As a fulltimer I'm trying to assess my travel/boondocking capacity. I have a Dometic gas/elec frige. that is only marginally effective on gas. Depending on the ambient outside temp, my freezer ice will melt within a day or several; and the frige contents will be up to 50+degrees in the same timeframe. I realize that the unit must be level to operate on gas, so I can understand why the gas operation would be minimal while traveling... but I need to determine a benchmark. Does anyone have good results operating this (or similar) frige's working on gas?
Thanks,
dg
ps. What kind of battery life do you get on the electrical operation of the same frige? I'm not getting much time on my new 8 battery 6volt Interstates on a Trace 2500 inverter. Only a couple of hours, but that's another topic and I need to document some capacity testing!!!
DG,
The thing works the same on DC/AC as it does on gas. Heat applied to the "boiler". The gas is , in my experience, much hotter and works so very much better in terms of how cold it gets how fast. That dc mode is only for traveling with the generator running and nothing more. The AC mode is for parked in a park with shore power and again, it cannot be supported with the batteries. At least not realistically. The inverter will only power this while you have lots of current from the alternator.
You have a problem with your unit. The only problem you can't deal with is a punctured evaporator so you are in luck there. Call Dometic to get their take. A factory authorized shop should diagnose the problem for one hours labor charge and then you can order from Dometic and make the repair. Might save a hundred or so. The bright side is you have the best and most reliable refer on the market and it is well supported. Repair it Bro.
HTH
John
QuoteThe AC mode is for parked in a park with shore power and again, it cannot be supported with the batteries. At least not realistically. The inverter will only power this while you have lots of current from the alternator.
John, thanks for the prompt reply. I don't understand why the frige would not operate as any other user of 110 current. Why would say a microwave operate without
Quotelots of current from the alternator.
?
Please 'splain! Thanks...
Doyle,
Your reefer requires a heat source to operate. This heat source is either an LP flame or an electric element. Sounds like your LP flame is not hot enough. Burner may just need cleaned. When trying to operate off the inverter, remember that any electric heating element consumes a lot of electricity. As was mentioned, electric is for when you have a AC (or DC) power source such as shoreline, generator, or alternator producing power. Your microwave uses power for maybe a minute or two, your reefer uses power anytime the interior temperature is above the reefer thermostat setting. Hope this helps, Jack
Ahhh! So the wattage required to heat the electric "burner" is resistive and draws more current than the microwave.... gottcha! It's a matter of load usage. Thanks...
Hi Doyle,
Jack is correct about checking the burner tube for a build up of dirt. It's a very common of a problem with RV reefers.
You need good heat transfur from the burner, to the amonia for it to work properly. It's also possible that your burner
orfice is partally clogged and putting out a very low flame.
Good Luck
Nick-
Not to belabor this too much longer, butt shouldn't the frige maintain it operation (on ac) with the inverter on while driving with the alternator supplying extra charge?
Quote from: TexasBorderDude on December 05, 2007, 11:16:37 AM
Not to belabor this too much longer, butt shouldn't the frige maintain it operation (on ac) with the inverter on while driving with the alternator supplying extra charge?
Depends on how big your inverter is and how much power the reefer uses. It is when you are boondocking without the engine running that running off the inverter will suck down the house batteries. Jack
Quote from: TexasBorderDude on December 05, 2007, 11:16:37 AM
Not to belabor this too much longer, butt shouldn't the frige maintain it operation (on ac) with the inverter on while driving with the alternator supplying extra charge?
My experiences are with a friend's S&S... the gas option works MUCH better than the electric. I
believe I read that the AC element is 250 watts. I can't guarantee this, but I seem to remember reading it on the friend's Dometic. It's a lot to draw from batteries, but it should work from the alternator / inverter. Your initial question was about working on gas... it should work much better (colder) on gas than elec.
My personal experience on several vehicles is that the gas works significantly better than the electric. Even in ambient temperatures of 100 degrees plus. The amount of gas uses is so small that I never switched from gas to electric even when in a location for a few days that had shore power.
Ir is really a significant waste of power, due to inefficiencies, to operate an inverter from a 12 volt supply, let the inverter convert the 12 volts to 120 volts AC and then use that power to operate the fridge. Much better to operate it off the 12 volt directly if gas or 120 volt power is not available.
