What's the best/easiest way to check flue?

[JWatkins]

I have reported that I had issues with my refrigerator turning off and throwing a NoCo when on propane. It works well on electric. I took it to a "qualified" Norcold service center and they kept it overnight and assured me it was the cooling unit. Since electric and gas use the same cooling unit ($2200) , that was malarkey. Anyway, I was wondering, now that the weather is finally cooperating, what is the best/easiest way to check the flue for obstructions?
What else could be wrong? The burner is clean and it has a nice bright flame. The unit will run a long time on gas, then it will shut off. I am suspicious as to whether or not this is during the normal cycling or not. I ran it on gas all the way home from Quartsite without issue, but it shut off in my driveway after several hours. The unit was level.
Thanks, Joe

[heavyequipt]

Quote:

Originally Posted by JWatkins I have reported that I had issues with my refrigerator turning off and throwing a NoCo when on propane. It works well on electric. I took it to a "qualified" Norcold service center and they kept it overnight and assured me it was the cooling unit. Since electric and gas use the same cooling unit ($2200) , that was malarkey. Anyway, I was wondering, now that the weather is finally cooperating, what is the best/easiest way to check the flue for obstructions? What else could be wrong? The burner is clean and it has a nice bright flame. The unit will run a long time on gas, then it will shut off. I am suspicious as to whether or not this is during the normal cycling or not. I ran it on gas all the way home from Quartsite without issue, but it shut off in my driveway after several hours. The unit was level. Thanks, Joe

If you have a roof vent,take off the cap,the flue pipe should be at either end of the retangulor opening.It is approx.1 inch in diameter.There should be a metal plate at the top of the flue that supports the baffle.

[JWatkins]

Thanks. I checked the flue after having to cut into a screen that was under the rooftop cover. It had the baffle in place and I ran a swab completely through it an it was pretty clean. I checked all board connections and then started the fridge on gas. After about 2-4 hours the flame was out and the NoCo was showing again. I think it may be not able to restart after reaching temp and shutting off. That is probably the board?
Joe

[Gary RVRoamer]

Could be the board, or could be the igniter itself or the circuit to the igniter (corrosion on the wire end, etc). Since it seems to light initially, I would guess that the heat of the burner is causing something to open up. A hair line crack in the igniter (which is also the flame sensor) or a tiny defect in the circuit board would react like that. The igniter is a whole lot cheaper if you are going to start swapping parts.

Poor propane flow to the burner will also cause a NoCo fault.

[JWatkins]

Quote:

Originally Posted by RV Roamer [Gary] Could be the board, or could be the igniter itself or the circuit to the igniter (corrosion on the wire end, etc). Since it seems to light initially, I would guess that the heat of the burner is causing something to open up. A hair line crack in the igniter (which is also the flame sensor) or a tiny defect in the circuit board would react like that. The igniter is a whole lot cheaper if you are going to start swapping parts. Poor propane flow to the burner will also cause a NoCo fault.

I decided to call the owner of the shop that mis-diagnosed the issue and chat with him. He was more than a little perturbed and stated all the experience his guys have and the fact that he never gets calls like this.

I asked if he understood why I might be a little more than upset as I almost had them do the work to replace the cooling unit, but didn't have time before we had to be in Quartzite. That would have been about $3000 and it wouldn't have been the problem at all. He said bring it in since he wanted to investigate why his tech came to that conclusion in the first place. He has had the rig for a week and no call so far.
Joe

[a k]

It might be going off on high temp. Do you have exhaust fans on top? It seems to work OK when a breeze going down the road and then shuts off when sitting still. If the flue was obstructed you would get a yellow flame and black soot.Flue gets a lot hotter on propane than on electric.
Just an opinion

[Ray,IN]

You may download the installation instruction manual at: Aero-Rv.com - Aerolite Ultra Lite RV Travel Trailer and Expandable Hybrid Campers
if you wish to double check the installation. If you have a side-wall vent installation it is critical it be done correctly.

[wagonmaster2]

It still amazes me that so many shops have to keep a coach for a week to several weeks to get anything done on it. They usually don't charge you for 40 hours of labor each week, what do they do all that time? I had a dealer keep my coach for 3 weeks and only showed 4.5 hours labor. The only part they ordered was a rear tail light lens which shouldn't have taken over 3-4 days. I've never been back to that shop since and that was 4 1/2 years ago.

Wagonnmaster2

[Ray,IN]

Quote:

Originally Posted by wagonmaster2 It still amazes me that so many shops have to keep a coach for a week to several weeks to get anything done on it. They usually don't charge you for 40 hours of labor each week, what do they do all that time? I had a dealer keep my coach for 3 weeks and only showed 4.5 hours labor. The only part they ordered was a rear tail light lens which shouldn't have taken over 3-4 days. I've never been back to that shop since and that was 4 1/2 years ago. Wagonnmaster2

If anyone can answer Wagonmaster2's question with a plausable reply, I certainly want to read the response!

[JWatkins]

I got my coach back today. They stated that it was rust in the flue. I told them that I had run a swab through it and it came up clean. They said " yes, but you only went through the middle" ??? Anyway, they said the hit the flue with a piece of re-bar driven by a hammer and lots of stuff fell. I asked " Well, if it was rust, then why did it start well and then shut off after several hours and not start again unless I shut it off and did a re-start? No answer. In any case, it seems to bee working now. It was 23 degrees in the lower section with the fridge setting of 7?
Joe

[Gary RVRoamer]

Tough to argue with success, so maybe they were right? All you can do is keep a watch on it.

Guess the cooling unit was ok, though. Good thing you didn't spend that $3000!!!

[JWatkins]

Agreed!
Joe

[Roadking]

Joe: Glad to hear you got the problem fixed. Have you checked your cooling unit serial number against the Norcold recall list? The cooling unit serial number is located on the small accumulator tank that is above and to the left of the flue and burner stack. There's serveral posts on the forum in regards to this recall and I'e seen two rigs burn recently where the fire source most likely was the fridge.

My fridge was in the list and it took about 2 hours to get the recall taken care of. They replace the insulation around the stack and install an over temp sensor on the stack. Also, if the techs were pounding on the stack I would be concerned as any damage to the insulation could be a potential issue.