiency than center discharge pump designs for faster filtration

✅ 48-Frame Thru-Bolt Motor – Industry-standard 48Y frame size for broad compatibility with existing spa equipment bases

✅ 1.5 HP Motor Rating – Provides strong water flow suitable for multi-jet hot tub and spa systems

✅ 115V / 60Hz Operation – Standard North American residential voltage for straightforward electrical connections

✅ Rotatable Wet End – Discharge port can be repositioned to align with existing plumbing, reducing installation time

✅ Large 6-1/2 Inch Wet End – Oversized volute generates higher head pressure for improved jet performance

✅ Viton Shaft Seal – Silicone carbide seal faces with Viton bellows and 316 stainless steel casing for chemical resistance and longevity

✅ 2 Inch Plumbing Connections – Both suction and discharge ports use 2 inch Male Buttress Thread (MBT) for standard spa plumbing

✅ California Title 20 Compliant – Meets energy efficiency requirements for the California market

✅ Made in the USA – Designed, engineered, and manufactured by Waterway Plastics in Oxnard, California

✅ 1-Year Manufacturer Warranty – Backed by Waterway’s standard manufacturer warranty

🔩 Technical specifications

⚡ Electrical Requirements

Amperage Note

⚠️ Important: Waterway reserves the right to change motors paired with the Hi-Flo II wet end. Amperage ratings may vary depending on the specific motor shipped with the pump. Two amp rating ranges have been documented across sources for this model:

Rating	High Speed Amps	Low Speed Amps
Amps	13.3 A	4.1 A

The motor nameplate on your specific pump will display the exact amperage rating. Always size circuit breakers, wiring, and GFCI protection based on the amperage listed on the actual motor nameplate rather than catalog specifications.

⚠️ IMPORTANT ELECTRICAL SAFETY REQUIREMENTS:

• All electrical work must be performed by a licensed electrician in accordance with the National Electrical Code (NEC) and local building codes
• Hot tubs require GFCI (Ground Fault Circuit Interrupter) protection
• A dedicated circuit is required — do not share with other appliances
• Wire all connections per the wiring diagram on the motor nameplate or terminal cover
• Ensure proper grounding and bonding per NEC requirements
• Improper grounding can cause serious injury and damage to the motor, voiding the warranty

🔄 Compatibility Guide

Frame and Mounting Specifications

This pump uses a 48-Frame Thru-Bolt motor, which is the most common frame size for residential hot tub and spa jet pumps. The 48-frame designation refers to the motor’s bolt pattern and physical dimensions.

This Pump’s Configuration

• 📍 Frame: 48-Frame Thru-Bolt
• 📍 Wet End: 6-1/2 inch diameter side discharge
• 📍 Suction: 2 inch MBT, Center
• 📍 Discharge: 2 inch FPT/MBT, Side
• 📍 Thread OD: Approximately 3-1/16 inches (3.1 inches) on both ports

Plumbing Connection Notes

The 2 inch plumbing designation is nominal and does not refer to the outside diameter of the threaded connections. The actual outside diameter of the pump union threads measures approximately 3-1/16 inches (3.1 inches). When matching this pump to existing plumbing, measure the outside diameter of the threaded connections on your current pump for accurate comparison. Use Waterway tailpiece assemblies or compatible 2 inch pump unions for connections.

Cross-Reference and Alternate Part Numbers

The Waterway Hi-Flo II 3420610-10 is listed under the following alternate part numbers across various distributors and systems:

Alternate Part Number	Notes
3420610-10	Primary Waterway OEM Part Number
3420613	Previous/alternate Waterway part number
3J20610	Alternate distributor code
5032-150	Alternate reference
625230	Alternate distributor number
R55CXFCM-0305	OEM cross-reference
WW342061010	Alternate format (no dashes)
WWP-10-141	Alternate distributor code
SD-15-2N11CD	Waterway legacy part number
SD-15-2N11C	Waterway legacy part number
SD-15-2N11F	Waterway legacy part number
SD-25-2N11CD	Waterway legacy part number (3.1 inch OD threads)
P215HF2012	Alternate cross-reference
342061010	Compact format (no dashes)
1-00-0084	Alternate reference
10-0204-3M	Alternate distributor code
300-5010SD / 3005010SD	Alternate Waterway part number
WW3005010SD	Alternate format
34-270-3624	—

🔧 Parts and fittings for this

Commonly replaced parts

Parts commonly replaced on this item that we stock.