Richard
If it has never worked well either on gas or electric then it is likely to be badly installed. It is critical to get airflow up the back of the unit and if there is too much clearance between the unit and the wall, the air just flows up the wall instead of past the cooling fins. Baffles need to go from the wall to within 1/2" of the fins to force the airflow through the fins. Vents top and bottom need to be in the correct position and with no free space above the fridge at the back. Dometic have detailed instructions for installation.
Poor installation may also be the problem even if it appears to work OK on electric since if the electric element is a bit hotter than the gas flame, operation may appear OK but is really marginal and when it goes on to gas becomes sub-marginal.
Tony, you may be on to the prob. Do you have a link to the install notes? Works real well on elec., butt there's lots of clearance behind the unit. Thanks to all!
dg
Edit: I found http://www.dometicusa.com/pdf/825122801%20MO-FO%200438%5B1%5D.pdf which prescribes 1 inch MINIMUM rear clearance. The electric heat element seems to be inside the exhaust flue of the gas burner. On electric power it is warm to the touch. I plan to put the frige on gas tomorrow, and compare the heat in this flue. (I already know that on gas, the frost on the fins in the refrigerator compartment begin to melt within an hour... so I suspect there is less cooling on gas).... will prolly have to go to CampingWorld for a diagnosis. dg
As mentioned, if it works well on electricity, your problem is most likely minor. This is an absorption frig and runs on heat. Since the gas flame puts out more heat than the electric heating element, it runs best on gas. Therefore, it is clear that your gas flame is too weak. The "burner" which is barely more than a large pilot flame, could be clogged. I have heard that there is even a particular species of spider that likes the smell of propane and sometimes moves into the orifice. Check/clean the orifice, make sure that the gas supply is fully on and unobstructed. This is hopefully the simplest problem you will ever have to deal with. If it is a 3-way frig, then it can run on 12v when gas and 120v are not available. However, that function is just for supplying minimal cooling while running down the road; it does not work nearly as well as 120v or gas. You could run it on 120v through your inverter while traveling if it is within the capacity of your alternator to handle along with whatever else you want it doing. But there is no real reason to run it off your batteries through the inverter while parked; that's what the gas is for if your are without shore power, and it works great.
Quote from: Lin on December 05, 2007, 02:48:42 PM
As mentioned, if it works well on electricity, your problem is most likely minor. This is an absorption frig and runs on heat. Since the gas flame puts out more heat than the electric heating element, it runs best on gas. Therefore, it is clear that your gas flame is too weak. The "burner" which is barely more than a large pilot flame, could be clogged. I have heard that there is even a particular species of spider that likes the smell of propane and sometimes moves into the orifice. Check/clean the orifice, make sure that the gas supply is fully on and unobstructed. This is hopefully the simplest problem you will ever have to deal with. If it is a 3-way frig, then it can run on 12v when gas and 120v are not available. However, that function is just for supplying minimal cooling while running down the road; it does not work nearly as well as 120v or gas. You could run it on 120v through your inverter while traveling if it is within the capacity of your alternator to handle along with whatever else you want it doing. But there is no real reason to run it off your batteries through the inverter while parked; that's what the gas is for if your are without shore power, and it works great.
Great point Lin. I remember having to use an air hose and clean out the gas igniter/jet assembly every year.
Richard
Meeesoooo (me so) confused! It's dark now in Florida, so for drill I unplugged the frige and watched as the gas kicked in. A real virgorous flame appeared (about twice the size of my toothbrush!) butt it ain't enough to cool the unit. What's next? Check the electronic board?
ps. used the ubiquitous air hose earlier!
Is the unit fairly old or has it been sitting for a few years?
have heard that in cases like yours where the flame is correct and it still does not cool that it needs to be removed and turned upside down for a few hours. I do not recall what this does, but something about the ammonia. Others may know more.
Richard
Quote from: DrivingMissLazy on December 05, 2007, 03:22:54 PM
Is the unit fairly old or has it been sitting for a few years?
have heard that in cases like yours where the flame is correct and it still does not cool that it needs to be removed and turned upside down for a few hours. I do not recall what this does, but something about the ammonia. Others may know more.
