RV fridge How level is level?

[sweeney153]

So how level is level?

The manual for my fridge says "When the recreational vehicle is stationary it must be leveled to be comfortable to live in. If the refrigerator is properly installed, i.e. the freezer shelf parallel to the floor, the refrigerator will then also perform well. A bubble level should be placed on the freezer shelf. "

I'm much more comfortable with numbers. How many degrees out of level is OK? I'm comfortable with more of a tilt then my wife. I searched the archives and found a posting saying that tilt one way is OK the other way is bad.

Whats the real deal? The fridge in my coach is DOA. Has not worked since I had the bus. I have another RV fridge in my basement that I know works. I am trying to decide how much of a pain it would be to use. I have thought of buying a house fridge, but that's several hundred $$$$ that I don't have right now and would involve cabinet work which I suck at.

Thanks in advance for you help and opinions.

Kevin

Sweeney 153

[Tenor]

I wish I could give you numbers, but the bubble gauge has been the easiest way to go.  I don't have a leveling system other than blocks.  I just level to the point that the bus looks good and I know I'm not going to roll out of bed.  I have never had a problem with either RV fridge I have had, and I've only had 2 because as I did my second conversion, I found a newer one.  If the 2 you have are the same size, swap'em!

Glenn

[Jriddle]

I have wondered this also. I have heard all the stories of keeping the frig. level. I have to say with my old trailer and now my bus I run the frig all the time while traveling. I get bus as level as possible and have not once had a problem. If you have a spare change it out. I have heard of turning the one that's not working upside down for a while and then giving it a try. I had a friend that had to do that every year. If I had that much trouble I would get a new unit.

John

[Sean]

Level is critical in the plane of the condenser, and much less critical perpendicular to that plane.

In plainer English, if the fridge is installed "normally" meaning the door is parallel to the direction of travel of the bus, and the "back" of the fridge is up against the side wall of the bus, then leveling the bus front-to-back is more important than side-to-side.

Numbers are hard to come by, but I would suggest an absolute maximum of 3° front-to-back and preferably much less than that.  I would also say that as much as 6° side-to-side would not be a problem.  If you are more comfortable with percentages, 3° is about a 5% grade, and 6° is about a 10% grade.  If you have a 40' coach, that means the front of the coach can be no more than 2' higher or lower than the rear.  I don't know about you, but I would find that kind of gradient "uncomfortable" for daily living.

-Sean
http://OurOdyssey.BlogSpot.com

[kyle4501]

So how level is level?

. . .  I'm comfortable with more of a tilt then my wife. . . . . .

Make the wife happy & see if the fridge complains - if not, all is good! 

We have used ours in the TT at 1/2 bubble off & it worked OK.

Use what you have & see if it fits your style, - that's what I'm doing with the TT - experimenting with things to see if they work in practice as well as theory. 

[bobofthenorth]

Whats the real deal? The fridge in my coach is DOA. Has not worked since I had the bus. I have another RV fridge in my basement that I know works. I am trying to decide how much of a pain it would be to use.

I don't really know that much about RV fridges but I have used them a lot.  What Sean says matches our experience - they can tolerate a lot of out of level front to back but not as much side to side.  The way it was explained to me is that the coolant has to be able to travel by convection through the cooling coils on the back of the fridge.  If you are too much out of level then the convection current has to flow uphill or downhill - whichever direction it won't go. 

At one point we had a fridge that was "DOA" in a relatively new trailer.  I had an RV tech that worked for me who helped me resurrect the fridge.  He said to get the fridge absolutely level and turn it on and then bang on the coils.  We got a little bit of cold happening that way and then he told us to drive with the fridge turned on.  That fridge was always very sensitive to side to side levelling but we did get it back to a usable condition.

[JLL]

I'm not an expert on refers but I think they have to be nearer to level if they are on gas than electric.
Because the flame will doing damage.
JLL

[Lin]

The owner's manual should give you the parameters.  Mine says it should be withing 3 degrees side-to-side and 6 degrees back-to-front.  Actually the same as Sean's recommendations.  We have those arced bubble levels that, I believe, are calibrated to degrees.

[Sean]

I'm not an expert on refers but I think they have to be nearer to level if they are on gas than electric.
Because the flame will doing damage.

Not true at all.

The sensitivity of absorption refrigerators to out-of-level conditions has nothing to do with flame direction but rather with the flow of ammonia (gas and liquid) in the condenser, evaporator, and absorber.  Even slight off-level conditions can cause the fluid to pool, forming an obstruction.  Not only will the fridge stop cooling, it can be damaged.

