JXi Pool & Spa Heater

An Ultra-Compact and Energy-Efficient Gas Pool Heater

The JXi™ heater sets the standard in pool and spa heating with unsurpassed energy-efficiency and optional cost-saving Integrated Bypass technology that diverts water flow away from the heater when there is no call for heat. Boasting an 84% thermal efficiency rating and a low-NOx design, the JXi is available in both natural and propane gas models. The JXi also features advanced automation compatibility with AquaLink® systems and iAquaLink™ control, for anytime, anywhere convenience, and an ultra-compact, lightweight design, that allows for faster and easier installation—making it a top choice for pool professionals and pool owners everywhere.

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  • Energy-Efficient Heating - 84% thermal efficiency rating and low-NOx design surpasses strict DOE Energy Efficiency requirements.
  • Automation-Ready - Compatible with AquaLink® automation systems for anytime, anywhere control from your mobile device using the iAquaLink™ app.
  • 5-Year Heat Exchanger Warranty - JXi heaters with VersaFlo factory installed receive an industry leading 5-Year standard warranty on the heat exchanger.
  • Heat When You Want. Save When You Don’t. - The heater is typically only used 3.5% of average annual pump runtime, the other 96.5% of the time the heat exchanger can be bypassed
  • Save Even More with VersaFlo Integrated Bypass - Variable-speed pumps can be run at a lower speed when bypassing the heater, saving up to $350 per year in electricity costs***
  • Ultra-Compact Lightweight Design - Easy to store, transport, and install, JXi easily fits on a 2’ x 2’ pad and is 38% lighter with a 28% smaller footprint.
  • Best Retrofit Option - Plumbing flexibility for quick Mastertemp® and Max-E Therm® replacement that requires no plumbing adjustments.
  • Flexible Installation - Top can be easily removed for increased accessibility and rotated 180 degrees so you never need to rotate headers. Also includes a flip up electrical panel for convenient setup and service.
  • Versa Plumb® -Ready - Installation in the Versa Plumb system*(standard on all models) reduces plumbing costs and increases hydraulic efficiency, all using the smallest footprint available.††

*Not available with VersaFlo Integrated Bypass technology
**VersaFlo Integrated bypass is available factory-installed on select models or can easily be added to any JXi on site. See JXIVFKIT installation manual for more details.
***Versus similar system without VersaFlo. VersaFlo not available on ASME certified models.
Compared to major competitor models.
††Sweep elbow included in all JXi models

ASME Certified Models* Now Available

JXi™ models are available with robust heat exchanger tubes and corrosion resistant bronze headers to meet the high stresses of commercial installations.

Jandy JXi ASME Heater bronze headers
Jandy JXi Heater VersaFlo Kit
VersaFlo Integrated Bypass Technology

The JXi™ with VersaFlo is the first and only swimming pool heater that automatically directs the flow of water through the heat exchanger when heat is needed and around the heater when heating is not needed — allowing you to save money on the filtration pump electric bill.**


Frequently asked questions

For the last 20 years, Zodiac has been using a patented technology associating polyamides and titanium, both of which are totally free from the effects of corrosion. Today over 120,000 appliances have been installed without any corrosion defects. If a salt water chlorination method is being used, it is important to install a check valve between the heater outlet and the salt water chlorinator, to prevent high concentrations of chlorinated water from back siphoning into the heater.
No, it is perfectly possible to heat an "open air" pool without a cover or a shelter. The power and fuel requirements is similar to heating a house with the windows open! This is why we recommend the use of an insulating cover to limit heat loss to the open air when the pool is being heated. A covered or sheltered pool will reduce the amount of fuel needed and reduce the operating cost. Example: A 400 square foot pool in Tampa, heated to 82F year round could save 50% on the heating bill just by keeping the pool covered for 20 hours a day. Interested in getting a cover for your pool to save money? Check out our Coverpool products www.coverpools.com
1. Look for obstruction or closed valve in system. 2. Check for damaged internal bypass. 3. Variable-speed pump set too low. 4. Dirty filter or baskets.
1. Flip the switch to “on” position. 2. Cycle ignition sequence until air is out of the gas line. 3. Replace gas valve. 4. Check controls for proper operation. 5. Check supply pressure.
1. Heater is condensing. Flue product moisture will condense at the start-up until the heater water temperature reaches the normal operating conditions. 2. Faulty or broken Thermal Flow Regulator. 3. Correct the plumbing. 4. TRV failure.
1. Gas meter too small. 2. Gas line from meter to heater too small. 3. Correct gas supply pressure to 4.0" W.C. 4. Replace with heater of higher input. 5. Check blower inlet grill for obstruction.
1. Check circuit breakers and power source. 2. Replace the pump. 3. Recheck wiring. 4. Check time clock setting.
1. Make sure the gas supply matches the gas type indicated on the rating plate. 2. Correct gas supply pressure to 4.0" W.C. 3. Increase offset gas pressure. Rotate adjustment screw clockwise. 4. Correct gas supply pressure to 4.0" W.C 5. Decrease offset gas pressure. Rotate adjustment screw counter-clockwise. 6. Check offset pressure is set to —0.2” W.C. If this is set properly, connect manometer to blower throat and gas valve port to obtain differential. Make sure the differential value falls within the specified range for the heater size (see Table TBD in the owner's manual).