Jandy Pool Heater

[SaskMan]

Ah this pool is gonna be the end of me….

Have a Jandy LRZen250 natural gas heater.

Have not ever had any issues starting it other than I’ve had to replace a
Couple flame sensors.

This year I get the glow from the hot surface igniter. Then I hear the clicking sound. Glow goes away. And retries 3
Times until it locks out.

Brought a plumber friend over. We thought
It was the fenwall since the clicking sound is not coming from the valve, but was coming from the fenwall. We also tested the HSI and it was giving us resistance in that 16 range I believe. I finally got the Fenwall today. Installed it. Same issue. HSI glows and then nothing.
We did loosen off the gas supply directly before the gas valve and there is definitely gas there - we smelt it right away. So for some reason the gas valve isn’t opening.

Could the hot surface igniter not be getting hot enough to tell the gas valve to open? Also when we hear the clicking sound I can put my hand on the gas valve and it’s definitely not the gas valve that is clicking it’s the Fenwall. Shoukd step one be change the hot surface igniter. If that doesn’t work then change the gas valve?
Stuff is expensive. Fenwall cost be $300, new hot surface igniter is $200. And a new gas valve is $500. I don’t mind spending the money but all these suppliers won’t take returns once purchased. So like the Fenwall I’m stuck with it now.

Any direction would be appreciated!!!

 

[ajw22]

Check if you get 24V on the gas valve wires when the heater tries to start.

If you have 24V on the gas valve and you don’t hear the gas valve click and get gas then the gas valve is defective.

It does not look for a temperature at the HSI to open the gas valve.

The igniter is heated, then the gas valve is opened, then the Fenwal looks for flame sense to tell it to continue or shutdown.

 

[SaskMan]

I can try that again tomorrow but when we ordered the Fenwall we did try this and we weren’t getting 24 volt from the Fenwall to the gas valve. Which was another reason we thought it was the fenwall. But new fenwall installed. Does the same thing. Glow comes on. Glows bright. Then clicks from Fenwall and no ignition. Could the wires going from the fenwall to the valve be bad?

 

[SaskMan]

Check if you get 24V on the gas valve wires when the heater tries to start.

If you have 24V on the gas valve and you don’t hear the gas valve click and get gas then the gas valve is defective.

It does not look for a temperature at the HSI to open the gas valve.

The igniter is heated, then the gas valve is opened, then the Fenwal looks for flame sense to tell it to continue or shutdown.

So if I am not getting the 24 volts to the valve, what might it be?

 

[ajw22]

Post pics of the gas valve and insides of your heater.

@swamprat69 may be around to help.

 

[SaskMan]

Post pics of the gas valve and insides of your heater.

@swamprat69 may be around to help.

Post pics of the gas valve and insides of your heater.

@swamprat69 may be around to help.

 

[swamprat69]

16 ohms seem to be a bit low for a silicon carbide hot surface ignitor. Do you have the spiral type ignitor? From your symptoms it seems like you might be having a problem with the gas valve that might have caused a problem with the Fenwal ignition control. Try removing the 2 wires from the gas valve and measuring the resistance at the 2 gas vlave terminals that the wires were attached to. Also check the resistance from both terminals individually to a case ground such as the "GND" terminal on the Fenwal. It is possible that a stuck gas valve solenoid, a shorted gas valve solenoid winding or a solenoid winding shorted to ground killed the gas valve relay contacts in the Fenwal without blowing the 24V fuse. If this was the case, it might have done the same thing to the new Fenwal. Worry about the ignitor later, first try to determine what the problem is with the gas valve and Fenwal.

 

[SaskMan]

Thanks swamprat69.

I had the flat igniter style. But it blew so I order a spiral one. Should be here next week.

Seeing as I am just testing resistance I assume I don’t need the igniter installed for that. I will get this tested and report back what the resistance is.

 

[SaskMan]

16 ohms seem to be a bit low for a silicon carbide hot surface ignitor. Do you have the spiral type ignitor? From your symptoms it seems like you might be having a problem with the gas valve that might have caused a problem with the Fenwal ignition control. Try removing the 2 wires from the gas valve and measuring the resistance at the 2 gas vlave terminals that the wires were attached to. Also check the resistance from both terminals individually to a case ground such as the "GND" terminal on the Fenwal. It is possible that a stuck gas valve solenoid, a shorted gas valve solenoid winding or a solenoid winding shorted to ground killed the gas valve relay contacts in the Fenwal without blowing the 24V fuse. If this was the case, it might have done the same thing to the new Fenwal. Worry about the ignitor later, first try to determine what the problem is with the gas valve and Fenwal.