Richard
I think it's about seven or eight years old. I've been using it daily since June. Do I remove the burner unit, the refigerator or turn the whole bus upside down?
dg
The turning is upside down fix is for when it just doesn't work. It is an attempt to clear a blockage. If it working well on 120v, it is not blocked. Are you saying that the flame is twice the size of a toothbrush meaning maybe 10 inches long! If so, that is huge. It should be a couple of inches at most. If you mean twice the size of the brush part only, that would be about right. The question than would be, does the flame stay that way or cut back after a bit. Also see if the flame is that way when it is plugged in.
Quote from: Lin on December 05, 2007, 06:11:42 PM
Are you saying that the flame is twice the size of a toothbrush meaning maybe 10 inches long! If so, that is huge. It should be a couple of inches at most. If you mean twice the size of the brush part only, that would be about right. The question than would be, does the flame stay that way or cut back after a bit. Also see if the flame is that way when it is plugged in.
Misspoke when is said toothbrush.... should have said twice the size of my toothbrush bristles... it seems to stay that way when it's on gas. There is no flame when it is plugged in... there is a resistance heater above the point where the flame would be.
Do not blow out the orifice out with an air compressor. The orifice is lined with a plastic sleeve that can be blown out and make a much larger hole. I have seen R-Vs burn because of this.I know you will here people say they do this all the time but beleve me it can happen.
Is the flame a nice 'hot' blue flame? If yellow tips, the draft may not be properly set..or the LP regulator isn't set correctly. Got a manometer?
The burner could be misaligned and not centered in the heat exchanger. They are a little fragile.
The burner flame should look like an all blue rosebud....usually between 1/2" and 3/4" high. No yellow tips.
My thoughts would be to have someone that can check the regulator and burner for correct adjustment, service the unit. And hope that you get a bonafide technician. These days so many 'technicians' don't seem to know Bo!
My Dometic works far better on LP than on 120Vac. It pretty much stays on gas whenever we use the coach.
One good thing, if the fridge cools on 120Vac, don't bother with pulling the unit out and flipping over. Ammonia "sludge" is not your problem. The absorption components are working normally.
I would also guess that venting isn't an issue for the same reason...it cools on 120.
You've probably got a burner or gas problem. That's my SWAG. ;)
Another thing...RV fridge burners can start fires. Be careful working on the burner.
Once repairs are made to the LP components, they should be checked for leaks.
Good luck, JR
Sorry about my excessive posts, but you say the gas function kicks on only when the 120 is disconnected? That's usually how the unit functions when the panel controls are set to "Auto".
You should be able to force "Gas" or "Electric" by selecting the appropriate buttons.
Do you have the owners manual?
NO problem. Looking at the control panel you should see a "gas" button, "Auto" button, and "Elect" button. Pushing the "Gas" button will switch the unit to gas without unplugging the 120 supply. And, pushing the "Elect" button will force only AC (or 12Vdc if you have a 3 way). Most newer units are 2 way. 120 or LP.
Pushing "Auto" button will select 120 as primary, and LP only if the 120 is interrupted.
That's how mine works. If you don't have these sort of controls....I got no idea. ???
JR
BTW, the board likely isn't bad either. The unit wouldn't light, or cool, if the board was bad.
Contact Dometic and see if the RM 7030 has had any recalls for the problem you have.
It seems to me you have a 'venting' installation issue. When it's on gas considerably more heat is generated by the flame compared to either electric heating element. This heat needs to be 'let out' at the top of the unit, this flow is in addition to the convection induced air flow over the coils. If your roof vent is not positioned properly to allow both hot air flows you could have the symptoms you describe. As others have said your situation is very unusual, these refers normally work much better on gas than electric power.
These type of issues is why I have an conventional household electric refrigerator.
Regards
Jerry 4107 1120
DG,
D U D E !!! You got your nickel's worth on this one, didn't ya? This place never stops amazing me and I hope you also.
One bit of confusion is the non-gas power. There are THREE way units that can go with 12 volts DC OR 120 volts AC OR gas. The newer ones work on AC or gas and will switch automatically or manually select either. You probably have the two way.
Your Dometic is the only refer that is considered likely to respond to the "remove and invert" fix. Even at that it isn't usually needed even if it get "clogged up". The manual I have read says to simply find a rough road to drive on and that will almost always return it to operation.
My guess at this point is that you have a dirty/clogged flu. At least partially. The elect element is right above the gas burner so it is a little confusing to me that you have this problem. At this point a tech might be in order as all the tried and true fixes aren't working. A one hour labor charge will get you the answer to "whats wrong" and if they won't agree to that go elsewhere.
