📥 Downloads & Resources

📄 Pentair HydroBoost Installation and User’s Guide (PDF) – Complete installation instructions, wiring diagrams, performance curves, troubleshooting, and maintenance

⚡ Pentair HydroBoost 360526 Booster Pump – 0.8 THP Energy Star Certified

Energy-efficient, whisper-quiet booster pump with TEFC motor for pressure-side pool cleaners

♨️ Product Overview

The Pentair HydroBoost (360526) is a premium 0.8 THP single-speed booster pump designed to deliver high-pressure water flow for pressure-side automatic pool cleaners. Engineered by Pentair — one of the most trusted names in pool and spa equipment — this next-generation booster pump combines energy efficiency, reliability, and whisper-quiet operation in a compact package that is approximately one-third smaller than traditional booster pumps.

Featuring a Totally Enclosed Fan-Cooled (TEFC) motor that protects internal components from moisture and debris, the HydroBoost delivers 50 PSI at 13.2 GPM through its innovative 5-stage hydraulic design. The pump operates on dual voltage (115V/230V) with a convenient voltage selection switch, uses larger 1″ NPT connections for improved flow efficiency, and is factory preset for 230V operation. EPA Energy Star certified for reduced energy consumption — saving up to 25% on energy costs compared to conventional booster pumps — the HydroBoost is UL and cUL listed for safe use in the United States and Canada. Backed by Pentair’s proven quality, this pump directly replaces the Pentair LA-MS05 and is compatible with all leading pressure-side pool cleaners.

✨ Key Features

✅ 0.8 THP Motor with TEFC Enclosure – Totally Enclosed Fan-Cooled motor keeps internal components dry, reducing the chance of motor burnout and extending service life

✅ EPA Energy Star Certified – Saves up to 25% on energy costs compared to conventional booster pumps with a Weighted Energy Factor (WEF) of 0.62

✅ 5-Stage Hydraulic Design – Delivers 50 PSI at 13.2 GPM for powerful, consistent pressure-side cleaner performance

✅ Dual Voltage (115V/230V) – Factory preset for 230V with a built-in voltage selection switch for easy conversion to 115V

✅ 1″ NPT Connections – Larger port size supports better flow and improved energy efficiency over standard 3/4″ booster pumps

✅ Whisper-Quiet Operation – Maximum noise level of 75 dB(A) for reduced disruption during pool cleaning cycles

✅ Compact Footprint – Approximately 1/3 smaller than traditional booster pumps for easy installation in tight equipment areas

✅ Hose and Adapters Included – Ships with flexible hose kit and all necessary adapters for quick installation or retrofit

✅ Corrosion-Proof Construction – Durable materials designed to withstand pool chemistry and outdoor conditions

✅ UL / cUL Listed – Evaluated to UL 1081 and CSA C22.2 for safe residential pool use in the US and Canada

✅ IP44 Protection Rating – Motor housing protected against splashing water and solid objects

🔩 Technical Specifications

Specification	Value
Manufacturer	Pentair
Model	HydroBoost
MPN	360526
Pump Type	Booster Pump
Application	Pressure-Side Pool Cleaners
Motor Power	0.8 THP (Total Horsepower)
Weighted Energy Factor (WEF)	0.62
Speed	Single Speed
RPM	3,450
Voltage	115V / 230V (Dual Voltage)
Frequency	60 Hz
Phase	Single
Motor Type	Two-Pole
Amperage (115V)	9.0 A
Amperage (230V)	4.5 A
Factory Preset Voltage	230V (field-switchable to 115V)
Pressure at 13.2 GPM	50 PSI
Hydraulic Design	5-Stage
Motor Enclosure	TEFC (Totally Enclosed Fan-Cooled)
Motor Frame	IEC 71
Insulation Class	F
Protection Rating	IP44
Inlet Port	1″ NPT (Female Pipe Thread)
Outlet Port	1″ NPT (Female Pipe Thread)
Suction Style	Top
Discharge Style	Top
Maximum Noise Level	75 dB(A)
Maximum Ambient Temperature	122°F (50°C)
Maximum Water Temperature	104°F (40°C)
Maximum Salt Content	0.4%
pH Range	4–9
Dimensions (L × W × H)	15.5″ × 9.7″ × 7.2″ (393 × 246 × 181 mm)
Certifications	UL Listed, cUL Listed (UL 1081, CSA C22.2), Energy Star
Included Accessories	Flexible hose, adapters, reducer bushings
Installation Manual P/N	356360

