Laars Lite Pool Heater won't keep running

Jun 9, 2013
2
We have a Laars Lite gas pool heater with electronic ignition. Currently the unit will start up and will run fine for 5-10 mins, and then it will shut off. It clicks on start up, but there is no additional clicking after it gets going. Once it shuts down, if I turn it off and then back on, it fires up and then shuts down immediately. Any ideas on what could be causing it to shut down? The unit has a brand new control board, and there is no glow after it lights, so I am assuming the flame sensor is fine. Thanks in advance for any suggestions.
 
It is a Teledyne Lars lite LLD pool heater, approx 10 years old. I am unable to post pics (says they are not compatible?) As of right now, the heater clicks and tries to start, but no ignition. This is after I made sure all connections were good and clean.
 
I'm having the same problem. I've tried bypassing all the sensors and thermostats and it still happens. Is there some kind of circuit that's not on the schematic that could cause this behavior. Maybe something that detects if there is a flame or not?

Thanks!
 
See my post in this forum - you can find it easily, of a few days ago - it's a related problem, also with a Laars Lite LLD (Propane - tho' the natural gas version has all the same components, with just a couple add-on parts different on the gas valve). I've reached a point by troubleshooting that I believe my issue is the valve itself. There is a way to test the gas pressure entering and exiting the valve - too complicated to explain here - and it does not appear to open although it does click when the HSI (Hot Surface Igniter - which is also the sensor for flame presence!) gets up to max temperature. I know this because after detaching it from the gas pipe I can see through the screen and when I reattach the wires and start the circulation pump and turn on the heater and the HSI glows and the valve clicks (you can feel the electronic "click" in your hand), I can see through the screen that the mechanical valve (the bottom half) does not open! So I've ordered a new Honeywell valve and this week I'll install it. I'm confident this will work. My point is you should troubleshoot this valve. My heater is 20 yrs old but the stamp on my valve says it was made in '97. So it was obviously replaced once before. I've had my heater for only 2 yrs and I've replaced MANY components. By the way, this valve is priced on various internet sites from $150 to $350! So shop around for any parts.
NOTE: Also, parts websites also show a "flame sensor rectification kit" - my model does not have this part. It turns out that Laars once had a problem on some sets of this model where the HSI was not sensing the flame, so they came up with this fix. Thus the name "rectification kit". Perhaps some problems could be related to this and you need that kit. (I eliminated that in my case by methodical troubleshooting.)
PS: I see many times people here don't post what their problem resolution was. That is not helpful to teach the rest of us!! Please tell us!!!!
 
Also, I just noticed DAnpic is one of the helpful posters here. Dan helped me too - thanks again, Dan!
And I should add: Techyspice, your problem is probably fixed by now. WHAT WAS THE FIX???? I'm guessing it was the pressure sensor. BVS: this could be your problem too - and that would be good, as it's a quick and easy and low cost part to replace.
 
jjrepko said:
See my post in this forum - you can find it easily, of a few days ago - it's a related problem, also with a Laars Lite LLD (Propane - tho' the natural gas version has all the same components, with just a couple add-on parts different on the gas valve). I've reached a point by troubleshooting that I believe my issue is the valve itself. There is a way to test the gas pressure entering and exiting the valve - too complicated to explain here - and it does not appear to open although it does click when the HSI (Hot Surface Igniter - which is also the sensor for flame presence!) gets up to max temperature. I know this because after detaching it from the gas pipe I can see through the screen and when I reattach the wires and start the circulation pump and turn on the heater and the HSI glows and the valve clicks (you can feel the electronic "click" in your hand), I can see through the screen that the mechanical valve (the bottom half) does not open! So I've ordered a new Honeywell valve and this week I'll install it. I'm confident this will work. My point is you should troubleshoot this valve. My heater is 20 yrs old but the stamp on my valve says it was made in '97. So it was obviously replaced once before. I've had my heater for only 2 yrs and I've replaced MANY components. By the way, this valve is priced on various internet sites from $150 to $350! So shop around for any parts.
NOTE: Also, parts websites also show a "flame sensor rectification kit" - my model does not have this part. It turns out that Laars once had a problem on some sets of this model where the HSI was not sensing the flame, so they came up with this fix. Thus the name "rectification kit". Perhaps some problems could be related to this and you need that kit. (I eliminated that in my case by methodical troubleshooting.)
PS: I see many times people here don't post what their problem resolution was. That is not helpful to teach the rest of us!! Please tell us!!!!