How the working fluid is heated makes no difference to the process and the problems that occur with it.  These problems, as I said, happen at very low angles, just 2°-6°.  That's enough to stop cooling or break the unit, but not enough of an angle to cause burner issues.  IOTW, if your rig is tilted enough for the direction of the burner flame to be a problem, it's way past where the ammonia will stop flowing.  Don't forget, these burners are designed to work with the rig in motion, where angles can get much greater than 6°.  The ammonia does not have issues under way because the motion of the vehicle itself prevents pooling and the passages from becoming obstructed -- the level proscription only applies when parked.

For a good treatise on how absorption refrigerators work, look here:
http://home.howstuffworks.com/refrigerator5.htm

-Sean
http://OurOdyssey.BlogSpot.com

[pvcces]

I noticed that the degrees and the directions got crossed up a few times in the above posts.

Our Norcold manual says that we can have 6 degrees of tilt from it's front to back or 3 degrees from it's side to side. Ours is mounted the conventional way, with the with the coils parallel to the direction of travel.

This means that we can park next to a curb, where the crown of the road is most noticeable, and we don't have to worry about the slope unless it is fairly extreme. If the crown is enough to bother us, we just turn the unit completely off, and try remember to turn it back on when we are ready to leave. We DO consider the temperature and limit the time off if it is very hot.

Something more than 10 years ago, the refrigerators were more sensitive to lean. The most recent onces are much more tolerant.

We never have trouble with our Norcold, but the Dometic was terrible for giving trouble, but leaning was not the issue.

For what it's worth.

Tom Caffrey

[sweeney153]

If you have a 40' coach, that means the front of the coach can be no more than 2' higher or lower than the rear.

2 Feet front to rear it quite a tilt.

Your right

[Lin]

That's got to be wrong.  A 2' difference between front and rear is going to be a lot more than 3 degrees.  I just ran my 35 footer up on 7 inch ramps in the back.  That moved to level 4 or 5 degrees.

[Nick Badame Refrig/ACC]

Hi Sweeney,

I tell folks if you place an ice cube on your kitchen table and it slides onto your

floor, well then common sence should kick in about that time!!

Older reefers with amonia systems will gell up after time taking sometimes days

to cool down in the box. Flipping the unit and heating the condencer coil will almost

always work. If the condencer coils are badly rusted, then replacment might be the

way to go.

Good luck
Nick-

[Sean]

That's got to be wrong.  A 2' difference between front and rear is going to be a lot more than 3 degrees.  I just ran my 35 footer up on 7 inch ramps in the back.  That moved to level 4 or 5 degrees.

That's 2' (on a 40' coach) difference between the front bumper and the rear bumper, not at the wheels.

The wheelbase on a 40' coach could easily be just 24'.  5% of 24' is just 14.4", so you'd need only that amount of ramp at the wheels to make a 3° slope.

That said, if running your coach up on 7" ramps gave you a 4° slope, your wheelbase would be only 8'4".  Perhaps you are thinking of a grade of 4%, rather than an angle of 4°?

3° is more than most people imagine.  Think of it this way: to get a 45° slope, a 40' coach would have to have its front bumper 28' in the air with the rear bumper on the ground, and the ground shadow would also be 28' long (remember Pythagoras: the diagonal of a square has a length of the side times the square root of 2).  3° is 1/15 of 45°, and 1/15 of 28 is 1.8'.  Of course, the relationship between angle and rise is not linear, which is why it's not 1.8', but it should give you a sense of what number is "reasonable."

-Sean
http://OurOdyssey.BlogSpot.com

[gus]

As Sean says, side-side leveling of the frige is the most important and while it is moving there is no problem.

I don't think that frige back to back tilt is even a concern. A look at the coils will show that it would be very hard for this to be a problem, but the frige side tilt problem is pretty obvious when you look at the Z coils at the back.

The reason for this is the ammonia return coils are "Z" shaped and too much tilt levels the long Z leg so it can't drain back to the boiler.

I doubt that a day or two out of level will cause any problems so I don't worry about it. Often I have no choice about parking spots, but I wouldn't do it more than a couple of days.

As for the bubble indicator,  I read somewhere that it is safe as long as the bubble is touching the centering line but at least half a bubble is best. I go by this without worrying about it too much.