So I’ve done the ohms resistance testing. Nothing. I get no reading whatsoever when I measure resistance on the two gas valvle contacts together. Then also tried to touch one contact at a time while putting the other end of the multimeter on the fenwall ground. And again nothing. I’ve tried every setting on the resistance multimeter and nothing.i get nothing for resistance.
Is this a case of the user is an idiot or shouldn’t there be a reading here?

 

[SaskMan]

So I’ve done the ohms resistance testing. Nothing. I get no reading whatsoever when I measure resistance on the two gas valvle contacts together. Then also tried to touch one contact at a time while putting the other end of the multimeter on the fenwall ground. And again nothing. I’ve tried every setting on the resistance multimeter and nothing.i get nothing for resistance.
Is this a case of the user is an idiot or shouldn’t there be a reading here?

16 ohms seem to be a bit low for a silicon carbide hot surface ignitor. Do you have the spiral type ignitor? From your symptoms it seems like you might be having a problem with the gas valve that might have caused a problem with the Fenwal ignition control. Try removing the 2 wires from the gas valve and measuring the resistance at the 2 gas vlave terminals that the wires were attached to. Also check the resistance from both terminals individually to a case ground such as the "GND" terminal on the Fenwal. It is possible that a stuck gas valve solenoid, a shorted gas valve solenoid winding or a solenoid winding shorted to ground killed the gas valve relay contacts in the Fenwal without blowing the 24V fuse. If this was the case, it might have done the same thing to the new Fenwal. Worry about the ignitor later, first try to determine what the problem is with the gas valve and Fenwal.

I also found on this site a step by step trouble shooting guide. https://www.fwwebb.com/docs/gas/JandyPoolHeaterTroubleshootingGuides.pdf
Everything checks out
To step 12 and then it was getting dark and cold so i came in. I couldn’t verify the voltage to the HSI. But I assume since it would flow before it is fine. If everything else checks out I don’t understand why there wouldn’t be 24 Volts coming ignition module to gas valve.

 

[swamprat69]

0 ohms at the 2 gas valve terminals would mean that the gas valve solenoid coils are open and you would need a new gas valve. How are you measuring for 24V at the gas valve?? Do you realize that the gas valve is only powered with 24V during the ignition sequence for ~ 7 seconds. The ignition sequence is listed on the Fenwal. Main control asks for heat... blower runs for 15 seconds prepurge... ignitor heats up for 40 seconds... gas valve is powered for 7 seconds while Fenwal looks to see if flame is proven. You could check to see if the Fenwal is good by removing the 2 wires from the gas valve and check to see if you get 24V between the 2 wires during the ignition sequence after the prepurge and ignitor timings.

 

[SaskMan]

0 ohms at the 2 gas valve terminals would mean that the gas valve solenoid coils are open and you would need a new gas valve. How are you measuring for 24V at the gas valve?? Do you realize that the gas valve is only powered with 24V during the ignition sequence for ~ 7 seconds. The ignition sequence is listed on the Fenwal. Main control asks for heat... blower runs for 15 seconds prepurge... ignitor heats up for 40 seconds... gas valve is powered for 7 seconds while Fenwal looks to see if flame is proven. You could check to see if the Fenwal is good by removing the 2 wires from the gas valve and check to see if you get 24V between the 2 wires during the ignition sequence after the prepurge and ignitor timings.

I was measuring this by taking the two wires off the gas valve, letting the heater go through its ignition sequence and testing the two wires that normally would go on the gas valve. If I leave my multimeter on the two wires, let the furnace go through the ignition sequence, the HSI would heat up and glow, then the Fenwall should send 24 volts to the gas valve once the HSI heats up through those same two wires that my tester is on, and thats where I should see a 24 volt reading off the two wires that plug into the Gas Valve. Now Im not a mechanical guy but from porevious threads I thought thats what was a way to test and make sure the fenwall is sending 24 volts to the gas valve once the HSI heats up hot enough.
What I wanted to do is isolate the problem so I dont end up bying unnecessary $300 and $500 parts that I cant return. So now I have a new Fenwall, The new HSI should be here early next week. The only thing I havent replaced is the Gas Valve.

