⚙️ Waterway EX2 3421821-1U Spa Pump — 3.0 HP Dual Speed 230V 48-Frame | Made in USA High-Performance Jet Pump

American-engineered dual-speed power for demanding spa jet systems and XP2 replacement

📋 Product Overview

The Waterway EX2 3421821-1U is a 3.0 HP full-rated (4.0 HP SPL) dual-speed jet pump designed, engineered, and manufactured in the USA by Waterway Plastics — an industry leader in pool and spa products since 1973, based in Oxnard, California. Operating at 230V/60Hz with 12.0 Amps on high speed (3,450 RPM) and 3.5 Amps on low speed (1,725 RPM), this 48-frame side-discharge pump features 2″ center suction and 2″ side discharge with Male Buttress Thread (MBT) connections. Waterway specifically manufactured the EX2 to replace the Gecko Aqua-Flo XP2 and XP2e 48-frame pumps, sharing the same physical size for direct drop-in replacement. This pump is also used as OEM equipment in Costco AquaTerra Spas and Bullfrog Sport X hot tubs, and serves as a replacement for Caldera “Relia-Flo” pumps, Master Spas, and Emerald Spas among others. The EX2 features a high-efficiency motor with automatic thermal overload protection, Viton shaft seals designed specifically for hot tub chemical environments, and a large 6-1/2″ diameter wet end engineered for higher head pressure and improved flow performance. The wet end can be rotated every 90 degrees for versatile plumbing configurations. Two Waterway 400-5570 unions are included for 2″ PVC pipe connections. Also known as model PF-40-2N22C and Super Pro SX2. UL and CUL certified (UL File No. E128519). Backed by a 1-year manufacturer warranty.

⭐ Key Features

✅ 3.0 HP Full-Rated / 4.0 HP SPL Dual Speed — High speed at 3,450 RPM (12.0A) for powerful jet massage; low speed at 1,725 RPM (3.5A) for energy-efficient filtration and circulation

✅ Made in USA — Designed, engineered, and manufactured by Waterway Plastics in Oxnard, California using premium NSF-approved materials

✅ Direct Aqua-Flo XP2 / XP2e Replacement — Same physical size as Aqua-Flo XP2 and XP2e 48-frame pumps for direct drop-in installation

✅ OEM Equipment in Major Spa Brands — Used in Costco AquaTerra Spas, Bullfrog Sport X, Emerald Spas, and as a Caldera Relia-Flo replacement

✅ Large 6-1/2″ Diameter Wet End — Specifically designed for 48-frame motors, delivering higher head pressure and reduced noise

✅ Viton Shaft Seal — Premium seal material engineered for hot tub chemical and temperature environments

✅ Automatic Thermal Overload Protection — Built-in motor protection extends service life and prevents damage from overheating

✅ High-Efficiency Motor — Custom designed by A.O. Smith specifically for spa applications

✅ Rotatable Wet End — Discharge rotatable every 90 degrees (12, 3, 6, 9 o’clock positions) for flexible plumbing configurations

✅ Versatile Single or Dual Speed Wiring — Can be wired as a 2-speed pump or as a single-speed pump using only the high-speed connection

✅ UL and CUL Certified — Independently tested and certified for US and Canadian markets (UL File No. E128519)

