How to Troubleshoot Jandy Jxi/Lxi Pool Heaters - (2024)

A Jandy pool heater is a lifesaver. If you own a pool, you naturally own a pool heater. They keep your water warm and fresh all year long. Naturally, they are heavily used during the winter. As a result, to keep flushing out hot water, they require consistent maintenance.

A Jandy pool heater quite easily provides endless gallons of water before they start slacking. A sudden power cut, the water feeling too hot or not warm enough, a faulty water pressure switch, and soon you’re left wondering what to do.

A Jandy pool heater is made up of various components like switches and valves that can stop working. Various issues may arise with your heater. Let’s take a detailed look at some of the most common issues to troubleshoot with a Jandy heat pump.

Issues to Look Out For

Pump Not Functioning

When the heater is not operating at all, it could be because of numerous causes. Sometimes there’s no power connection, the pump has malfunctioned, the wiring isn’t right, or, like a smartphone, the clock settings aren’t synchronized with the real-time.

How to Fix:

You can take a couple of steps to ensure the heater works again.

• Check with the circuit breakers and the power board to ensure it’s not a simple power outage.
• Inspect the wiring using pliers and a multimeter.
• Get a new heater altogether.
• Synchronize the clock in real-time.

Faulty Ignition

A faulty ignition is perhaps the most infamous issue that recurs with Jandy pool heaters. Whether your Jandy turns on and off abruptly, ignites slowly, or has aflame with a short yellow streak that then goes out, the pool will not feel the same and will require maintenance.

Malfunctioning combustion could result from the wrong gas being installed, a lean or rich air and fuel mixture that can cause a low supply of pressure, a high supply pressure, or too much or too little combustion air in the system.

How to Fix:

Let’s look at various approaches to fix faulty combustion.

• Firstly, check that the gas supply installed matches the gas type of the Jandy heater.
• Inspect the gas supply inlet pressure.

For Natural Gas:

Minimum 4.0 W.C. to Maximum 10.5 W.C.

For Propane:

Minimum 4.0 W.C. to Maximum 14 W.C.

• If you own a digital manometer, use it to check that the offset pressure is -0.2 in W.C. and adjust as necessary.
• Use the digital manometer to obtain a differential from the blower throat and the gas valve port. The differential value obtained must match the configuration of the Jandy heater size.
• Inspect the blower inlet grill for any damage or change.

Other causes may include:

• The gas meter is too small or the line from the meter to the heater is too small.

Inadequate Heat

Whether your heater takes more time to heat up or doesn’t maintain the set temperature consistently, or the temperature rise is painstakingly slow, there are a few causes behind inadequate heat.

Check to see:

1. if the heater size is inappropriate for the pool.
2. if the heater is plumbed from the back.
3. if the filter pump is not running for the time period necessary.
4. if the thermal regulator valve (TRV) is permanently open or opening too soon.

How to Fix:

• If the heater size is inappropriate, replace it with the appropriate size and output.
• Replace the thermal regulator valve.
• Install the filter pump plumbing accurately.

Heater Making Noises

Generally when the water flow through the heater is minimal or inadequate or when the thermal regulator valve stops working, you’ll hear knocks and loud noises coming from the heater.

How to Fix:

• Inspect if the valve system is closed or if there is any damage to it inside the equipment.
• Check whether the variable speed pump is set too low.
• Check for damage to the internal bypass.
• A dirty filter can also cause the heater to make noises.

Igniter Works But Heater Does Not

If the igniter lights and the heater doesn’t work, it could be due to one of the following causes:

• Gas valve turned OFF
• Air in the gas line
• No power connection to the gas valve
• Gas pressure is low
• Burner throat exudes high pressure
• Total gas valve failure

How to Fix:

• Turn the gas valve ON if it’s turned OFF.
• Get the air out of the gas line by altering the ignition sequence.
• Check the power board to ensure connection to the gas valve.
• Check the supply pressure to ensure the pipe size is accurate.
• Get a new gas valve installed.