Replaces These Waterway Hi-Flo / Hi-Flo II Models

The 3420610-10 serves as a direct replacement for the following Waterway pump models:

• 3420610-2041
• 3420610-0045
• 3420610-0087
• 342061A-10
• 3420610-H10 (horizontal mount version — add “-H” suffix)
• 3410612-10 (1-speed version — note: this is a single-speed pump; the 3420610-10 is dual-speed)
• 3410612-H10 (1-speed horizontal version)

⚠️ Before Ordering: Always verify your existing pump’s frame size (48 vs. 56), voltage (115V vs. 230V), speed configuration (1-speed vs. 2-speed), and plumbing connection sizes (2 inch vs. 2-1/2 inch) before purchasing a replacement. The 230V version of this pump is model 3420620-10 — do not interchange 115V and 230V models.

🛠️ Installation Requirements

Mounting and Location

Requirement	Specification
Mounting Position	Below water level (flooded suction required)
Base Surface	Solid, level surface
Drainage	Installation area should have adequate floor drainage
Moisture Protection	Pump should be protected from excessive moisture
Access Clearance	Allow adequate access area for future maintenance
Shut-Off Valves	Install on both inlet and outlet for future service

Plumbing Connections

Connection	Size	Thread Type
Suction (Inlet)	2 inch	Male Buttress Thread (MBT)
Discharge (Outlet)	2 inch	FPT / Male Buttress Thread (MBT)
Union Type	Waterway tailpiece assemblies recommended

Plumbing Installation Notes

⚠️ HAND TIGHTEN UNIONS ONLY! Do NOT use a wrench or any adhesives or solvents on pump unions

⚠️ Do NOT use pipe sealant (pipe dope) on plastic threads. Use only Teflon tape or other sealing compounds approved for use with plastic. Some pipe sealants cause stress cracking of plastic parts

⚠️ The wet end can be rotated to align the discharge port with existing plumbing — this feature eliminates the need for additional plumbing fittings in most installations

⚠️ Pump must be installed below water level to ensure flooded suction. If the pump must be installed near or above the waterline (common with in-ground spas), a pump pot is required to prevent water from draining back when the motor is off

⚠️ Pressure testing for new installations should not exceed 40 PSI. Ensure all air is removed from the system during pressure testing

Cord and Electrical Connection

⚠️ This pump does NOT include a power cord or unions. The pump cord is sold separately:

• For AMP plug connection: Use cord model 30-1001C (14/4 gauge, 2-speed)
• For mini JJ adapter: Use adapter cord 30-1220-L6 to convert AMP to mini JJ connection

The cord and plug provided with the pump (sold separately) is intended to be used with a mating spa pack connector. All wiring must conform to the wiring diagram on the motor nameplate or on the back of the terminal cover.

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🔧 Maintenance Guide

Routine Maintenance

Task	Frequency	Notes
Check for leaks	Monthly	Inspect around shaft seal and union connections
Inspect union connections	Monthly	Hand tighten if needed — do not use tools
Clean strainer/filter basket	As needed	Remove debris to maintain proper flow
Check motor amperage	Annually	Should match rating on motor nameplate
Inspect motor ventilation	Quarterly	Keep air vents clear of debris and obstructions
Check mounting bolts	Quarterly	Tighten if loose due to vibration
Inspect drain plugs	Quarterly	Ensure they are secure at 3, 6, and 9 o’clock positions