✅ Unions Included — Two Waterway 400-5570 unions included, accepting 2″ PVC pipe

🔩 Technical Specifications

Specification	Value
Manufacturer	Waterway Plastics (Oxnard, CA, USA)
Product Line	EX2 Series
Part Number	3421821-1U
Also Known As	PF-40-2N22C, Super Pro SX2
Horsepower (Full-Rated)	3.0 HP
Horsepower (SPL / Uprated)	4.0 HP
Brake Horsepower (BHP)	4.0 BHP
Speed Settings	Dual Speed (2-Speed)
High Speed RPM	3,450
Low Speed RPM	1,725
Voltage	230V
Frequency	60 Hz
High Speed Amperage	12.0 Amps
Low Speed Amperage	3.5 Amps
Frame Type	48 Frame (48Y, Thru-Bolt)
Motor Diameter	5.6 inches (48 frame)
Motor Brand	A.O. Smith (per Waterway PDF; may vary — see note below)
Discharge Location	Side
Discharge Size	2″ MBT (Male Buttress Thread)
Suction Size	2″ MBT (Male Buttress Thread)
Suction Style	Center
Outside Thread Diameter	Approximately 3.0–3.1 inches
Wet End Diameter	6-1/2 inches
Seal Type	PS1100 / Viton
Wet End Position	Standard 12 o’clock; rotatable every 90° (3, 6, 9 o’clock)
Drain Plug Locations	4, 6, 9 o’clock
Overall Length	Approximately 18 inches
Height (to top of discharge)	Approximately 7-25/32 inches (7.78″)
Weight	Approximately 39 lbs
Unions	Included — 2× Waterway 400-5570 unions (accepts 2″ PVC pipe)
Cord	NOT included — use existing cord or purchase separately
Certifications	UL, CUL (UL File No. E128519)
Country of Origin	USA
Warranty	1 Year Manufacturer

⚡ Electrical Requirements

Electrical Spec	Requirement
Supply Voltage	230V
Frequency	60 Hz
Phase	Single Phase
High Speed Amps	12.0 A
Low Speed Amps	3.5 A
High Speed RPM	3,450
Low Speed RPM	1,725
Overload Protection	Automatic Thermal Overload Protection
Cord	NOT included — 4-wire 2-speed pump cord required

🔄 Compatibility Guide

Frame & Port Configuration

Specification	Detail
Frame	48 Frame (48Y, Thru-Bolt)
Motor Diameter	5.6 inches
Wet End Diameter	6-1/2 inches
Suction	2″ MBT (Center)
Discharge	2″ MBT — Side (rotatable every 90°)
Outside Thread Diameter	Approximately 3.0–3.1 inches
Union Part Number	400-5570 (accepts 2″ PVC pipe)

Designed as Direct Replacement For

Waterway specifically manufactured the EX2 to replace the following (per Waterway datasheet and SpaGuts):

Gecko Aqua-Flo XP2 / XP2e (48-Frame):

• Same physical size as Aqua-Flo XP2 and XP2e 48-frame pumps (Waterway datasheet, Electric Motor Warehouse confirmed)
• Part# 06130395-2040 (Aqua-Flo XP2 3.0 HP continuous / 4.0 BHP — SpaGuts confirmed as direct replacement)
• Part# 0613095-2040 (WaterwayParts confirmed)

OEM / Factory-Installed In

Spa Brand	Notes	Source
Costco AquaTerra Spa	Factory-installed pump	WaterwayParts confirmed
Bullfrog Sport X	Factory-installed pump	WaterwayParts confirmed
Emerald Spas	Replacement for part# 50011340 (Emerald, Great Lakes, Polynesian)	HotTubOutpost confirmed

Also Replaces

Brand	Notes	Source
Caldera Relia-Flo	Verify amp rating, voltage, and fitting match. New motor will not have the cover with heat vent connection — original cover may be used if it fits	SpaGuts confirmed
Master Spas	Part# X321000, X320420 (3HP), X320450 (2HP)	SpaGuts confirmed

Compatibility Verification Checklist

Always verify compatibility by matching these critical specifications from your existing pump:

1. Frame type — must be 48 frame (5.6″ motor diameter)
2. Voltage — must be 230V / 60Hz
3. Amperage — should be approximately 12.0A (high) / 3.5A (low)
4. Port sizes — both suction and discharge are 2″ MBT (approximately 3.0–3.1″ outside thread diameter)
5. Discharge direction — side discharge
6. Speed — dual speed (can also be wired as single speed)