Did you check to see if you had the correct voltage going to the valve? Sometimes they will click but there isn't enough voltage to actually cause the valve to open.
 
Thanks again, Paul - didn't think of that.
My voltage tester doesnt' show if there is 24 volts - it's only a circuit tester. If the replacement unit doesn't work I'll get the proper meter and check. (Luckily the supplier of my new valve offers 14 days to return it!)
 
You can pick up a low $ volt/ohm meter at most any big box store for $10-$20. For most homeowners they will be more than enough to test out things like this.

Gas valves are simple machines inside. There are actually two valves inside of them that have to open at the same time to work. This is a redundancy that is built in to prevent a runaway problem should one of them stick open. It is possible that one of the two may be stuck. Tapping on the side may free it. As PS0303 also mentioned, it could be a weak voltage signal not giving the solenoid enough power
 

Enjoying this content?

Support TFP with a donation.

Give Support
Still waiting for the part (gas valve) in the meantime I did the voltage check and there is definitely 24ACV coming off the wires that connect to the valve (30V in fact). So it seems to confirm its the valve is faulty. Turns out my heater and the valve were manufactured in 1997. The valve might only be sticking, but regardless, it is not working. I'll let you know, my kind advisers, when I install the valve which should arrive today or tmrw.
 
No luck! The new valve installation did not do it. Dang. I'm out of ideas. Paul, Dan - any ideas?
Again, when the HST is glowing bright orange for like 10 sec., there's a click and the wires to the valve show 30 VAC on my meter for about 6-7 seconds, but no ignition and another click and the voltage drops to 0 as the HST cools off.
I'm fairly ignorant re elec circuitry, but seems to me the gas valve getting that electricity is the final step in the ignition process. Gas pressure is definitely on the intake side. Spiders or other are not the prob, as I cleaned out everything when I had the burner assembly out to change the valve. This is a true mystery.
 
Re: Laars Lite Pool Heater won't keep running -SOLVED!

The new valve from Honeywell came with some extra parts. One was i conversion kit (just a spring, really) to change it from natural gas to propane. The other was a "wire harness" - really a simple connector. I originally installed the new valve without this connector - just connected the wires the same way they'd been on the original valve. But when I added the new connector it worked !!!
Thanks again, Dan and Paul!
 
jjrepko said:
No luck! The new valve installation did not do it. ****. I'm out of ideas. Paul, Dan - any ideas?
Again, when the HST is glowing bright orange for like 10 sec., there's a click and the wires to the valve show 30 VAC on my meter for about 6-7 seconds, but no ignition and another click and the voltage drops to 0 as the HST cools off.
I'm fairly ignorant re elec circuitry, but seems to me the gas valve getting that electricity is the final step in the ignition process. Gas pressure is definitely on the intake side. Spiders or other are not the prob, as I cleaned out everything when I had the burner assembly out to change the valve. This is a true mystery.

If you are getting a glowing HSI, a click, and 30V at the valve, you either have the gas valve closed (on the valve), the supply valve closed, or something is going on with your gas service. And oh yea, your brand new valve may be dead (seen that). Have you verified that you are getting gas out of the gas line? You can (if you have one) put a manometer on the valve. Or you can open the gas line at the union and crack the supply valve for a moment (obviously not too long) and listen for the hiss and smell. Once had a heater out in the land fill area of the bay, with a galvanized gas line. The salt water corroded the gas line, it filled up with water, and cut off the gas supply :hammer:
 
