propane exhaust fumes in 145 RB baja edition

[ranchosinvacas]

I have a complex series of problems/questions that I would hope members can help me sort out. I towed our 2014 145RB on the freeway for 2 hours with the tiny Norcold fridge operating on propane. After arriving at our camp destination, I also fired up the 6 gal. propane water heater. The interior of the fridge was cold and the water got hot...but the interior of the TT had what I would say was an awful odor of what I'd call "propane exhaust". The interior gas safety alarm/sensor did not "sound" and a push button function test showed it to be seemingly working properly. Opening all windows and ceiling vents did a little to reduce the "odor". This smell was especially strong and prolonged inside of the under sink cabinet which is adjacent to the fridge, which is next to the water heater. After shutting off the propane tank on the TT tongue, I did an exterior inspection and found some slight soot discoloration on the sheet metal at the area that is next to where the fridge chimney exhaust exits when it is running on propane. A warranty issue at the time of purchase (2014) required that the fridge be removed from the cabinet so that a "tech" could service/repair the Norcold unit because it would not operate on propane, but only on 120VAC. Could the removal of the fridge have damaged a "spray in" foam cabinet seal that now, several years later, allows exhaust from fridge and/or water heater to enter the TT interior? Is it possible that the air flow caused by highway speeds forced or drew propane exhaust from the Norcold into the inside of the TT? After shutting off the propane, and allowing the odor to dissipate somewhat, the Norcold unit was switched over to 120VAC and continued to cool properly for the remainder of our 2 days at the campground. To be extra cautious, I only fired up the water heater once each day. We did not use the propane TT furnace over-nite because temps were mild each night and I had turned the thermostat to the off position. After the original/initial exhaust odor problem was vented after 3 or 4 hours, the problem did not return, but the fridge was by then on 120, and the propane two burner stove worked fine for cooking. Observations or ideas are most welcome.

[RogerR]

Both the water heater and the fridge vent to the outside and any smell of propane exhaust is very bad. Potentially, either one could leak and the CO monitor not be working. I would have a professional check them over before using again. If you inspect the seals and find an obvious bad spot I would repair it.

I tested my CO house unit by putting it in a sack that I put over my car exhaust pipe for a few seconds after first starting it. It went off in seconds.
Any LP exhaust smell in the RV could be a killer, be safe.

[ranchosinvacas]

This post serves as an up-date to my original post. I inspected the wall partitions, the cabinets, and the spaces containing the 4 on-boards propane operated units. Here's what I discovered...The water heater exhaust vent is located directly below the sidewall window on driver's side...so, if the window is closed but not tightly latched, then of course exhaust comes into the TT by convection when ceiling vents are open. If the Norcold refrigerator unit is operating on propane, then exhaust from its outside venting area seeps in through unsealed 1/8 inch gaps/separations between the full vertical length of the kitchen cabinet partitions between the sink and the backside of the fridge area underneath the single kitchen counter top...These unsealed gaps appear to be the result of a design flaw or the failure of installers to completely seal the cavity that houses the fridge. The 2 burner stove and furnace work as expected w/ no issues. I have yet to seal the gaps between the inside of the cabinet and the sidewall of the TT where exhaust from the fridge enters the TT. More work for another day!

[RichR]

One thing that affects exhaust odor is the burner is burning with a to rich air/gas mixture. Soot is also a product of a too rich mixture. You may have to adjust the mixture to allow more air into the mix.

[ranchosinvacas]

RichR;
Yes, Thanks. In addition to the still unsealed gaps running vertically between the fridge enclosure and the under sink cabinet storage area, I noted some soot build up on the fridge exhaust chimney's removable sheetmetal "cap/lid", along with some soot discoloration on the exterior of the upper plastic "grate/grill" and a small dull soot mark on the exterior sheet metal next to the plastic exterior grill nearest the exhaust chimney. I thought maybe an insect got into the chimney so I used compressed air to blow it out, also used a flexible length of mechanics wire to probe the length of the exhaust tube prior to use of compressed air. Some tiny amount of soot showed up after using the wire. I had previously covered the top of the chimney port in an effort to keep out insects prior to recent use and the odor/soot issue. I have not yet checked on flame color in order to judge a rich mixture. Also, all parts, fittings, fasteners, etc are in place and secure. So...How do I adjust the "gas/air mixture? Perhaps a u-tube video? Thanks for the response.

[ranchosinvacas]

So...I keep adding to my own postings.
I checked the propane exhaust chimney again and removed the baffle insert inside the exhaust tube.It was pretty soot discolored but not caked with soot. Also carefully removed the inspection port sheet metal cover and used compressed air to blow out the burner tube as best as I could without disassembling the entire igniter/thermocouple/burner unit. Did not open any of the propane connections so as not to risk tubing damage. Checked out the burner flame status on propane and found it to be good blue color rather than yellow. The fridge worked correctly on 120VAC and on gas. My best guess is that the unit was burning too rich and that the use of compressed air corrected the problem by blowing out dust, soot, and possibly insect debris. Still have to seal gaps in cabinet, wall, and fridge cavity.

[RichR]

I hope that fixed the problem.

[ranchosinvacas]

Another post Re; propane exhaust in 145RB Baja...Under counter gaps in the walls of cabinets next to the Norcold fridge enclosure have been sealed with a can of expanding spray foam. The results of the use of spray foam sealer are satisfactory as far as sealing the gaps,but the visual results are pretty unsightly under the sink cabinet. I thought of using caulk, but couldn't squeeze my arms and head under the cabinet in order to use the caulking gun. I did order screens to fit the exterior plastic grills in hopes of keeping insects out of the fridge area so as to lessen the chances of them causing a "burning rich" condition. Since I live in a very dusty rural area, I will continue to use compressed air as needed to try to keep dust out of the exterior of the fridge cavity/area.

[Charles in WV]

Look at my posts on thread BobK had about upgrades. I recently sealed my fridge and really helped its performance as well.
Soot in the chimney.and cleaning the burner on a Norcold N 300 series is considered maintenance to be performed. Watch this guy's YouTube videos and get an idea of how the fridges work. And don't work.

MyRVWorks.com

Attached are some of my pictures. My cabinet was still sealed but leaked a lot of hot air to the top. I put in extra bottom baffle and flashing in top corners as well as all the HVAC foil tape you see.
Charles