Jandy JXI heater not working

[poolfl321]

I have a JXI that is 1.5 years old and is now not igniting. I sometimes hear it fire up and I can feel the heat from the blower for a few moments and then it turns off.

Other times, it does not ignite as shown in this Video here

The only error I have seen it display is "fault check IGN"

 

[ajw22]

Welcome to TFP.

We seem to be seeing a lot of that heater flame sensing (rectification) problems. Read Heater Flame Sensing - Further Reading for background information on it.

@setsailsoon just fought a big battle with his Jandy heater and we all learned a lot from that.

 

[setsailsoon]

Pool,

I had this exact same problem at about the same age on my Jandy Jxi. You get this error when something in the heater start sequence has reported an unsafe condition. This can be

• the pressure sensor that checks for flow
• the temperature sensors that check for high temp
• the pressure sensor on the back of the fan is indicating blocked air flow
• the stack temp fusible link that has failed from vent blockage or fire in the stack
• failure to detect flame

First thing to try is to reset power at the breaker. If you are still in warranty you should call your installer since you can void your warranty by trouble shooting yourself. If that doesn't matter to you then remove the top panel then very carefully wiggle the connections during the start sequence at each of the sensors mentioned above. In my case it was a bad connection at the air pressure sensor mounted to the plastic housing on the rear of the fan. I removed cleaned all the sensor contacts then replaced and coated with Corrosion Block. Never had this exact error again.

Let me know if this does not work for you. Next step is to bypass the sensors one at a time to see if you have a bad sensor. The air pressure sensor is a little tricky since it must read one way at start and then close. I can talk you through this if needed.

I hope this helps.

Chris

PS Be sure you actually do have good flow and don't have a plugged filter or closed valve that limits flow

 

[poolfl321]

Pool,

I had this exact same problem at about the same age on my Jandy Jxi. You get this error when something in the heater start sequence has reported an unsafe condition. This can be

• the pressure sensor that checks for flow
• the temperature sensors that check for high temp
• the pressure sensor on the back of the fan is indicating blocked air flow
• the stack temp fusible link that has failed from vent blockage or fire in the stack
• failure to detect flame

First thing to try is to reset power at the breaker. If you are still in warranty you should call your installer since you can void your warranty by trouble shooting yourself. If that doesn't matter to you then remove the top panel then very carefully wiggle the connections during the start sequence at each of the sensors mentioned above. In my case it was a bad connection at the air pressure sensor mounted to the plastic housing on the rear of the fan. I removed cleaned all the sensor contacts then replaced and coated with Corrosion Block. Never had this exact error again.

Let me know if this does not work for you. Next step is to bypass the sensors one at a time to see if you have a bad sensor. The air pressure sensor is a little tricky since it must read one way at start and then close. I can talk you through this if needed.

I hope this helps.

Chris

PS Be sure you actually do have good flow and don't have a plugged filter or closed valve that limits flow

Thanks so much for offering help! How did you determine which wires were for which sensor?

 

[poolfl321]

Are you able to point to which of these wires to try?

Also here is what the LEDS look like Video

 

[setsailsoon]

Pool,
*** :Edit: Whoops, forgot the image. Sorry!***

I neglected to welcome you to TFP earlier so Welcome!

I made a quick marked up of the photo circling in red the areas where several sensors are. The middle circle is the pressure sensor I referred to and it was the one that caused my connection problems. The pressure sensor that senses flow is located inside the panel that covers the PVC piping. The flue gas vent sensor is in the remaining circle near the large pipe that exits close to the black vent fitting.

I'll see if I can find a better diagram and send it next. In the meantime can you please look at the Fenwal ignition control module and confirm it blinks 3 times after the unit shuts down? If not how many times does it blink?

Thanks.

Chris

 

[setsailsoon]

Pool,

Here are a couple of images that may help. Here's the Fenwal ignition module, note the red light on the left edge:


Here's the water pressure switch:



Here are the high temperature sensors:

 

[setsailsoon]

Pool,

Here's another image below showing diagrammatically how the boards and module are interconnected to sensors. Importantly you can use this to track down the wires to the proper connectors.

Chris

 

[setsailsoon]

Pool,

In the video did it ever ignite a flame? I hear the blower but I don't hear ignition or was it already ignited?. The normal sequence after you turn on the heater is the temp setting is detected above the actual temp. Then the control board checks for hi/lo temp, water pressure, vent fire sensor, then it issues "call for heat" to the ignition control. Then the blower starts and the ignition module checks pressure senor. After 15 sec the igniter is turned on and you'll see a faint then strong orange glow through the igniter window. This is the preheat interval. Then you hear the gas valve open and ignition occurs. Before 7 seconds the ignition module must detect a minute (million's of an amp) flame-sense current through the ground circuit. If not, it shuts down. Is this complete cycle happening? Can you see a orange-red glow at the site glass on top of the burner box? The heater should try to ignite and sense flame 2 times then shut down with IGN Fault each time you try to start it. Is this happening or is the error code intermittent? Can you confirm the number of flashes that occur on the red light on the edge of the Fenwal ignition module? If not, how many times does it blink?