🔌 Electrical Requirements

Electrical Spec	Requirement
Supply Voltage	115V or 230V (factory preset 230V)
Frequency	60 Hz
Phase	Single
Full Load Amps (115V)	9.0 A
Full Load Amps (230V)	4.5 A
Voltage Tolerance	±10% of rated voltage
Wire Size (up to 100 ft)	#12 AWG
Wire Size (over 100 ft)	#10 AWG
Bonding Conductor	#8 AWG solid copper minimum (#6 AWG in Canada)

⚠️ IMPORTANT:

All electrical work must be performed by a licensed or certified electrician in accordance with the National Electrical Code (NEC) and all applicable local codes and ordinances.

The pump is factory preset for 230V operation. To convert to 115V, slide the voltage selection switch above the terminal board to the 115V position. Never wire a 115V motor to a 230V line or vice versa — permanent motor damage will occur if wiring voltage does not match.

GFCI (Ground Fault Circuit Interrupter) protection is required. The pump must be connected to a GFCI-protected branch circuit. Test the GFCI routinely per manufacturer instructions.

A dedicated circuit is required — do not share with other appliances.

Bond the motor to the pool structure using #8 AWG solid copper conductor to all metal parts of the pool, electrical equipment, metal conduit, and metal piping within 5 ft of the pool walls.

🔗 Compatibility Guide

This Pump:

📍 Inlet: 1″ NPT (Female Pipe Thread), Top 📍 Outlet: 1″ NPT (Female Pipe Thread), Top 📍 Voltage: 115V/230V Dual (switchable) 📍 Motor: IEC 71 TEFC, IP44

Compatible Pressure-Side Pool Cleaners:

• ✅ Pentair Racer Pressure-Side Cleaner
• ✅ Pentair Letro Legend Platinum (LL105PM)
• ✅ Pentair Letro Legend 4-Wheel (LL105)
• ✅ Pentair Letro Legend 3-Wheel
• ✅ Pentair Letro Legend II (LX2000)
• ✅ Pentair Legend II (LX5000G)
• ✅ Pentair Letro Jet Vac (JV105)
• ✅ Pentair Sweep I & II (L79BL)
• ✅ Pentair Kreepy Krauly Legend (LL505G / LL505GG)
• ✅ Pentair Kreepy Krauly Platinum
• ✅ All pressure-side pool cleaners requiring a booster pump

Direct Replacement For:

Original Pump	Part Number
Pentair Letro Booster Pump	LA-MS05
Pentair Legacy Booster	61022

---

🛠️ Installation Requirements

Location:

Requirement	Specification
Surface	Firm, level — bolt to concrete pad recommended to reduce vibration
Distance from Pool Wall	Minimum 5 ft (1.5 m) from inside wall; 9.8 ft (3 m) in Canada
Distance from Heater	Minimum 3 ft (0.9 m) from heater outlet
Maximum Height Above Water	8 ft (2.4 m)
Maximum Depth Below Water	3 ft (0.9 m)
Rear Clearance	Minimum 12 in (0.3 m) from wall for ventilation and servicing
Ventilation	Well-ventilated location protected from excessive moisture
Hot Tub / Spa	Do NOT install within outer enclosure or beneath skirt

Plumbing:

Connection	Size
Inlet	1″ NPT
Outlet	1″ NPT
Minimum PVC Pipe	1″ (use larger diameter if suction run exceeds 5 ft)
Reducer Bushings	Included (1″ to 3/4″ white bushing for hose connection)
Hose Kit	Included — flexible hose with adapters

Installation Notes:

⚠️ This pump is NOT self-priming. It must only operate when the main filter pump is running. Never run the booster pump with the filter pump off.

