Modine Hot Dawg Issue Solved

[caper177]

I tried to find an earlier post, I know many have had and are probably still having the issue of their heater blowing cold air due to the upper flame rollout switch tripping.

I had the repair tech over on 2 occasions but the problem still not fixed. I decided to take another look myself before I called again. With the side cover off you could see the upper flame rolling up and just about hitting the flame roll out switch. The upper part of the unit was covered with heavy carbon deposit.

I removed the front cover and took off the upper flame tube, you can remove them individually. The problem is the flame rolls out of the upper part of the tube. I used a pair of Visegrips and worked my way back and forth to pinch off the opening on the top side ONLY.

Before

After

I cleaned the carbon off the inside of the unit and re-installed.

The unit was fired up and lo and behold the flame is directed into the heating tube only, no more flame rolling out on top and overheating the flame roll out switch. I have some pics I will try to post.

Before

After

 

[mitymouse]

Wow...good find!

 

[HoosierBuddy]

That's super great and everything, but if the problem is the unit is experiencing carbon buildup...won't it just come back after a few days/weeks/months of operation?

Hate to be a Debbie Downer...but I wouldn't celebrate just yet.

[strike]Debbie[/strike]

Phil

 

[caper177]

Phil I think that flame you see rolling out in the 2nd picture was causing enough heat to trip the upper limit switch. I took a before and after video I sure wish I could post them.

 

[MetalMangler]

Hoosier - I'm willing to be proven wrong, but I think the carbon buildup is the result, not the cause. When I was training as a fire fighter they called smoke "un-burned carbon particulate". If the problem was that the flame was burning in the wrong location (and not burning fully) then you'd have your carbon buildup there. Directing the flame (fuel) down the tube where you have a full flame to get everything up to temperature and achieve complete combustion, you're probably looking at a successful fix.

That's my story, and I'm sticking to it.

MM

 

[HoosierBuddy]

Hoosier - I'm willing to be proven wrong, but I think the carbon buildup is the result, not the cause. When I was training as a fire fighter they called smoke "un-burned carbon particulate". If the problem was that the flame was burning in the wrong location (and not burning fully) then you'd have your carbon buildup there. Directing the flame (fuel) down the tube where you have a full flame to get everything up to temperature and achieve complete combustion, you're probably looking at a successful fix.

That's my story, and I'm sticking to it.

MM

Maybe I'm misunderstanding, but I take the OP to be saying that the only thing he did to fix the flame position problem was to clean out carbon buildup. Well...what caused the carbon buildup in the first place? Whatever that issue is (like maybe the unit isn't getting enough combustion air...or it's being overfired...or whatever) hasn't been fixed.

In my training at the gas company we learn that gas/air adjustment on appliances is critical and if it's off, carbon sooting is a likely result.

Phil

 

[ForceFed70]

Maybe I'm misunderstanding, but I take the OP to be saying that the only thing he did to fix the flame position problem was to clean out carbon buildup. Well...what caused the carbon buildup in the first place? Whatever that issue is (like maybe the unit isn't getting enough combustion air...or it's being overfired...or whatever) hasn't been fixed.

In my training at the gas company we learn that gas/air adjustment on appliances is critical and if it's off, carbon sooting is a likely result.

Phil

Better go back and re-read. He cleaned up the carbon while he was in there.

Look carefully at the before and after pictures he posted of the upper flame tube. THAT is what will fix the problem.

 

[caper177]

The soot was only a result of the flame being allowed to creep up the slot in the tube of which I merely pinched it off with a pair of Vise grips. Now the entire flame is directed straight into the heat chamber. I posted the pics containing the soot just to show how close the flame was coming out to the upper limit switch.

 

[Gregory M]

could you tack weld the burner where you bent it with the vice grips so it wont come apart later? just a thought.

 

[nehog]

Q: why only close up the upper gap, and not both? I'd have done both, but did I miss something?

 

[fatboy99]

The lower gap needs to be open for the burner to light. Looks like a center burner got installed in the top. The gap's allow the flame to spread out to light the other burners as the ignite r is mounted on the center burner.Or it is on my heater the OP'S may be in a different position.

 

[caper177]

could you tack weld the burner where you bent it with the vice grips so it wont come apart later? just a thought.

Funny you say that, I looked at the welder and was going to do just that but the metal is fairly thick so it should stay crimped together. After I assembled it and fired it up I realized I should have did the same thing to the lower part of the bottom tube as well but that one is far enough from the flame rollout switch to not cause nuisance trips.

 

[myveryfastgt]

I have the same problem with my 100 btu hot dawg. I had it installed and it keeps popping that flame roll out switch after running for like 20 mins constant.

No one can figure it out. This post is old but my heater is brand new and anyway i can see these pictures again? I think they have been removed because of the time period.

 

[James-W]

I have a Hot Dawg 60,000 BTU modine type heater and I have not had any issues with it. I am wondering if maybe the problem has been corrected on the newer models?

 

[myveryfastgt]

Mines from fall 2015.. Not really old.. Very disappointing when you pay someone 2500 to install and than they don't call you back after several weeks.

I am hoping i can figure it out with all your help!.

 

[James-W]

Mines from fall 2015.. Not really old.. Very disappointing when you pay someone 2500 to install and than they don't call you back after several weeks.

I am hoping I can figure it out.

I take it you are having the same issue?

Sounds like the company who installed your heater is not very customer service oriented. If I were you I would want to talk to the owner of the company in person. It may not do any good but at least I would know where I stand with that company and could then figure out the best way to go from there.

 

[myveryfastgt]

he is the owner... The only thing that makes sense is what a few said in this post to crimp the tube so the flame goes down only. Just wish the pictures where still up on this thread.

 

[James-W]

he is the owner... The only thing that makes sense is what a few said in this post to crimp the tube so the flame goes down only. Just wish the pictures where still up on this thread.

If the guy who installed the heater is the owner, then you are out of luck, it is obvious the guy isn't interested in correcting the problem.

You could maybe try contacting the manufacturer and inquiring about the problem. It is possible they have a fix for this and will help you to get the issue resolved. Most companies are pretty decent when it comes to solving problems for customers. They want you to be a satisfied customer who would recommend their product to others, not someone who is going to bash their product and discourage others from buying it. So they try to help as much as they can to get the problem fixed. For all we know they have a fix all figured out for this issue and they will send you a free kit.

 

[myveryfastgt]

Modine doesn't want to help me at all. They want me to pay someone to come out and look at it. I already paid someone 2500.00 and the money well drained out on this project. I am hoping its just the simple clamping on the tube would fix the flame from rolling back. Just hope i can get those pictures on the top of this thread. Just ***** when you hire someone and than they do this to you. And when the manufacturer doesn't offer any free help and wants to you hire someone. I will never buy another modine thats for sure but im stuck with it now.