I only had one Dometic and it has worked since 1990 when I bought the coach and it was 17 years old then. A Dometic is like luggage in that the only thing that is around longer is Herpies. That old girl has been off for 3 years at a whack in some cases and it is cold in 5 minutes after lighting the gas.
That gas flame was appropriately described as a "rosebud". It should also be as big as he said 1/2 to 3/4 inches of light blue flame and no orange. Still, it does carbon up and needs cleaned about every other month. I blew mine off with compressed air. Still, I am not contradicting the Nut that said you could damage a part. Mine is a model made in 73, remember.
Clean the flu and blow the thing out is my guess. After you blow it out check the flame to make sure you didn't clog one of the orifices with junk/carbon. ALL BLUE FLAME!
Good luck and let us know how it worked out.
John
Sounds exactly like there is not enough cool air coming in at the bottom and enough exhaust area at the top of the unit.
LP fridges need a vented air inlet at or near the bottom of the cooling unit. They also need a large vertical stack type opening above them to vent heat and fumes.
If you don't have good airflow, It will marginally only work on a.c. because as said previously the electric heater only has to dissipate 250 to 300 watts plus the heat extracted by the ammonia absorbtion cycle. ( On gas ) most burn 1 pound of LP a day.
That's a lot of residual heat to get rid of along with the absorbtion cycle heat.
I would say, Get your vents sorted out and fixed. You may need to close up some of that large open space to let air flow correctly too. ( means taking the unit out. )
And while out you can turn it upside down and lightly bang the boiler section with a rubber hammer to decrystalize the boiler...( Not hard !!! )..
Remember: The unit contains anhydrous ammonia, water and hydrogen. (don't let it out!)
Dave...
dg, that 1" minimum is the clearance required to any combustible panel behind the fridge and judging by the stories of RV graveyards with lots of badly-scorched fridge areas, it might be a good idea to line the area with metal sheeting anyway
There is another tech sheet somewhere that describes the problems when there is a deep space -- say 2" or more -- between the cooling fins and the rear wall, or a big empty space above the fridge. Both stop a good strong convective flow up through the cooling fins. I'll see if I can find it on-line for you. Possibly published for Australian conditions where these standard fridges just won't cope with temperatures over about 30ºC and they now have T(ropical)-rated units.
For what it's worth on my S&S when the gas kicks in if I am stading next to it I hear a 'roar'. I mean I can really tell that the gas is a burning! If you are not hearing that 'Roaring" noise I would say a simple adjustment at the air intake tube might fix you up! (Now if you get flames out the top of the bus...you may want to turn it back down a smidgin! ;D)
Jack
Yep! I've gotten my full membership fee's worth outta this one. Just what you'd expect from the folks that do the bussin' thing. Gotta good flame going, and so far this morning the frost on the fins inside the fridge hasn't defrosted. If it's still acting up, I've found a factory authorized repair here in Tampa that's close to the Interstate battery place. Will get two stones with one bird as I have the batts load tested. (My $20 HF load tester said they were ok, butt...my 920 amp/hour bank dropped from 13.14v to 12.31v (30% discharged) in just 2 1/2 hours of sat. receiver and tv and a 5 minute load on the microwave. Didn't mean to hijack my own thread! Will keep 'ya posted.
dg
Texasborderdude: Read the the other replies again. Your refrigerator uses a boiler to boil the refrigerant. More heat equals more boiling and more cooling. Nothing to do with control boards, voltages or batteries. When it is working properly, the gas flame produces more heat than the electric element. Your problem is simply not enough heat (do you have a blue flame?), or it is not large enough, or it is not in the right place.
Come back when you have the problem of the refrigerator being too cold on gas. Most dealers don't know the answer for that one!
Quote from: Stan on December 06, 2007, 07:18:32 AM
Texasborderdude: Read the the other replies again. Your refrigerator uses a boiler to boil the refrigerant. More heat equals more boiling and more cooling. Nothing to do with control boards, voltages or batteries. When it is working properly, the gas flame produces more heat than the electric element. Your problem is simply not enough heat (do you have a blue flame?), or it is not large enough, or it is not in the right place.
Stan: Thanks for the input.