⚠️ Connect the suction side of the booster pump after the filter to ensure a filtered water supply. Connect to the return line on the discharge side of the filter.

⚠️ The booster pump requires a minimum water flow of 20 GPM from the filtration system to avoid running dry.

⚠️ Do NOT connect the booster pump directly to a heater — heated water can damage the pump if the heater malfunctions. Install a tee after the filter to direct water to both the booster pump and heater separately.

⚠️ Slope suction pipe slightly upward toward the pump to avoid air locking.

⚠️ Support both suction and discharge pipes independently near the pump to avoid strain on connections.

⚠️ A separate automatic timer or manual switch is recommended. Set the booster pump to turn on at least 30 minutes after the filter pump starts and turn off at least 30 minutes before the filter pump shuts off.

---

⚙️ Maintenance Guide

Routine Maintenance:

Task	Frequency	Notes
Check for leaks	Monthly	Around connections, hoses, and drain plug
Inspect hose connections	Monthly	Verify adapter caps are tight and hoses have no kinks
Verify filter is clean	Before each use	Clogged filter reduces water supply and can damage mechanical seal
Check amperage	Annually	Should match nameplate rating (9.0A at 115V or 4.5A at 230V)
Inspect motor fan and guard	Quarterly	Ensure fan guard is not pushed against fan; keep clear of debris
Verify timer synchronization	Periodically	Filter pump must start before and stop after booster pump
Test GFCI	Routinely	Push test button to verify GFCI interrupts power; reset afterward

Warning Signs — Replace or Service Pump If:

• Unusual noise (grinding, loud vibration, or cavitation)
• Water leaking from mechanical seal
• Motor trips breaker repeatedly
• Reduced water flow or cleaner runs too slowly
• Motor overheating (wiring may be undersized or ventilation blocked)
• Fan guard pushed against fan (can be repositioned with hammer and screwdriver)

Winterizing:

Drain all water from the pump and piping when expecting freezing temperatures or when storing for extended periods. Cap inlet piping after draining to keep water out. Cover the motor to protect from rain, snow, and ice, but avoid airtight materials that trap moisture and corrode the motor. Freeze damage is not covered under warranty.

Startup After Winterizing:

If the pump fails to start after a shutdown period, disconnect power, insert a 1/4″ hex key into the center hole of the fan guard, and rotate the motor shaft to free the seal. Remove the hex key completely before reconnecting power.

Replacement Parts:

Part	Pentair Part Number
Hose Adapter Kit (2 reducer bushings, 4 adapters, 6 ft hose)	353020

---

🎯 Ideal Applications

Application	Suitability	Notes
💧 Pressure-side pool cleaner booster	✅ Yes	Primary application — powers all Pentair pressure-side cleaners and compatible brands
💧 Pool water circulation boost	✅ Yes	Increases system pressure and water flow for improved circulation
♨️ Hot tub / spa jet pump	❌ No	Not designed for hot tub jet applications; may be used with spas per Pentair guidelines only if so marked
♨️ Spa circulation pump	❌ No	Not a circulation pump
🛁 Whirlpool bath pump	❌ No	Not designed for bath applications

---

❓ Frequently Asked Questions

Q: What is the horsepower rating of this pump? A: The Pentair HydroBoost is rated at 0.8 THP (Total Horsepower) with a Weighted Energy Factor (WEF) of 0.62.

Q: Does this pump work with 115V and 230V? A: Yes. The pump is factory preset for 230V (4.5A) and includes a built-in voltage selection switch for easy conversion to 115V (9.0A). Slide the switch above the terminal board to change voltage. All electrical work must be performed by a licensed electrician. Never wire a 115V motor to a 230V line or vice versa.

Q: What does this pump replace? A: The Pentair HydroBoost 360526 directly replaces the Pentair LA-MS05 booster pump. It saves up to 25% on energy costs compared to conventional booster pumps.

