LG Heater - Help with Lack of Heat!...

I've been using an LG heater for 25 yrs, but never had this prob so I'm looking for help or ideas.........

The problem is, I'm only getting 180 deg. max reading on the temp gauge on the TM. In the past I've always gotten 210-230 after cleaning the burner jets.

And I've always been able to regain lost heat by cleaning the burner jets and keeping it descaled, but that doesn't seem to help on this heater I have now.

The inside of the core looks clean, with no heavy scale deposits and I just cleaned all the burner jets the proper way with no noticeable increase in heat. I know it's getting plunty of gas......I recently replaced the regulator on my tank and I get a nice blue flame from the burner indicating the proper air/fuel mixture.

So what else could it be? Is there something else I need to check??

Have you changed your wand or jets on your wand. I talked to Les Judson he explained to me that the thermostat really has nothing to do with the heat getting any hotter if you turn it up to high you may get a little hotter water but only a spike of hot water. I was running 15 flow on my wand he told me go back down to a 4 or 6 flow and call me back.
I went back to 6 and the water stayed at 180 constant. Hotter with 4 but jets clog way to easy.
So in other word the heater # determines what its constant heat output will be. So if you up your jet size and set your thermo to high you will get hotter but only spikes of hot then it starts to drop off when you are in wide open areas faster with bigger jets.

Look at the inside of the heater seams like I remember there being a baffle inside the top that slowed heat exhaust. But I maybe wrong. And the jet sizing could cause it to.

My jet size has remained the same for thre last 2 yrs (6 flow)............and 2 yrs ago I didn't have a prob with 210+ deg.

The baffle is s5till there and is fine.

Do you have a lie detector or wand thermo maybe your temp is same but gauge is off???

or maybe a bad thermo couple sending unit

Check this out Dave
http://m.youtube.com/watch?v=qE6S5k5TK7Q

Did this just start or did you notice after your tm redo. Did you not run exhaust out of van lowering inside temps in your van?
I know its crazy but maybe that had something to do with it?

Will the temp come up if the wand isn't being used. If so you are moving water somewhere in the system or a line isn't connected right.

SCCC wrote:Do you have a lie detector or wand thermo maybe your temp is same but gauge is off???

No, all temps read are from TM temp gauge

SCCC wrote:Did this just start or did you notice after your tm redo. Did you not run exhaust out of van lowering inside temps in your van?
I know its crazy but maybe that had something to do with it?

I had good heat after the eng swap/upgrade. Prob started well after that.

Bummer I have no clue

I would check thermocouple and make sure its aiming in the right spot.. or control box isnt working properly. There isnt much else to the system so it has to be one of those two.

Have you just connected a tool to get water moving and watched the LG? how long does it burn before it kicks off?

You said you have a blue flame but is it the right height (pressure regulator ) that's the only thing left. If everything is working. The thermal coupler controls burner most times on my hot water heater which has the same control just no pilot striker eather works or not. But I have had press. reg. go bad. Worth checking.

I'll have to check thermocouple again.....But how do you test or know if there's a prob with the Unitrol controler??

What height should the flame be, Eddie?

On my hot water heater flame height is two or three inches.

Dave is your flame as big as it was, I just went and bought a reg but I made sure to buy one I believe rated for 80,000 btu's but I might have got a 120,000 btu.
I don't remember my heater just sits in my shop I don't use it, if I go by shop I will check what size it is.
I know I bought it at tractor supply warehouse.
Also the flame is pretty dang big in there and makes a good rumble when its going.
Your regulator maybe bad or to small.
I mean there is not much to these dang things at all.
You can get a new thermo at a ace hardware store.

The Saga continues, 150-180 deg on gauge at TM. What the Hell could be the F'in problem here?!?

So yesterday I noticed the heat being even lower it seemed, and since it's been a couple months since I last cleaned the burner jets I figured it was time again. So I did that last night, and running today no noticeable heat gain, maybe even worse, but certainly NOT any better.

WTH could be the problem here? I know of no way to test the flow/function of the thermostat, and sure don't want to pay $200 for a new one to find out it's not the problem. So far, I know there isn't a bunch of scale in the coil, the burner jets are clear again, and the regulator on the tank was replace awhile back. Looking at the flames coming off the jets, I think they actually look good, and are a nice blue color..

WWYD?...What would you do, any suggestions?

Is there a lot of soot build up on the coil where the flame heats.
Does the burner come on or cut off sooner than normal.
If you have a IR temp gun check the temp of the outlet line.
I know you said there is no scale but have you removed all the fittings and looked inside for build up. I haven't worked on those burners a lot but I worked on one that had build up so bad inside the coil that the heat could not transfer to the water properly. Worth a look if you haven't already

ACE Services wrote:Is there a lot of soot build up on the coil where the flame heats.
Does the burner come on or cut off sooner than normal.
If you have a IR temp gun check the temp of the outlet line.
I know you said there is no scale but have you removed all the fittings and looked inside for build up. I haven't worked on those burners a lot but I worked on one that had build up so bad inside the coil that the heat could not transfer to the water properly.  Worth a look if you haven't already

OK, I'll take them in order.....

I'm really not sure about soot build up on lower coil, but I can see threw the top and it's not bad.

Again, not sure about "normal on/off cut off" time of it.........what would be a "normal" amount of time?....Maybe one of you guys with a properly functioning LG could help me with this answer, by timing yours??.......it doesn't seem like it shuts off too soon, but again, I don't know what the normal timing should be?

I actually do have a IR temp gun, and will check it tomorrow........that's a good idea!!

"Scale build-up"
Yes, I have had all the plugs out of it to inspect for scale build up, and it looks fine.........very little to none in there.

Thank you for the post Eddie!.....do you have any knowledge on wither or not the thermostat could be a problem, or how I would go about checking it?

The thermostat
That's why I asked about the timing of the on/off of burner. I don't know the timing I didn't know if you had noticed any differenance. Cuting off to soon could be a faulty thermostat or some reason the heat is not being transferred to the water.
If the temp is right on the outlet line but the temp drops to fast. Then it could be thermostat kicking the burner on late or it could be worn jets on the wand dumping water faster than the burner can heat it.
If you are using a four jet wand with 1.5 gallon jets that's 6 gal but worn can go to 8 gal fast. Something else to try.

That's exactly what I'm running, 4 jet, 6 flow..........but Same no heat prob with 2 different wands, and the newest one with brand new jets in last two months. And this lack of heat prob going on since way before that.

Dave,   call Les at Judson.    He knows everything about the LG heaters,  hes been selling them for like 30 years.

He told me theres a way to safely modify a #3 to get almost same temps as the #4 can produce.  

Im going to be calling him as soon as we start setting up the Relia Built TM so we can do that to our #3.  

You have to open the thermostat and make an adjustment but youll want to talk to him first to make sure its done right and safely.      

He will likely also have an idea of why your not getting normal #3 temps

Great, thanks for suggestion.

I've been hesitant to call him because I'm not a customer of his, and never bought anything from him.

Les Jones is the coolest manufacturer I have meet in this industry. Give him a call. Here's one of his videos. That unutrol is 125.00