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📐 Alternate Part Numbers

Primary Designations

Part Number	Notes	Source
3421821-1U	Primary Waterway EX2 Part Number	Waterway PDF confirmed
34218211U	No-hyphen format	Reed Pool Products
10-3421821-1U	HydroQuip designation	HydroQuip confirmed
PF-40-2N22C	Waterway model designation	Reed Pool Products confirmed
PF-40-2N22C 8	Extended model designation	Reed Pool Products confirmed
Super Pro SX2	Alternate product name	WaterwayParts confirmed
EX-30-2N22CE	Waterway model number (EX2 3HP line)	SpQuip confirmed

Aqua-Flo XP2 / XP2e Part Numbers This Pump Replaces

Part Number	Notes	Source
06130395-2040	Aqua-Flo XP2 3.0 HP / 4.0 BHP 48-frame 2-speed — primary replacement	SpaGuts, SpQuip, Reed Pool confirmed
0613095-2040	Aqua-Flo (alternate format)	WaterwayParts confirmed
06130395-2	Aqua-Flo XP2	Reed Pool confirmed
06630606-1	Aqua-Flo	Reed Pool confirmed
06130000	Aqua-Flo	Reed Pool, SpQuip confirmed
06130310	Aqua-Flo	SpaGuts confirmed
06130308-2	Aqua-Flo	SpaGuts confirmed
06130319-2	Aqua-Flo	SpaGuts confirmed
06115000-1040	Aqua-Flo XP2	SpQuip confirmed
06120500-2040	Aqua-Flo XP2	SpQuip confirmed
06125000-1040	Aqua-Flo XP2	SpQuip confirmed

Additional Aqua-Flo 06-Series Cross-References (SpaGuts Confirmed)

06630485-2, 06630309-2, 06630397-2, 06630450-2, 06630489-2, 06630397, 06630370-2, 06630330-2, 06630395-2, 06630176-2, 06530500-2, 06630394-2, 06630500-2, 06625485-2, 05625287-1

Aqua-Flo 07-Series Cross-References (SpaGuts Confirmed)

07830707-2, 07830306-2, 07830306-1, 07830707-2

Industry / OEM Cross-References

Part Number	Brand / Notes	Source
50011340	Emerald Spas, Great Lakes Spas, Polynesian	HotTubOutpost confirmed
X321000	Master Spas	SpaGuts confirmed
X320420	Master Spas (3HP)	SpaGuts confirmed
X320450	Master Spas (2HP)	SpaGuts confirmed
1-00-0132	Artesian / Industry code	SpaGuts confirmed
15-200-0395	Industry designation	SpaGuts confirmed
15-720-0395	Industry designation	SpaGuts confirmed
XP2553022	Aqua-Flo XP2 model	Reed Pool, SpQuip confirmed
XP2551521	Aqua-Flo XP2 model	SpQuip confirmed
XP2552522	Aqua-Flo XP2 model	SpQuip confirmed
PF-2NCF	Aqua-Flo designation	SpQuip confirmed
PF-50-2N22C4	Alternate model designation	Reed Pool confirmed
3421028-1UG285	Waterway alternate	Reed Pool confirmed
7-184834-02	Industry cross-reference	Reed Pool confirmed

Related EX2 Part Numbers (Same Pump, Different Designations)

Part Number	Notes
3421821-13	EX2 48-frame with 2″ × 2-1/2″ ports (different port configuration)
3421821-1A	Waterway Executive line (same wet end platform, different motor/product line — typically rated 4.5HP SPL)

Motor Part Numbers (For Reference — SpaGuts)

Part Number	Notes
T55CXBSR-1076	Motor only — must verify pump housing compatibility
T55MWCBB-1185	Motor only — must verify pump housing compatibility
T55MWBNN-1009	Motor only — must verify pump housing compatibility
T55CXBNN-1009	Motor only — must verify pump housing compatibility

Complete EX2 48-Frame Family (Waterway PDF Confirmed)