Warning Signs — Replace Pump If:

• Unusual noise such as grinding, screeching, or humming without rotation
• Water leaking from the shaft seal area
• Motor repeatedly trips the circuit breaker
• Noticeably reduced water flow through jets
• Motor overheating or unusually hot to the touch
• Visible corrosion or damage to the wet end housing

Shaft Seal Replacement

• 📍 Seal Type: PS-1000
• 📍 Waterway Part Number: 319-3100B
• 📍 Seal Material: Silicone carbide faces, Viton bellows, 316 stainless steel casing
• 📍 Shaft Diameter: 5/8 inch

⚠️ Replace the shaft seal at the first sign of water leakage from the seal area. When replacing the seal, inspect the impeller for damage — water leaking past the seal often reaches the motor shaft and can cause the impeller to swell or corrode. Apply water-based assembly lubricant (P-80 Sealube or similar) during seal installation. Do NOT use PTFE, silicone, or petroleum-based lubricants.

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🎯 Ideal Applications

Application	Suitability	Notes
♨️ Hot tub jet pump	Yes	Primary application — provides both high-speed jet power and low-speed filtration
♨️ Spa circulation and filtration	Yes	Low speed delivers quiet, energy-efficient filtration cycles
♨️ Above-ground spa/pool pump	Yes	Suitable for above-ground applications with flooded suction
🛁 Whirlpool bath	See note	Verify frame size and plumbing compatibility before use in bath applications

❓ Frequently Asked Questions

Q: What horsepower is this pump? A: This pump is rated at 1.5 HP (SPL rating). It operates on 115V at 60Hz with a dual-speed motor.

Q: Will this fit my hot tub? A: This pump uses a 48-frame thru-bolt motor with a 6-1/2 inch diameter side discharge wet end and 2 inch plumbing connections on both suction (center) and discharge (side). Check your existing pump’s frame type (48 vs. 56), wet end size, plumbing connection sizes, and port thread outside diameter (should be approximately 3-1/16 inches or 3.1 inches) to confirm compatibility.

Q: What voltage does this pump require? A: 115V / 60Hz single phase. All electrical installation must be performed by a licensed electrician with GFCI protection. If your existing pump runs on 230V, you need model 3420620-10 instead.

Q: Does this pump run on 115V or 230V? A: This specific model (3420610-10) is 115V only. Using 230V power will damage the motor. The 230V equivalent is model 3420620-10. Always check the voltage on your existing pump before ordering.

Q: Is this a single-speed or dual-speed pump? A: This is a dual-speed pump. High speed delivers full jet power for hydrotherapy, while low speed provides quiet, energy-efficient filtration. The single-speed version is model 3410612-10.

Q: What size are the ports? A: Both suction and discharge ports are 2 inch nominal size. The actual outside diameter of the union threads measures approximately 3-1/16 inches (3.1 inches). Suction is center-mounted; discharge is side-mounted.

Q: Does the pump come with a cord? A: No. The pump cord is sold separately. For AMP plug connection, use cord model 30-1001C. For mini JJ connection, use the AMP cord with adapter cord 30-1220-L6.

Q: Does the pump come with unions? A: No. Pump unions with o-rings are sold separately. Use Waterway-compatible 2 inch pump unions.

Q: What warranty is included? A: The Waterway Hi-Flo II 3420610-10 carries a 1-year manufacturer warranty. Contact Parts4Tubs for full warranty terms and support.

Q: How do I know if my pump needs replacing? A: Common signs include unusual noise (grinding or screeching), water leaking from the shaft seal, reduced jet pressure, the motor tripping the circuit breaker repeatedly, or the motor running excessively hot.

Q: Do I need a GFCI breaker? A: Yes. GFCI (Ground Fault Circuit Interrupter) protection is required by the National Electrical Code (NEC) for all hot tub and spa electrical installations.

