Refrigerator operation on propane at high elevation

[elongest]

(2014 E-21), I was/am having frig. issues. The stove burners seemed to work great and the flames did not decrease with all burners lit one buy one. I checked my LP pressure with a meter and it was only 7.9" WC instead of 11" WC with no flow or load. I was able to adjust the old regulator to 11"WC but ordered a MEGR-253 and plan to install today. Several others have replaced their regulator so don't rule out a fairly new regulator. Also with frig issues I would have the LP pressure checked with a meter.
Eddie

[rbryan4]

7 to 9 inches of WC pressure may not be a problem at high elevations. That's because there is less oxygen to mix with the propane. Some have found that reducing the regulator pressure to around 8" when camping at very high elevations actually works better.

It could be the regulator, but based on what the OP describes, it could also be an issue with fridge gas valve, burner, or electronics.

[alanmalk]

Originally Posted by elongest

...The stove burners seemed to work great and the flames did not decrease with all burners lit one buy one.

A slightly more rigorous stress test would be to turn on all the stove burners and then kick on the furnace. If the stove flames remain stable then the regulator is likely functional. Without looking at the specs, I suspect the furnace puts a much bigger load on the propane system than the 'fridge.

--
Alan

[elongest]

FWIW
I just installed a standard MEGR-253 regulator. With the range (3burners) (no oven), frig. furnace, and water heater running full bore I adjusted the pressure to 11" WC. In a static no flow state it read 12.5" WC with everything turned off. New out of the box it read about 13.5" WC static. I am on the water on the east coast very close to sea level.
Eddie

[Chuckster]

Good morning,
I changed out our regulator to the subject model and we noticed a low pitched squeal (almost like a sigh) that pulses when there is demand like the water heater or furnace. Any thoughts on the cause or a fix?
Otherwise, our fridge is performing well at 9,100 ft.

[Chuckster]

Originally Posted by Chuckster

Good morning,
I changed out our regulator to the subject model and we noticed a low pitched squeal (almost like a sigh) that pulses when there is demand like the water heater or furnace. Any thoughts on the cause or a fix?
Otherwise, our fridge is performing well at 9,100 ft.

Update, it stopped making noise shortly after posting this.

[hrewer]

Hi. We have a 2016 17B with a Dometic 3 way fridge #RM2354. While we were camped at Coldwater Campground in Mammoth, CA (8900') our fridge worked during the day but would blow out and try to restart repeatedly, in the early morning hours. As soon as the air temp warmed up, it would resume working. After checking the manual I learned that Dometic doesn't recommend this unit for over 5500'! That knocks out a lot of great places.

I contacted Dometic and here is their reply;

Thank you for contacting Dometic. I afraid this is a double edged sword type of answer....in short yes you can make this work in higher altitudes but there is a catch. In order for the unit to function in high altitudes you must locate a mobile LP tech that can come to the unit at the elevation you plan to camp at and change the regulator and set it to work where you are....once you are done camping there that regulator must be removed and the gas tank water column adjusted again with the original specs to operate safely. I also will tell you that if you do this and change the regulator you will void the 2 year warranty due to safety concern and liability. I am sorry I don't have better news for you on this. This is a problem with any LP product out there, it really has nothing to do at all with the refrigerator. This altitude thins the LP to a density too thin to maintain flame and cooling.

We are wondering if anyone has had success with a less awkward workaround. We are heading for the North Rim of the Grand
Canyon in a couple of days and will be at 8300'. We'd appreciate any inspiration on this topic!

Thanks Howard

[rbryan4]

Originally Posted by hrewer

Hi. We have a 2016 17B with a Dometic 3 way fridge #RM2354. While we were camped at Coldwater Campground in Mammoth, CA (8900') our fridge worked during the day but would blow out and try to restart repeatedly, in the early morning hours. As soon as the air temp warmed up, it would resume working. After checking the manual I learned that Dometic doesn't recommend this unit for over 5500'! That knocks out a lot of great places.

I contacted Dometic and here is their reply;

Thank you for contacting Dometic. I afraid this is a double edged sword type of answer....in short yes you can make this work in higher altitudes but there is a catch. In order for the unit to function in high altitudes you must locate a mobile LP tech that can come to the unit at the elevation you plan to camp at and change the regulator and set it to work where you are....once you are done camping there that regulator must be removed and the gas tank water column adjusted again with the original specs to operate safely. I also will tell you that if you do this and change the regulator you will void the 2 year warranty due to safety concern and liability. I am sorry I don't have better news for you on this. This is a problem with any LP product out there, it really has nothing to do at all with the refrigerator. This altitude thins the LP to a density too thin to maintain flame and cooling.

We are wondering if anyone has had success with a less awkward workaround. We are heading for the North Rim of the Grand
Canyon in a couple of days and will be at 8300'. We'd appreciate any inspiration on this topic!