Single Speed:

Part Number	HP	Volts	Amps
3410610-1U	1.5 HP	115V	17.0 A
3411020-1U	2.5 HP	230V	10.0 A
3411621-1U	3.0 HP	230V	12.0 A

Dual Speed:

Part Number	HP	Volts	Amps (Hi/Lo)
3420610-1U	1.5 HP	115V	16.4 / 4.4 A
3420820-1U	2.0 HP	230V	10.5 / 2.6 A
3421021-1U	2.0 HP	230V	9.0 / 2.8 A
3421221-1U	2.0 HP	230V	8.5 / 2.8 A
3421020-1U	2.5 HP	230V	11.0 / 3.3 A
3421821-1U	3.0 HP	230V	12.0 / 3.5 A

Complete EX2 56-Frame Family (Waterway PDF Confirmed)

Single Speed:

Part Number	HP	Volts	Amps
3711621-1W	3.0 HP	230V	12.0 A

Dual Speed:

Part Number	HP	Volts	Amps (Hi/Lo)
3720821-1W	2.0 HP	230V	8.0 / 3.0 A
3721120-1W	2.5 HP	230V	11.0 / 3.3 A
3721621-1W	3.0 HP	230V	12.0 / 4.4 A
3M21621-1W	3.0 HP (Emerson)	230V	12.0 / 4.4 A

⚠️ EX2 vs Executive Note: The “-1U” suffix designates the EX2 product line. The “-1A” suffix designates the Waterway Executive product line. While they share wet end platforms, they are different product lines with different motors and may have different HP ratings. Verify the correct suffix when ordering.

💡 Need 2-1/2″ Ports? If your spa has 2″ × 2-1/2″ plumbing, the 3421821-13 variant has a 2″ suction and 2-1/2″ discharge configuration.

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🛠️ Installation Requirements

Mounting (from Waterway Installation Manual 810-0061)

Requirement	Specification
Mounting Position	Horizontal — on a level surface
Location	Below water level (flooded suction)
Surface	Level surface with adequate floor drainage
Moisture Protection	Installation area should be clear of direct water; protect pump from excessive moisture
Ventilation	Adequate clearance around motor for air cooling
Capacitor Clearance	Allow extra space for motor capacitor(s) — may be single or dual mounted externally
Shut-Off Valves	Install on both inlet and outlet for future maintenance

Plumbing (from Waterway Installation Manual)

Connection	Size
Suction	2″ MBT (Center)
Discharge	2″ MBT (Side)
Unions	Included — 2× Waterway 400-5570 (accepts 2″ PVC pipe)
Outside Thread Diameter	Approximately 3.0–3.1 inches

Installation Notes (from Waterway Installation Manual 810-0061)

⚠️ Pump must be installed below water level (flooded suction)

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

⚠️ Do NOT use pipe dope. Use only Teflon tape or other sealing compounds approved for use with plastic. Some pipe dopes not approved for plastic will cause stress cracking of plastic parts

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

⚠️ All wiring must conform to the wiring diagram on the motor nameplate or on the back of the terminal cover

⚠️ Ground motor prior to connecting electrical power — do NOT ground to a gas supply line

⚠️ GFCI protection is required by code for all hot tub and spa installations

⚠️ Pump cord is NOT included — use your existing cord or purchase separately

💡 Wet End Rotation: Loosen the four long bolts at the back of the motor, rotate the wet end to the desired position (12, 3, 6, or 9 o’clock), and retighten securely.

💡 Caldera Relia-Flo Replacement Note: The new EX2 motor will not have the cover with heat vent connection. The original motor cover with heat vent connection may be used on the new motor if it fits; otherwise retrofitting a heat vent is required.