 

[SaskMan]

0 ohms at the 2 gas valve terminals would mean that the gas valve solenoid coils are open and you would need a new gas valve. How are you measuring for 24V at the gas valve?? Do you realize that the gas valve is only powered with 24V during the ignition sequence for ~ 7 seconds. The ignition sequence is listed on the Fenwal. Main control asks for heat... blower runs for 15 seconds prepurge... ignitor heats up for 40 seconds... gas valve is powered for 7 seconds while Fenwal looks to see if flame is proven. You could check to see if the Fenwal is good by removing the 2 wires from the gas valve and check to see if you get 24V between the 2 wires during the ignition sequence after the prepurge and ignitor timings.

I spent some time yesterday on this, and there is not 24 volts coming to the gas valve. As I mentioned earlier, the hot surface igniter broke so I have a new one on order, but nonetheless I did turn on the furnce, let it go through its ignition sequence. The 2 wires that go to the hot surface igniter definitely get power, but no power is being sent to the gas valve at all during the entire ignition sequence - I keep the multimeter on the 2 gas valve wires for a couple minutes during the ignition sequence and nothing.

The new hot surface igniter should be here tomorrow (Tuesday). I will put that in there and try again, but im doubtful it will work. And Im hesitant to drop $500 on a gas valve if it doesnt even seem to be getting power?

 

[swamprat69]

It seems that you have a problem with both the Fenwal ignition control and the gas valve. The Fenwal during the ignition sequence should put 24V to the gas valve during the ignition sequence after the ignitor warm up timing. The fact that you read 0 ohms at the gas valve terminals indicates that the gas valve solenoid coils are open and will not operate the gas valve when 24V is applied. It is possible that a problem with the gas valve caused the original symptoms and also damaged the replacement Fenwal. This is a good reason not to throw parts at a problem before thoroughly diagnosing the root cause of the problem.

 

[SaskMan]

Man this is so frustrating. Swamp rat I hear what you’re saying. Why would a faulty gas valve damage the Fenwal.
I have diagnosed the LRZ on the lrze troubleshooting guide someone posted. Everything checks out right up until step 13. There is no 24 volts to the gas valve. And there is no 24 volts at the VAL of the ignition control. The suggestion now is a new ignition control module which I already replaced.
So no I have replaced the circuit board, the Fenwal ignition control module. Flame sensor. And the hot surface igniter. The only thing I didn’t replace was the gas valve because it didn’t make sense to me that it for sure would be a gas valve issue if the fenwal wasn’t even putting out 24 volts to it.

The new error on get on the heater now is “fault check ign steps”.

 

[swamprat69]

Curious as to why you seem to have damaged Fenwal gas valve relay contacts and a damaged gas valve when the 24V fuse is supposed to blow in an excessive amp draw situation? You do have the correct 24V fuse inline after the transformer???

 

[SaskMan]

Curious as to why you seem to have damaged Fenwal gas valve relay contacts and a damaged gas valve when the 24V fuse is supposed to blow in an excessive amp draw situation? You do have the correct 24V fuse inline after the transformer???

I don’t know. I’m not even convinced this is the issue. I have put in a new fenwall. New circuit board. New hot surface igniter. New flame sensor. And it does the same thing now with all the new parts that it did before I even changed a single part. HSI glows hot. Then get a clicking sound from the Fenwal where the ground / igniter connect and the hot surface igniter extinguishes There is never ever a click at the gas valve.
Could the wiring harnesses and general wiring that runs between the circuit board and fenwall to the gas valve be damaged ?

 

[swamprat69]

There would never be a click at the gas valve if the solenoid coils are open and showing 0 resistance. You didn't answer question about fuse???

 

[swamprat69]

Also no click at gas valve if Fenwal is not applying 24V to the gas valve.

 

[SaskMan]

Curious as to why you seem to have damaged Fenwal gas valve relay contacts and a damaged gas valve when the 24V fuse is supposed to blow in an excessive amp draw situation? You do have the correct 24V fuse inline after the transformer???

If I have to pay a guy to come here to look at this fron the neighbouring city as
Ours doesn’t have a pool specialist, and then

There would never be a click at the gas valve if the solenoid coils are open and showing 0 resistance. You didn't answer question about fuse???

i have never changed a fuse at all. I looked at it yesterday and it looked fine.