Jandy Lt Heater Failure

[hep]

My heater basically quit working completely. After a bit of dilly-dallying, I got down to business and went through the exact step by step circuit troubleshooting in the manual with a volt meter.

Transformer, OK

Fuse, OK

pressure switch, OK

Next up is the limit switch test, which basically says if there is no voltage coming out of the control panel to the 150 limit switch (test point 11 on the wiring diagram), then either the entire control panel, or the 10 pin harness needs to be replaced. A harness is something that would generally show some kind of visible failure like a burnt, pinched, etc. wire and I found none. The controller itself is a circuit board, which is of course not as easy to "see" a failure.

My questions are these:

1. can anyone comment on if a controller failure is common or likely?

2. Have I followed the correct path of troubleshooting?

3. Any other tests that arent in my manual to verify that the controller is in fact the culprit?

The followed the troubleshooting sequence to the letter and it points straight to the controller, but I want to be sure before I drop $600 on a non-returnable part

Any help will be greatly appreciated.

[ps558]

My heater basically quit working completely. After a bit of dilly-dallying, I got down to business and went through the exact step by step circuit troubleshooting in the manual with a volt meter.

Transformer, OK

Fuse, OK

pressure switch, OK

Next up is the limit switch test, which basically says if there is no voltage coming out of the control panel to the 150 limit switch (test point 11 on the wiring diagram), then either the entire control panel, or the 10 pin harness needs to be replaced. A harness is something that would generally show some kind of visible failure like a burnt, pinched, etc. wire and I found none. The controller itself is a circuit board, which is of course not as easy to "see" a failure.

My questions are these:

1. can anyone comment on if a controller failure is common or likely?

2. Have I followed the correct path of troubleshooting?

3. Any other tests that arent in my manual to verify that the controller is in fact the culprit?

The followed the troubleshooting sequence to the letter and it points straight to the controller, but I want to be sure before I drop $600 on a non-returnable part

Any help will be greatly appreciated.

The one hi limit can go it is on the right side up top near the exhaust fan port. I can't remember off hand if it has a red reset button in the middle or not. One other thing to try is to jump out hi limits, pres sw etc one at a time and see if the heater fires.

[hep]

My heater basically quit working completely. After a bit of dilly-dallying, I got down to business and went through the exact step by step circuit troubleshooting in the manual with a volt meter.

Transformer, OK

Fuse, OK

pressure switch, OK

Next up is the limit switch test, which basically says if there is no voltage coming out of the control panel to the 150 limit switch (test point 11 on the wiring diagram), then either the entire control panel, or the 10 pin harness needs to be replaced. A harness is something that would generally show some kind of visible failure like a burnt, pinched, etc. wire and I found none. The controller itself is a circuit board, which is of course not as easy to "see" a failure.

My questions are these:

1. can anyone comment on if a controller failure is common or likely?

2. Have I followed the correct path of troubleshooting?

3. Any other tests that arent in my manual to verify that the controller is in fact the culprit?

The followed the troubleshooting sequence to the letter and it points straight to the controller, but I want to be sure before I drop $600 on a non-returnable part

Any help will be greatly appreciated.

The one hi limit can go it is on the right side up top near the exhaust fan port. I can't remember off hand if it has a red reset button in the middle or not. One other thing to try is to jump out hi limits, pres sw etc one at a time and see if the heater fires.

The problem is that there is no voltage to jump across the limit switches. Voltage in the limit switch circuit is supposed to travel FROM the controller, to the input of the 150 limit switch, output of the 150, input of the 135, output of the 135, then back to the controller.

I have no voltage coming out of the controller.

Sounds like i'm answering my own question, it's just not what I want to hear...

[AquaTechPool]

you said it. the genreal rule is " the problem lies, where the power dies". so if your sure you have proper voltage coming into the controller, but do not have it going out, then sounds like you have nailed it down.

[hep]

I just love it when a plan comes together. Unfortunately, this is not one of those times!...

Replaced the control panel and still nothing. The only thing that happens is the led's on the panel do their little test sequence. from there I get no fan pre-warm up thing, no light, no nuthin'. I also do not have any fault lights on the front panel and no fault code where the blinking led would show under the service panel.

I have used a multi meter to confirm that the transformer, fuse and pressure switch are all functioning correctly. There is no voltage leaving the controller on it's way to the limit switches, which is the next diagnostic in the sequence.

Anyone else have any ideas?

Anyone here a service tech in so cal that needs some work?

I also saw the diagnostic flow chart, but that all seems to be based on fault lights or codes, which I have none. Am I missing anything there?

Thanks again.

[Pool Clown]

Do you have any automation ? If you're sure you are getting voltage into but not out of the board, it kinda sounds like it's not getting a call for heat, call for heat comes before power leaves the board. could be like a loose wire, or a control wire open, firemans switch ?

[hep]

I do have an aqualink RS.

With no fault codes, I thought maybe the senor?

A "call for heat" sounds exactly like what I'm not getting. I'll start reading that manual and see what I find.

[hep]

under diagnostics on my aqualink, time calibration says "-24 2". Is that a problem? I found noting in the manual on calibrating time.

[hep]

After figuring out that the jandy RS remote signal comes through the firemans switch block, I simply disconnected it and ran a loop. Sure enough, the heater functions fine when turned on manually.

My aqualink manual has no real diagnostic info, where can I get some?

The time calibration says -24 5 now, doesn't seem right. How do I calibrate?

Thanks again.

At least I can use my spa now,I understand that I should run the pump a few minutes after I turn off the spa though.

[hep]

found an aqualink troubleshooting guide. It sys if the heater doesn't fire, check the temp sensor. The display on the device does show an accurate temp, can it still be sending an incorrect signal to the heater?