---

🔧 Maintenance Guide

Routine Maintenance

Task	Frequency	Notes
Check for leaks	Monthly	Inspect around seal area and union connections
Inspect unions	Monthly	Hand tighten only if needed — do NOT use wrenches
Clean motor ventilation openings	Quarterly	Keep clear of debris for proper cooling
Check amperage draw	Annually	Should read within 10% of nameplate rating (12.0A high / 3.5A low)
Inspect capacitor(s)	Annually	Check for signs of swelling, leaking, or corrosion
Verify GFCI operation	Monthly	Press test button to verify GFCI interrupts power
Check shut-off valves	Quarterly	Ensure fully open during operation

Warning Signs — Replace Pump If:

• Unusual noise (grinding, screeching, or humming without rotation)
• Water leaking from the seal area
• Motor repeatedly trips the circuit breaker
• Noticeably reduced water flow or weak jets
• Motor overheating or burning smell
• Low speed no longer functions
• Capacitor failure (motor hums but won’t start)
• Amp draw exceeds 10% of nameplate rating

Troubleshooting Quick Reference (from Waterway Manual)

Symptom	Common Causes
Motor won’t start	Check voltage with voltmeter; check fuse/breaker/GFCI; check connections
Motor hums but won’t start	Seized motor, winding switch or capacitor failure
Motor is noisy	Loose mounting, bearing noise, rotor rub
Motor runs then stops	Overload, inadequate ventilation, incorrect voltage or wiring
Pump runs, no flow	Valves closed, pump above water level, air lock
Pump runs, not enough flow	Suction leak, partially closed valves, dirty impeller or filter

Seal Information

Detail	Specification
Seal Type	PS1100 / Viton
Application	Designed for hot tub chemical and temperature environments
Replacement	Replace at first sign of leakage from the seal area

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🎯 Ideal Applications

Application	Suitability	Notes
♨️ Hot tub dual-speed jet pump	✅ Yes	High-performance pump designed for larger spa installations with high jet count
♨️ Aqua-Flo XP2/XP2e replacement	✅ Yes	Specifically manufactured by Waterway as direct replacement — same physical size
♨️ Costco AquaTerra Spa	✅ Yes	Factory OEM pump (WaterwayParts confirmed)
♨️ Bullfrog Sport X	✅ Yes	Factory OEM pump (WaterwayParts confirmed)
♨️ Emerald / Great Lakes / Polynesian Spas	✅ Yes	Replaces part# 50011340 (HotTubOutpost confirmed)
♨️ Caldera Relia-Flo replacement	✅ Yes	Verify amp rating and fitting match; heat vent cover note applies
♨️ Master Spas replacement	✅ Yes	Replaces X321000, X320420 (SpaGuts confirmed)
♨️ Single-speed applications	✅ Yes	Can be wired as single-speed using only the high-speed connection
🛁 Whirlpool bath	⚠️ Check compatibility	Verify frame, port, and electrical specifications match

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❓ Frequently Asked Questions

Q: What horsepower is this pump? A: This pump is rated 3.0 HP continuous duty (full-rated) per the Waterway manufacturer datasheet. It is also listed as 4.0 HP SPL (Service Performance Level) or 4.0 BHP (Brake Horsepower) — these are different rating methods for the same pump. The continuous duty rating of 3.0 HP is the standard operational rating. High speed draws 12.0 Amps at 3,450 RPM; low speed draws 3.5 Amps at 1,725 RPM.

Q: Will this replace my Aqua-Flo XP2 or XP2e pump? A: Yes. Waterway specifically designed the EX2 to replace the Aqua-Flo XP2 and XP2e 48-frame pumps. The EX2 is the same physical size for direct drop-in installation. Verify your existing pump’s amperage, voltage, frame size (48-frame), and port sizes (2″) before ordering.

Q: What is the difference between the -1U and -1A suffix? A: The “-1U” suffix designates the EX2 product line. The “-1A” suffix designates the Waterway Executive product line. While they share wet end platforms, they are different product lines with different motors and may have different HP ratings (the -1A Executive is typically rated higher at 4.5HP SPL). Verify the correct suffix when ordering.