Thanks.

Chris

 

[poolfl321]

Are you able to point to which of these wires to try?

Also here is what the LEDS look like Video

Thanks so much for all the detail! As far as the red blinking light I took a video of it l, comes on about 30 seconds or so but remains blinking. Doesn't seem to stop until I try to run it again. Video

 

[poolfl321]

Pool,

In the video did it ever ignite a flame? I hear the blower but I don't hear ignition or was it already ignited?. The normal sequence after you turn on the heater is the temp setting is detected above the actual temp. Then the control board checks for hi/lo temp, water pressure, vent fire sensor, then it issues "call for heat" to the ignition control. Then the blower starts and the ignition module checks pressure senor. After 15 sec the igniter is turned on and you'll see a faint then strong orange glow through the igniter window. This is the preheat interval. Then you hear the gas valve open and ignition occurs. Before 7 seconds the ignition module must detect a minute (million's of an amp) flame-sense current through the ground circuit. If not, it shuts down. Is this complete cycle happening? Can you see a orange-red glow at the site glass on top of the burner box? The heater should try to ignite and sense flame 2 times then shut down with IGN Fault each time you try to start it. Is this happening or is the error code intermittent? Can you confirm the number of flashes that occur on the red light on the edge of the Fenwal ignition module? If not, how many times does it blink?

Thanks.

Chris

Chris

1. Where is the actual igniter window?
2. Can I unplug any of the sensors to bypass them?

 

[setsailsoon]

Pool,

Your ignition control is indicating the problem is the air pressure signal. Either the wires are not making good connection, the rubber tubes are not connected properly or cracked or the pressure sensor has failed. Please remove the two wires one-at-time then clean and replace the wire. Then try again. Also check the two rubber tubes to be sure they are fastened and not cracked.

Chris

 

[setsailsoon]

. Where is the actual igniter window?

Pool,

Here's your photo with a red arrow showing the window. It's a little obscured in the photo with this angle by the fan housing. The red light blinking 1 time indicates you are not getting a safe indication from the air switch. The switch is intended to show there's air flow through the fire box to prevent potential explosive level that can happen when insufficient air is flowing. Please see my previous message with things to check. This is not all that hard to fix.

Chris

 

[poolfl321]

Chris

Thanks so much for point those out. I tried again this morning and the first test of the morning I have Here. You can see it light up and this time you could hear it ignite then turn off.

The 2nd time it came on it did not show any flame before turning off.

3rd time showed the fire but I did not hear it ignite.

I looked at all wires, removed / cleaned. Tubes looked fine. Only the ground wires looked rough, I included a photo of those.

Do you believe there are any other things I could try or should I move to replacing the air sensor?

 

[setsailsoon]

Chris

Thanks so much for point those out. I tried again this morning and the first test of the morning I have Here. You can see it light up and this time you could hear it ignite then turn off.

The 2nd time it came on it did not show any flame before turning off.

3rd time showed the fire but I did not hear it ignite.

I looked at all wires, removed / cleaned. Tubes looked fine. Only the ground wires looked rough, I included a photo of those.

Do you believe there are any other things I could try or should I move to replacing the air sensor?

Pool,

Sounds more and more like a connection issue. They are often intermittent. Please check both ends of the wire connections. It takes only a tiny amount of debris or corrosion to interfere. It's extremely rare for this sensor to fail. Other ones fail much more often. Take the hose off and blow into it during the ignition cycle to see if you are getting flow. It takes almost nothing to activate the switch. If this works your switch is OK. Check for obstructions in the hose and in the air suction under the plastic cover (there are 2 screws that hold it on). Sometimes mud daubers fill it with mud and block flow. Last option would be replace the switch but I doubt it is the problem.

Chris

 

[poolfl321]

I tried blowing on the tube but no success. With the plastic cover, is that located on the top of the unit? Only found a metal cover

 

[setsailsoon]

Pool,

See the photo below. There is a red line pointing to the black plastic cap. Also I've shown a solid red dot at the end of the hose that you need to remove so you can blow into it. You don't have to put it in your mouth. The switch is very sensitive. Just blow into it from a 2 " away. Check continuity at the terminals to see if the switch opens or closes.

Chris

 

[poolfl321]

Hey Chris - I just wanted to thank you so much for your time explaining the possible issues. After trying all options it turned out the issue was a bad blower motor. A local company replaced it and now everything works! He said he has only seen this happen one other time with a unit this new.

 

[setsailsoon]

Pool,

Thanks so much for the followup. Often we don't get and never know the outcome. Most important is that we find out if there was something we can learn. These heaters seem to have a LOT of unlikely things that can cause failure... I actually thought my motor was bad recently but turned out to be the weird low current ground leak!

Glad you're back to enjoying the pool and thanks again for helping us(me) learn!

Chris