Error Codes on Display Monitor

Check Flow

When this error code shows up on the monitor, the probable causes are:

• Pump malfunction
• Inadequate pump pressure
• Faulty pressure switch
• Variable speed pump is set below the requirement

How to Fix:

• Check the power board, circuit breakers, and wirings. Synchronize the clock with the current time.
• Clean the filter or basket of any blockages and inspect the valve position in the plumbing.
• Check the pressure switch and get a replacement if needed.
• If the variable speed pump is set too low, readjust it accordingly.

Check IGN Control

An ignition problem could be a cause for concern and usually has numerous causes:

• Air pressure switch tubing is damaged, disconnected, or interfered with
• Fan malfunctioning or not working at all
• Airflow is restricted somewhere in the pathway
• Low gas supply pressure
• Broken igniter
• Burner has no flame

How to Fix:

• Check and replace the air tubes if necessary.
• Inspect the faulty fan and replace it if necessary.
• Inspect the wirings carefully. Look for loose connections with the igniter, gas valve, and ignition.
• Check to see if the heater has proper ventilation and no blockages.’

Fault – Pump

This error code shows up when the heater system is in Maintain Temp mode. This means the filter pump is switched off and therefore doesn’t require any service.

Fault – High Flue Temperature

A high flue temperature error code indicates an issue with the flue temperature limit. To fix this issue, look for loose wire connections and replace the flue sensor if necessary.

Fault – High Limit

When the heater’s water temperature exceeds the internal limit or the limit switch itself malfunctions, this error code is displayed on the monitor.

Fault – Display Monitor Error Code: Check Aux Monitor

First, turn off the heater. Then press and hold the ‘menu,’ ‘spa,’ and ‘pool’ buttons together until the monitor displays a clear latch error code. Press the menu button to ‘Ok’ it and you can run the tub again.

How to Fix:

• Check the vent for any damage or blockages.
• Check the vent pipes for any bird, insect, or rodent presence that could cause obstructions.
• Replace the limit switch.

FAQs

What does ‘FAULT – HIGH WATER TEMP’ mean?

This error code indicates that your pool heater has reached the maximum temperature possible or above and that it is risky for anyone to be exposed to the water now.

What does an LED triple flash mean on my Jandy pool heater?

A triple flash on the display monitor means that there have been three unsuccessful attempts to fire the ignition and that it is now in ‘Ignition lockout’ mode.

What tools and equipment do I need to have before troubleshooting a Jandy pool heater?

To successfully troubleshoot all kinds of pool heater issues, you will need a flathead screwdriver, safety eyewear, a Phillips screwdriver, a pipe wrench, an adjustable wrench, a pair of gloves, a 3/16” Hex key, channel locks, a digital differential manometer, a tape measure, a voltage meter, a PVC pipe cutter, and a power drill.

Are flue gases harmful to my surroundings?

Irregular maintenance and faulty installation can result in nausea and asphyxiation from the carbon monoxide found in flue gases, resulting in severe injury or death. If you’re unsure of the issues, always ring up a professional to do it for you.

Are my medical conditions an issue for swimming in the hot tub?

If you are a diabetic or have a medical history of cardiac diseases and blood pressure problems, you should consult with a medical professional before using your pool or hot tub.

How much ventilation does a Jandy pool heater need?

A Jandy pool heater ideally requires two openings where it’s installed for adequate ventilation, usually maintaining a 12-inch gap above the floor for one opening and another 12-inch gap from the ceiling. The reason two vents are necessary is that the vented air comes internally; therefore, the heater must be located in a place where it is connected to the internal ventilation space inside.

How do I clean the filter?

• Before opening the filter, blow away any debris from the outside area.
• Ideally, switch off the main power.
• To make sure water isn’t wasted while you’re cleaning the filter, shut off the primary drainage in the bottom.
• You’ll find the air release valve on top of the filter; turn it to open.
• You’ll find the drain at the bottom of the filter; allow excess water to flush out.
• Take off the steel band to locate the cartridges beneath the dome.
• With a water hose, clean all the disassembled pieces of equipment.
• Reinstall all the parts and you’re done!

Conclusion

A pool heater is a necessity during the winter and even across all seasons for people living in colder regions. Jandy pool heaters are a marvel, as they last a long time and do an excellent job of consistently keeping your pool warm and cozy. Regular maintenance and knowing the ins and outs yourself will ensure the heaters give you their best performance, time and again. Learning how to troubleshoot these common issues will make your pool time more enjoyable.