Q: Is this pump made in the USA? A: Yes. Waterway Plastics designs, engineers, and manufactures this pump in Oxnard, California, USA using premium NSF-approved materials.

Q: What size are the ports? A: Both suction (center) and discharge (side) are 2″ MBT (Male Buttress Thread). The outside thread diameter measures approximately 3.0–3.1 inches. Two Waterway 400-5570 unions that accept 2″ PVC pipe are included.

Q: What voltage does this pump require? A: 230V / 60Hz single phase. All electrical installation must be performed by a licensed electrician.

Q: Does this pump include unions and a cord? A: Two Waterway 400-5570 unions are included (accepting 2″ PVC pipe). A pump cord is NOT included — you will need to use your existing cord or purchase a new 4-wire dual-speed pump cord separately.

Q: Can I rotate the wet end? A: Yes. The discharge can be rotated every 90 degrees (12, 3, 6, or 9 o’clock positions) by loosening the four long bolts at the back of the motor.

Q: Will this fit my Costco AquaTerra spa? A: Yes. The 3421821-1U is used as OEM equipment in Costco AquaTerra Spas (confirmed by WaterwayParts.com).

Q: Will this fit my Bullfrog Sport X? A: Yes. This pump is used in Bullfrog Sport X hot tubs (confirmed by WaterwayParts.com).

Q: Can I use this to replace my Caldera Relia-Flo pump? A: Yes, the EX2 is a replacement option for Caldera Relia-Flo pumps. Verify motor amp rating, voltage, and fitting match. Note that the new EX2 motor will not have the cover with heat vent connection — the original cover may be used on the new motor if it fits, otherwise retrofitting a heat vent is required.

Q: What warranty is included? A: 1-year manufacturer warranty from Waterway Plastics. Contact Parts4Tubs for full warranty terms.

Q: How do I know if my pump needs replacing? A: Signs include unusual noise (grinding, screeching), water leaking from the seal area, reduced water flow, the motor tripping the circuit breaker, low speed failure, or the motor humming but not starting (capacitor failure).

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 installations.

Q: Should I hand tighten or wrench-tighten the unions? A: Per Waterway’s installation manual: HAND TIGHTEN UNIONS ONLY. Do NOT use a wrench or any adhesives or solvents. Do NOT use pipe dope — use only Teflon tape or sealing compounds approved for use with plastic.

📥 Downloads & Resources

📄 Waterway EX2 Datasheet / Specifications PDF — Complete EX2 specifications, part number matrix, and performance chart (Waterway Plastics official)

📄 Waterway 48/56 Frame Executive, EX2, & Viper Pump Installation Manual (810-0061) — Installation instructions, wiring guide, troubleshooting chart, and exploded parts diagram (Waterway Plastics official)

🏆 Why Choose the Waterway EX2 3421821-1U

✅ Made in USA — Designed, engineered, and manufactured by Waterway Plastics in California since 1973

✅ Direct Aqua-Flo XP2/XP2e Drop-In Replacement — Same physical size eliminates guesswork and plumbing modifications

✅ Dual-Speed Energy Savings — Low speed at just 3.5 Amps provides 24/7 filtration and circulation, dramatically reducing operating costs

✅ OEM-Quality for Major Spa Brands — Used as factory equipment in Costco AquaTerra, Bullfrog Sport X, and more

✅ Premium Viton Seals — Engineered specifically for harsh hot tub chemical environments

✅ Large 6-1/2″ Wet End — Higher head pressure and improved flow performance compared to standard wet ends

✅ UL and CUL Certified — Independently tested and certified (UL File No. E128519)