[Pool Clown]

It's not a signal really. It, (the Jandy) closes a switch and completes the safety circuit on the heater. I would look more towards a wire that has come loose between the aqua link and the heater. First look for any splices, That's where I find the majority of opens. If it isn't spliced, great, now look at the ends make sure those contacts are good. Probably wire nuts at the heater and connected to a bus labeled "low voltage heater" pin 1 & 2 at the controller. I've had mice chew this wire so that's not out of the ordinary.

If that don't work, I got more.

[hep]

I am now pretty well stumped. later in the same day that the heater fired up after I disconnected the RS remote, I hit the heater button and nothing, I'm right back to the original symptom. Voltage up to the controller, no voltage on the way to the limit switches. No idea why it decided to fire up that one time.

[Pool Clown]

My Bad, Didn't see you had a LT. Eyes start to go around 40... Ok, first do this, there may be a led on the fenwal. Try to fire the heater and when It doesn't start, see if that led is flashing if so, count the number of flashes. Next, See if the fan comes on. Find the Fenwal Ign controller. Find the Black wire and the Gray wire labeled F1 and F2 and connect them together. Fan should come on no matter what.

[hep]

Still trying to figure this thing out. Since there's no fault codes, I'm wondering if the temp sensor might be faulty. Anyone know what the range of resistance should be? I measured about 1.8 ohms with a water temp of approx. 70 deg.

Anything else that would cause no call for heat?

Thanks.

Pool Clown, you have an email.

[Pool Clown]

My Jandy book says 70 should give you 11.893K That may be it!

If not...

The Fenwal switches the fan. If you know the fan runs, May be Fenwal, but i don't think I've ever run into a Fenwal that was intermittent. I'm still thinking wire somewhere. Especially a ground wire. If you can get your finger on the relay that's on the thermostat board, you should be able feel it click when you raise the thermostat (call for heat). That sends voltage out to the hi-limits.

Still no e-mail...

P.S. Is the heater a low-nox?

[hep]

thanks again, ive been out in the desert playing all week. I'm more of a nuts and bolts guy, tell me if i;m reading the multimeter right. I set the switch on the arrow with a + sort of attached looking symbol and it reads like 1.764.

That is out of range? with that reading, does my heater think the water is really cold or really hot? Hot, i hope...

can I trick this circuit to verify?

I've been all over this thing looking for loose wires and bad grounds, I'm pretty sure there are none.

Yes, it's a low nox.

My Jandy book says 70 should give you 11.893K That may be it!

If not...

The Fenwal switches the fan. If you know the fan runs, May be Fenwal, but i don't think I've ever run into a Fenwal that was intermittent. I'm still thinking wire somewhere. Especially a ground wire. If you can get your finger on the relay that's on the thermostat board, you should be able feel it click when you raise the thermostat (call for heat). That sends voltage out to the hi-limits.

Still no e-mail...

P.S. Is the heater a low-nox?

[Pool Clown]

Shoot! Low nox is different. Different flow chart anyway. Let me get my book. Your looking for a value between 5K and 19K ohms, so set your meter to 20K ohms and depending on the temp, you should be somewhere between those two values. If you get anything but that, replace the temp sens. If the value is within, Why don't you pm me and I'll send you the flow chart(s).

[hep]

OK, with my meter set on 20k, I get a reading of 2.25. That means a value of 40.5 ohms right?

[Pool Clown]

No, 2.25 K ohms. I'm too lazy to do the math, It's telling your unit it's about 118 degrees, give or take. Go get a temp sensor.

[hep]

10-4, it's on the way.

[hep]

SUCCESS!... Sort of.

The temp sensor did the trick, the heater fires up, but now will not stay lit. (

Here's the scenario:

1. Turn on

2. Purge/fan high

3. Igniter is visible through window/fan on low

4. Burner lights/fan on low (about 15 seconds)

5. fan turns on high and gas shuts off at the same instant

3 to 5 repeats a few times then I get a fan pressure fault light on the control panel.

One thing that is unusual is that during #4, steam is coming out of the fan. We did just have some rain.

Any ideas?

Thanks for the help so far.

[Pool Clown]

Hmmm. Following taken from: Jandy L0897 Rev B 9/05

Error Codes: Air flow switch- Insufficient vacuum to close the air pressure switch. Make certain fan is running. Check the air hoses from the fan to the Air pressure switch for kinks or holes. IF THE FAN NEVER SWITCHES TO HIGH SPEED, REPLACE THE IGNITION CONTROL BOX.

[grandee1]

I’m all for figuring out problems and many times can, but after a couple days I usually throw my hands up and call in the pros. You have been troubleshooting this over month. You may want to call in a tech.

[hep]

Well, after removing the top of the unit to check the blower switch hose and giving everything one last once-over, I found another problem. the small passage with the blower heat switch at the end was plugged up with wet leaves. This must have caused some kind of fault because after cleaning it out, the heater is now running fine!

Big thanks to everyone for the help, except grandee1 of course for suggesting I give up! (just kidding) Believe me, I had thrown up my hands more than once, only to find what I thought was another reasonable solution.

I have heard too many stories of so-called experts with mis diagnosed problems to give up. Even though I bought a couple extra parts than I needed, I'm glad I worked my way through it, I'll be better educated if/when I have another problem.

Thanks again.

[Pool Clown]

Actually grandee1, I had been helping hep only since 11/15, less than 3 weeks. If you want to get technical, only seven posts in as many days. If hep and I had no life and we just sat in front of our computers all day, we would have been able to solve this problem in one afternoon. So this hardly took a long time, considering. I don't know what you do for a living but if you don't tele-commute, try diagnosing a problem off site with limited info (not seeing with your own eyes). hep's problem had multiple problems that lengthened the diagnosing process.