Q: What pool cleaners is this compatible with? A: The HydroBoost is compatible with all pressure-side pool cleaners including Pentair Letro Legend, Letro Jet Vac, Pentair Racer, Pentair Kreepy Krauly Legend and Platinum, Pentair Sweep I & II, and other brands requiring a booster pump.

Q: Is this pump self-priming? A: No. The HydroBoost is a flooded suction pump and must only be operated when the main filter pump is running. The filter pump must provide a minimum of 20 GPM water flow. Never run the booster pump dry — this will damage the mechanical seal.

Q: What size are the connections? A: Both inlet and outlet ports are 1″ NPT (Female Pipe Thread) with top-style connections. This is larger than the 3/4″ ports found on many older booster pumps, which helps improve flow efficiency. Reducer bushings and hose adapters are included.

Q: What is the TEFC motor? A: TEFC stands for Totally Enclosed Fan-Cooled. This motor design seals internal components from moisture, dirt, and debris while using an external fan for cooling. This significantly reduces the risk of motor burnout compared to open-frame motors.

Q: Is this pump Energy Star certified? A: Yes. The Pentair HydroBoost is EPA Energy Star certified, saving up to 25% on energy costs compared to conventional booster pumps.

Q: What are the dimensions? A: The HydroBoost measures 15.5″ long × 9.7″ wide × 7.2″ high (393 × 246 × 181 mm). It is approximately one-third more compact than traditional booster pumps.

Q: What warranty is included? A: Pentair offers warranty coverage on the HydroBoost. Extended warranty is available when installed by a qualified installer. Contact Parts4Tubs or refer to the Pentair product documentation for full warranty terms.

Q: Do I need a GFCI breaker? A: Yes. GFCI protection is required by the National Electrical Code (NEC) for all pool equipment. The pump must be connected to a GFCI-protected branch circuit.

Q: Can I install this next to my pool heater? A: Install the booster pump at least 3 ft (0.9 m) from the heater outlet. Do NOT connect the booster pump directly to the heater — install a tee after the filter to separate water flow to the booster pump and heater independently.

🏆 Why Choose the Pentair HydroBoost 360526

✅ Energy Star Certified Efficiency – Saves up to 25% on energy costs with a WEF of 0.62 for reduced operating expenses

✅ TEFC Motor Protection – Totally Enclosed Fan-Cooled motor seals out moisture and debris to dramatically reduce motor burnout risk

✅ Premium 5-Stage Hydraulic Design – Delivers 50 PSI at 13.2 GPM for powerful, consistent pool cleaner performance

✅ Compact Design – One-third smaller footprint than traditional booster pumps for easy installation in tight spaces

✅ Whisper-Quiet Operation – Maximum 75 dB(A) noise level minimizes disruption during pool cleaning cycles

✅ Pentair Quality and Reliability – Backed by one of the most trusted names in pool and spa equipment worldwide

✅ Complete Installation Kit – Includes hose, adapters, and reducer bushings for quick installation or retrofit

✅ UL and cUL Listed – Tested and certified to UL 1081 and CSA C22.2 safety standards

🤝 Why Buy From Parts4Tubs

✅ US-based support for American customers

✅ Fast shipping across the United States

✅ Expert advice from pool and spa specialists

✅ Competitive pricing in USD

✅ Full warranty support

✅ Hassle-free returns

✅ Replacement hose kits and parts available

✅ Dedicated customer service team

💧 Summary

The Pentair HydroBoost 360526 is a 0.8 THP Energy Star certified booster pump featuring a TEFC motor, 5-stage hydraulic design delivering 50 PSI at 13.2 GPM, and dual voltage operation (115V/230V). With 1″ NPT connections, a compact footprint one-third smaller than traditional booster pumps, whisper-quiet 75 dB(A) operation, and IP44 protection, the HydroBoost replaces the Pentair LA-MS05 and powers all major pressure-side pool cleaners. UL/cUL listed, includes hose and adapter kit, and saves up to 25% on energy costs. Order today from Parts4Tubs for fast US shipping.

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.