✅ 1-Year Manufacturer Warranty — Full warranty support from Waterway Plastics

🤝 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

✅ Full warranty support

✅ Hassle-free returns

✅ Replacement seals, wet ends, impellers, unions, and motor parts available

✅ Dedicated customer service team

💫 Summary

The Waterway EX2 3421821-1U is a 3.0 HP full-rated (4.0 HP SPL) dual-speed, 230V/60Hz jet pump drawing 12.0/3.5 Amps at 3,450/1,725 RPM. Made in the USA by Waterway Plastics, this 48-frame pump features 2″ MBT center suction and 2″ MBT side discharge, and was specifically manufactured as a direct drop-in replacement for Gecko Aqua-Flo XP2 and XP2e 48-frame pumps — sharing the same physical size. Also used as OEM equipment in Costco AquaTerra Spas and Bullfrog Sport X. Features high-efficiency A.O. Smith motor with automatic thermal overload protection, large 6-1/2″ diameter wet end, Viton shaft seals, and rotatable discharge. UL and CUL certified (UL File No. E128519). Unions included. Backed by a 1-year manufacturer warranty from Waterway Plastics. Available now at Parts4Tubs.

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	Magic Plastics Union 0602-15 (1.5″ Pump Union) | 1-1/2″S x 1-1/2″FBT Union, Pump, Magic, 1-1/2"S x 1-1/2"FBT (Industry Standard) w/ O-Ring	$6.36 Max: 575 Min: 1 Step: 1 Add to cart
	Magic Plastics Union 0602-20 (2″ Pump Union) | 2″S x 2″FBT w/ O-Ring Union, Pump, Magic, 2"S x 2"FBT (Industry Standard) w/ O-Ring	$8.00 Max: 491 Min: 1 Step: 1 Add to cart
	Waterway Union 400-6010 | 2-1/2″ Union Nut with 2-1/2″ Slip tailpiece and o-ring (2.5″ union) Union, Pump, Waterway, 2-1/2"FBT x 2-1/2"S	$14.77 Max: 145 Min: 1 Step: 1 Add to cart
	1 Speed Pump / Blower / AMP Cord | 21086 Amp Plug, Pump, 1-Speed, 14/3, 4-Pin, 5' Cord, White	$24.71 Max: 426 Min: 1 Step: 1 Add to cart
	Balboa Amp Plug 21087 (For 2 Speed Pumps) Amp Plug, Pump 1 (2-Speed) 14/4, 72" Long, White	$31.72 Max: 172 Min: 1 Step: 1 Add to cart

Hot Tub Pump Collar & Union Size Chart

Imperial & Metric Specifications

Union Size	Collar Size	Thread OD	Union OD	O-Ring Size
1.5" Female Buttress Thread (FBT)	2.5" / 64mm (Tip to Tip) Measurement	2-1/2" 64mm	2-13/16" 71mm	2-5/16" OD 59mm
2" Female Buttress Thread (FBT)	3.1" / 78mm (Tip to Tip) Measurement	3-1/16" 78mm	3-3/8" 81mm	2-15/16" OD 75mm
2.5" Female Buttress Thread (FBT)	3.6" / 91mm (Tip to Tip) Measurement	3-5/8" 91mm	4-1/4" 108mm	3-7/16" OD 87mm

Important Notes

The union "size" (1.5", 2", 2.5") is nominal and doesn't correspond to any actual measurement.

Collar size is measured from thread tip to thread tip on the pump outlet.

Most hot tub pumps use Female Buttress Thread (FBT) - 98% of applications.

O-ring gaskets may vary between manufacturers - measure your existing gasket for accuracy.

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
• Pipe wrench
• Adjustable wrench
• Screwdriver
• Pipe sealant (thread tape or plumber's putty)
• PVC primer and cement (if you have PVC plumbing)
• Teflon tape (for threaded connections)

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. Use a pipe wrench or adjustable wrench to loosen and remove the fittings. 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. Ensure that you use the appropriate sealant or Teflon tape on threaded connections to prevent leaks.

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, ensuring that all connections are tight and secure. If your hot tub uses PVC plumbing, use PVC primer and cement to bond the connections properly.

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.