Q: Can I rotate the wet end to match my plumbing? A: Yes. The Hi-Flo II wet end is designed to be rotatable, allowing the side discharge port to be positioned to align with your existing plumbing layout.

Q: What is the difference between this pump and the Waterway Executive? A: Both the Hi-Flo II and the Executive use 48-frame motors with 2 inch plumbing connections, but they have different wet end designs. The Hi-Flo II uses a high-volume side discharge wet end, while the Executive series has its own wet end configuration. The seal (PS-1000 / 319-3100B) is the same across both models. Check your existing pump’s specific model number to ensure proper replacement.

Q: Why do different retailers list different amperages? A: Waterway reserves the right to change the motor paired with the Hi-Flo II wet end. Amperage ratings may vary depending on which motor is supplied. The manufacturer website lists 16.4A/4.4A (high/low), while some retailers list 13.3A/4.1A. Always reference the amperage on your specific pump’s motor nameplate for accurate electrical sizing.

🏆 Why Choose the Waterway Hi-Flo II 3420610-10

✅ Proven Performance – 60% more efficient than center discharge designs, delivering higher water volume for faster filtration and stronger jet action

✅ American Quality – Designed, engineered, and manufactured in the USA by Waterway Plastics, a trusted name in pool and spa equipment since 1973

✅ Chemical-Resistant Seals – Viton shaft seal with silicone carbide faces and 316 stainless steel casing stands up to spa chemicals and extends pump life

✅ Flexible Installation – Rotatable wet end eliminates the need to modify plumbing during pump replacement, saving time and labor costs

✅ Energy-Smart Dual-Speed – Low-speed operation reduces energy consumption during filtration cycles while maintaining clean, clear water

✅ Wide Compatibility – Replaces numerous Hi-Flo and Hi-Flo II models with extensive cross-reference part numbers for confident ordering

✅ 1-Year Warranty – Backed by Waterway’s manufacturer warranty with support available through Parts4Tubs

🤝 Why Buy from Parts4Tubs

✅ US-based support for American customers

✅ Fast shipping across the United States

✅ Expert advice from spa and hot tub specialists

✅ Competitive pricing in USD

✅ Full warranty support

✅ Hassle-free returns

✅ Replacement seals, cords, unions, and parts available

✅ Dedicated customer service team

✨ Summary

The Waterway Hi-Flo II 3420610-10 is a 1.5 HP, dual-speed, 115V/60Hz spa jet pump featuring a high-efficiency side discharge design in a standard 48-frame configuration. With 2 inch MBT plumbing connections, a rotatable wet end, Viton shaft seal, and California Title 20 compliance, this American-made pump delivers reliable jet power and energy-efficient filtration for residential hot tubs and spas. Order with confidence from Parts4Tubs — your US-based spa parts specialist.

Unions and pump cords: pick the union size that matches your pump's ports (see the size chart below), and a 4-wire cord for a 2-speed pump.

How do I Replace a Hot Tub Pump?

Here's a general step-by-step guide on how to replace a hot tub pump. Keep in mind that the specific steps may vary depending on your hot tub's make and model, so it's essential to consult your hot tub's manual for model-specific instructions. If you're not comfortable with this procedure, it's a good idea to seek professional assistance.

Materials You'll Need:

• Replacement pump
• Screwdriver
• New union O-rings
• A strap wrench, only if a union nut is stuck
• PVC primer and cement, only if you are gluing in new tailpieces

Procedure:

1. Turn Off the Power: Before you begin, ensure the hot tub's power supply is turned off at the circuit breaker or disconnect switch. Safety should always be a priority when working with electrical components.

2. Drain the Hot Tub: If your hot tub is not already empty, you'll need to drain it. Follow your hot tub's manual or manufacturer's instructions for proper draining. (You might not need to do this if you can lock the pump off with the gate valves)

3. Locate the Pump: Identify the location of the existing pump in your hot tub. It's usually located near the equipment area or in a designated pump compartment.