Got it! Please read me again; the battery situation is separate, I understand... just want to save a trip. The flame is blue, heats the exhaust flue about the same to the touch as the elec element. I'll see if I can get a picture of the flame. Just how do I relocate the place for the flame?... as it seems that's all that's left. ;D Thanks to all, I do remember that I'm the one asking for help!
ps. The coils were cool to the touch on gas; switched back to elec and they're heating up! I agreee "it's simple"... butt nothing simple is ever easy!!!!
pps. Was able to post a picture of the flame.
Your FLUE baffles are missing.... They hold the heat in the tube when using gas mode so that the heat has time to absorb into the boiler.
Should either be a restricting chimney baffle at the top of the burner tube or a flat zig-zag strip that hangs down in the chimney tube with a metal rod attached.
The other way is a cover (shroud) over the burner section that restricts air flow up into the burner tube. ( The burner gets it's air from outside the shroud )
I had the same problem with an RM2801 until I slowed the air flow down.
It would work with the shroud on but not work well with it off.
Just a thought.....
Quote from: DrDave-Reloaded on December 06, 2007, 09:10:10 AM
Your FLUE baffles are missing.... They hold the heat in the tube when using gas mode so that the heat has time to absorb into the boiler.
Should either be a restricting chimney baffle at the top of the burner tube or a flat zig-zag strip that hangs down in the chimney tube with a metal rod attached.
The other way is a cover (shroud) over the burner section that restricts air flow up into the burner tube. ( The burner gets it's air from outside the shroud )
I had the same problem with an RM2801 until I slowed the air flow down.
It would work with the shroud on but not work well with it off.
Just a thought.....
Thanks Dr... I found http://gasrefrigeration.net/dom_techdata/7030_7732SM.PDF and it looks like the flue is the problem. Gotta wait til I unload the fridge and then pull it out from the inside. (Only an access panel on the outside, butt can't get the flue off the back) Then I can clean it and check for the flue baffle.
Appreciate all the help!
Doyle - there used to be a good refer guy at RV Mobile Medic, who just happens to be next Interstate Batteries - coincidence ? - I think not - I have not used them in a long while as there is nothing RV in my bus - but call and see if they have anyone - # is 813-935-3268 - HTH
P.S. - I never heard from you?
Have not read the other posts, ssoooss again if I duplicate.....sorry. When we had our solar cabin/homestead we had to run a small dedicated 12 vdc muffin suction fan above the propane burner inside the exhaust stack during hot weather to get the reefer to make and hold ice cubes. Made a tremendous difference in efficiency and propane comsumption. We also found the beginnings of a substancial wasps nest in the vent pipe. :) :) :)
Texasborderdude: I just went back and read all your posts again. You say that you think the refrigerator is seven or eight years old. I presume that this means that you did not buy it new. Did it ever work correctly on gas after you bought it?
When someone posts a question about their refrigerator not working, it is assumed that all the pieces are there, that it is installed correctly and was working fine until now. If all of these facts are not true, then it is almost impossible to guess what might be wrong.
From what little I have seen and what less I know.....you are missing the entire bottom assembly of that refer. The burner should be contained within a sheet metal shroud that has a little door like hinged sliding thing. That "thing" restricts the flow of air going up the chimney. Before you go to the trouble of pulling the refer, get a pictorial diagram of the thing from the dometic manual and verify this. Missing parts from the mfr at the time of mfr????? Dometic might give you what you need. A refer guy probably has the item siting on an old carcass "out back". You will be able to install that with the refer installed. I removed mine once to do a thorough cleaning. Sheet metal screws held all together...... Even I can do "Phillips".
HTH
John
Quote from: Stan on December 06, 2007, 05:46:35 PM
Texasborderdude: I just went back and read all your posts again. You say that you think the refrigerator is seven or eight years old. I presume that this means that you did not buy it new. Did it ever work correctly on gas after you bought it?
Thanks Stan, yer right! I bought the coach from the fellow that converted it. He bought the unit new from Dometic and installed it. As far as I can tell it is complete, installed correctly and has always worked well on elec. (never on gas.... I've owned it since Feb. 07)
Quote from: Stan on December 06, 2007, 05:46:35 PM
When someone posts a question about their refrigerator not working, it is assumed that all the pieces are there, that it is installed correctly and was working fine until now. If all of these facts are not true, then it is almost impossible to guess what might be wrong.
I hope I've not violated any protocol with you for not having owned it from day 1.