View attachment 27562

I am experiencing very similar issues, I have a Teledyne Laars Lite 1 LLO pool/spa heater that is around 15 years old and started to act up. Initially it would take longer for the spa to heat up and it wouldn't always stay hot once it was up to temperature. Then it wouldn't heat up at all. I had a pool tech come out and check it and it seems like it would turn on, run fine for a few minutes and then switch off. The valve was making a clicking sound and the burners wouldn't stay on. The pool tech guy gave the valve a tap and it started to work again so he suspected that the valve was faulty and was sticking. It ran fine for a few weeks, same as before, it would take longer to heat up and wouldn't always stay hot, but at least it ran, and the valve continued to make clicking sounds intermittently. I decided to replace the existing "faulty" valve VR8305H 4013 with a new valve and bought one off the internet. They no longer make the Honeywell valve model I had but I got an identical one VR8345H4555 also made by Honeywell which was a universal replacement for the same part. The pool tech installed it and now it doesn't work at. The new valve continues to click and now the burners don't come on at all. I had hoped that my solution would be as simply as jjrepko's and I would just need to install the additional wire harness, but I don't think that will work as my valve has 3 wires (1 thick yellow wire, 1 thin yellow wire, 1 brown wire) and the wire harness only has 2 slots.

My pool tech now wants to replace the control board ($400), pressure switch ($81) and high-limits ($90) + $200 labor to see if that fixes the problem, but he doesn't make any guarantees that will work. I suspect they are trying to get me to just replace the whole unit with a new one they would install, but I think the one I have is salvageable since it partially worked with the old valve.

Any ideas what else I can try, or can anyone recommend a good pool guy in the Spring, TX (just north of Houston) that might be able to help?
 
but I don't think that will work as my valve has 3 wires (1 thick yellow wire, 1 thin yellow wire, 1 brown wire) and the wire harness only has 2 slots.

Could you clarify this a bit? You say the valve has three wires????I see three wires connected to the valve from the harness (heater wire system) and it looks like they are all hooked to terminals on the valve. I don't quite understand what you mean by the harness only has two slots...
 
Looking thru the schematic some more, I would have the tech check the transformer output voltage when the system is calling for heat. I suspect that you may have a failing transformer. (needs to check it with a load on it)
(edit)Also, do you have a picture of the terminals on the old valve we can see? I am suspecting that it may be wired wrong.
 
I'll take some more pictures this evening and post them.

As for the wire harness it is not installed in the pictures I posted. The wire harness would fit in where the two yellow and one brown wires connect on the valve, but the wire harness effectively joins the two yellow wires and only allows one connection for the yellow line. I suspect the pool tech has not wired it correctly based on looking at the old valve. I'll post some more pictures to show you what I mean.

Thanks for your help.
 
There comes a point when replacing a part or two on such an old unit isn't really worth it. If the "pool tech" didn't wire it correctly either A, it wouldn't work at all, or B the valve would always be open thus always be firing. Yes the valve you purchased does come with a wiring harness that is used in certain applications. It does tie two of the terminals together thus only two wires to hook up. Now if they knew how to read the schematic on the door of the unit, he should have wired it correctly. If he in fact did NOT wire it correctly, DO NOT HAVE HIM COME BACK TO WORK ON IT AGAIN. Find someone who does this type of work for a living and is hopefully licensed and insured. If this tech should do something wrong and cause a huge fire, look out. I know people always want to save a few $$$ but at what expense? Also keep in mind that you are investing money into an VERY old unit.

BTW, when you post a picture, make sure they are orientated correctly. My wife always yells at me when I stand on my head on the desk to look at these pictures.
 
If possible, can you get a picture of the lettering on the side of the black terminal on the side of the gas valve? I suspect that the brown wire is on a dead terminal. The two end terminals are the live terminals on that valve. Looking at the schematic, the two yellow wires are labeled as ground wires in the system and are shown as connected together. The brown wire is the hot power wire from the control board. One of the yellow wires shows as a return wire to the secondary side of the transformer. The other yellow wire comes from the temperature control circuit and returns to the same point on the transformer. I am thinking that on the original valve the two terminals on the valve may have been connected together. I think on this valve, the power has to go to one of the outside terminals ant the yellow wires need to connect to the other end terminal. Nothing goes on the middle one. If I was there with a volt/ohm meter (hint hint, plane ticket) I could figure it out in about 10 min.

Edit:
Paul posted before I got thru writing this. He makes some good points. especially the one about the tech. He does not seem like a very well trained tech if all he wants to do is change out parts that can easily be tested in about 10 min.
 

Enjoying this content?

Support TFP with a donation.

Give Support
Thread Status
Hello , This thread has been inactive for over 60 days. New postings here are unlikely to be seen or responded to by other members. For better visibility, consider Starting A New Thread.