4. Disconnect the Electrical Wiring: Carefully disconnect the electrical wiring from the old pump. This typically involves removing the electrical conduit cover, unscrewing wire nuts, and disconnecting the wires from the terminals. Be sure to note the wire connections or take a picture for reference when connecting the new pump.

5. Disconnect the Plumbing: Depending on your hot tub's plumbing setup, you'll need to disconnect the plumbing connections to the pump. Unscrew the union nuts by hand. If one is stuck, use a strap wrench rather than a pipe wrench, which can crack the nut. Be prepared for some water spillage when disconnecting the plumbing.

6. Remove the Old Pump: Once the electrical and plumbing connections are detached, carefully remove the old pump from its mounting position. Some pumps may be secured with mounting brackets or bolts.

7. Prepare the New Pump: If the new pump is not pre-assembled, you may need to attach fittings, unions, or adapters to match your hot tub's plumbing. Pump unions use buttress threads that seal on an O-ring, so fit new O-rings and hand-tighten the nuts. Do not use thread tape, pipe dope or sealant on them.

8. Mount the New Pump: Position the new pump in the same location as the old one and secure it in place using the mounting brackets or bolts.

9. Reconnect Plumbing: Reconnect the plumbing to the new pump, hand-tightening the union nuts. If you are gluing in new PVC tailpieces, use PVC primer and cement on those joints.

10. Reconnect Electrical Wiring: Reconnect the electrical wiring to the new pump, following the notes or pictures you took earlier. Make sure all wires are properly connected and secure.

11. Turn On the Power: Restore power to the hot tub by switching on the circuit breaker or reconnecting the disconnect switch.

12. Test the Pump: Turn on the hot tub's pump to ensure that it's working correctly. Check for any signs of leaks or irregularities in the plumbing connections.

13. Refill the Hot Tub: Once you've confirmed that the new pump is functioning properly, refill the hot tub with water.

14. Check for Leaks: Inspect the plumbing connections for any leaks. If you find any, turn off the pump, drain the tub again, and reseal the connections as needed.

15. Monitor: Keep an eye on the pump and plumbing for the next few days to ensure everything is functioning correctly and that there are no further issues.

Remember that this is a general guideline, and the specific steps may vary based on your hot tub's design. If you're unsure or uncomfortable with any aspect of this process, please do get in touch, happy to help.

How do I know what size hot tub pump I have?

Determining the size of your hot tub pump is an important step when it comes to maintenance or replacement. To find out the size of your hot tub pump, follow these steps:

1. Check the Manual: The easiest way to determine the size of your hot tub pump is to consult the owner's manual or user documentation that came with your hot tub. The manual typically contains detailed information about the specifications and components of your hot tub, including the pump.

2. Look at the Pump Housing: If you don't have access to the manual or it doesn't provide the information you need, inspect the pump itself. Most hot tub pumps have a label or plate on the pump housing that displays essential details, including the pump's model number, manufacturer, and specifications. You can then send that to me or Google it.

3. Measure the Pump: If the label is missing or damaged, you can measure the pump's dimensions. Measure the diameter of the pump's wet end (the part where the water flows) and the length of the wet end. These measurements can help identify the size and capacity of the pump.

4. Consult the Manufacturer: If you can't find the information on the pump or in the manual, contact the hot tub manufacturer or a reputable dealer. Provide them with your hot tub's model and serial number, and they should be able to identify the correct pump size for your specific hot tub.

5. Online Research: You can also search online using the pump's model number or hot tub's make and model. Many manufacturers provide detailed information about their products on their websites, and you may find specifications for your pump model.

Once you have determined the size and specifications of your hot tub pump, you can proceed with maintenance, repairs, or replacement if necessary. Keep in mind that replacing a hot tub pump with the same size and capacity as the original is crucial to ensure proper water circulation and filtration in your hot tub. If you're unsure about any aspect of this process, get in touch, always happy to help.