Quote from: JohnEd on December 06, 2007, 11:14:43 PM
.....you are missing the entire bottom assembly of that refer. The burner should be contained within a sheet metal shroud that has a little door like hinged sliding thing. That "thing" restricts the flow of air going up the chimney.
John
John, good catch... I removed the cover to get a picture of the flame. With that in place, doesn't cool on gas. Thanx.
Texasborderdude: Nothing wrong with buying used equipment but it creates it own set of problems when it doesn't work. You probably don't know if the gas system ever worked for the original owner. If not, there may be a manufacturing defect that is impossible to correct. If it worked originally, someone may have serviced it and in the process made some change that is not obvious to you, and certainly not obvious to people who have not seen the unit.
As almost everyone has emphasized, RV refrigerators run on heat under the boiler. The gas burner puts out a lot more heat than the electric element. I have no idea why you are not getting this heat to the right place.
On the older model units with a pilot light, the main burner seldom came on in moderate ambient temperature. The pilot light provided enough heat to keep the freezer frozen.
Stan, thanks for your continued input. It's got me stumped too! It's almost gotten to be a personal challenge and I'm going to ice up my ice chest, unload the fridge and pull the thing out and check the flue. The service manual indicates tests of the upper and lower circuit boards if it cools on elec but not gas; but also sez the flue should be cleaned anually. With the fridge out, I'm going to see if I can rig the flue so I can access it without removing the unit. Thanks again, and I'll post the results.
dg
Hey texasborderdude,
Think you may be able to look down the flue and clean it thru the top vent cover.
The heat from the electric or gas in the flue must exit the top vent.
For mine it's amost a straight shot, but I pull the heat mixer insert and go down with an old speedometer cable I keep around.
Give it a try, lots easier than pulling the unit.
Frank
Doyle, being around that bus a few times i can assure you it worked on gas because Brown would have drove the supplier nuts till it did and never did I know of him buying anything used for that bus.But you do need to call Dometic they had problems with the eye level controls and the auto change over and had several recalls (on mine anyway)
I've seen a number of these Dometics that were marked 1500 BTU input. Just for drill, I divided the 1500 by the number of BTU per watt hour (1500 / 3.413), which equals 440 watts. On the unit that I checked, the heating element was 440 watts of AC. The DC element was only in the couple hundred watt range.
It seems to me that AC and gas ought to cool about equally, since the heat input is supposed to be the same. The paperwork says that the DC is only for holding, not for cooling the unit.
If someone was to run the refrigerator on AC from golf cart batteries, then the batteries would have to provide 500 watts to the inverter, or more. Since golf cart batteries only hold 1 1/3 KWH each, and since they shouldn't be discharged all the way, I would figure they would be good for about 2/3 KWH, in practice.
If the refrigerator was running about half the time to keep cold, that would mean that a pair of golf cart batteries would be good for about 5 hours of normal operation, if there were no other loads. To go a full 24 hours would take 5 pairs of golf cart batteries. That would add up to 650 pounds of batteries.
The same day should take only about a pound of propane, if it was run on gas. If I fouled up the calulations on this, someone please correct me!
Tom Caffrey
New gas pressure regulator doubled the gas pressure output. Will advise if this solved the problem. (Got some heat in the coils, but can't tell just yet on the cooling efficiency.)
dg
I'd suggest placing the malt beverages in an iced cooler. Better than waiting for the fridge to cool down.
Your Dometic will take an hour to feel cool on the walls, and overnight to get cold.
If you haven't had it turned completely off for a while, you may have forgotten just how long absorption fridges take to cool down to ice-cream maintaining temps.
Hope it works! JR
Quote from: TexasBorderDude on December 12, 2007, 03:23:42 PM
New gas pressure regulator doubled the gas pressure output. Will advise if this solved the problem. (Got some heat in the coils, but can't tell just yet on the cooling efficiency.)
dg
Hmmm.. That would do it. If it doesn't get the 11" WC gas pressure it wouldn't heat
enough properly. ( it would still burn blue flame just not enough of it.)
Makes me wonder if someone had replaced the regulator with one off a gas grill?,
They operate at about half of the regular units. 4" WC on the two I had recently.(low flow)
Makes sense....
Just a thought. I haven't read the string because it is too long but this happened to me.
When I bought my bus it had NO upper vent of any kind for the frige!! Hard to believe but I was so dumb (never owned any kind of RV) that I didn't know the difference.