Thanks Howard

I know what Dometic says. They have legal liabilities and they have to say that. But, for what it's worth, many folks have had success lowering the regulator pressure to 7-9 inches of WC pressure when camping at very high elevations. Then, once you return to lower elevations, just set it back to 11 wc inches. All you need to perform this monumental task is a cheap manometer and a screwdriver.

[hrewer]

Our regulator is a Marshall Excel MEGR 253. We now have a manometer so we could give it a try.

[Rossue]

This is all news to me; while it makes sense- we camp a LOT at high elevations and have never had a problem- well we did hear squealing and like others replaced the stock regulator with a Marshall Excelsior MEGR-253.

Edit: seeing that you have the same regulator you might need to service the burner/flue.

[rbryan4]

Originally Posted by Rossue

This is all news to me; while it makes sense- we camp a LOT at high elevations and have never had a problem- well we did hear squealing and like others replaced the stock regulator with a Marshall Excelsior MEGR-253.

Edit: seeing that you have the same regulator you might need to service the burner/flue.

You have an excellent point Ross. There's no need to fiddle with the regulator at all when camping at high elevations - unless you encounter a problem. Sometimes the fridges work there, sometimes not.

[Mike Lewis]

In late April / early May I camped near Santa Fe for ten days at 8700 feet altitude. Although I have a different model refrigerator, I had no problems with it or my other propane appliances. Got thirteen inches of snow, though..

[sumac.rhus]

By my question it will probably be obvious that I know nothing about the regulators.... but... could a person have two regulators -one set for high elevation, and another not... and switch them out accordingly? ...or do they have to be set in conjunction with being on the tanks, and lose the setting when removed?

[rbryan4]

Originally Posted by sumac.rhus

By my question it will probably be obvious that I know nothing about the regulators.... but... could a person have two regulators -one set for high elevation, and another not... and switch them out accordingly? ...or do they have to be set in conjunction with being on the tanks, and lose the setting when removed?

The setting is just a screw position. You could indeed have two regulators, one set at the standard 11" of WC pressure, and one set to lower pressure. But, I would think changing out the regulators would be more of a bother than simply adjusting the one. Once you've measured it with a manometer, it would be quick and easy to know the adjustment needed to set it again. All of this of course is assuming an adjustment is needed at all. We have camped as high as 9100 feet and the fridge worked ok with no regulator adjustment.

[Brian B-P]

Originally Posted by sumac.rhus

... could a person have two regulators -one set for high elevation, and another not... and switch them out accordingly? ...or do they have to be set in conjunction with being on the tanks, and lose the setting when removed?

If you had to switch that would work fine. They are not really supposed to be adjustable (so in some models there is no readily accessible adjustment screw), but any adjustment is not dependent on other components such as the tanks so once it's set it should stay at that setting.

If you ensure that both inlet and outlet connections are flare or inverted flare, and the brass adapters are left screwed into each regulator, regulators can be swapped with just wrenches, no sealant, and no pipe threads involved. Usually the inlets are 1/4" inverted flare and the outlet is 3/8" flare. For instance, the MEGR-253 (like the MEGR-253H and MEGR-253L) comes with adapters in the inlets for the 1/4" inverted flare ends of common pigtail hoses, but just has a pipe thread outlet so that would need an adapter and a matching hose to the trailer.

I would put some indicator on each regulator of the setting, such as markings with paint pen, or just a colour-coded cable tie around a suitable part. I would not suggest painting the whole regulator, because coloured bodies of regulators have specific meanings.

[sumac.rhus]

Thanks!
I kinda like the idea of having a "standard" regulator and "high altitude" one. I live in the Inland Northwest - lot of altitude range. Also love the San Juan and Gulf Islands, as well as Utah and Colorado.

[ThomasG]

I recently had this problem in my 2017 5.0 TA with a DM2663 refrigerator. I was camped at 8900 ft in the Timber Creek campground in the Rocky Mountain National Park. The refrigerator had trouble lighting and wouldn't stay lit. Also, the sound of the refrigerator flame was noticeably louder that it was at lower altitudes. The refrigerator worked fine at my previous campsite at 7500 ft. My trailer did come with the MEGR-253 regulator.

After reading this thread I realized the problem was most likely too much LP pressure for my current altitude.

I didn't have the parts to build a manometer, so I just adjusted the regulator to lower the pressure until the refrigerator started working reliably (counting the turns on the regulator adjustment as I did it). I adjusted the pressure back up after I got to a lower altitude.

After I got home I built a manometer similar to the one in the video shown earlier in this thread. The LP pressure was about 12 inches at that point. This was most likely due to my inprecise adjustments without a manometer. I easily adjusted it to 11 inches with my new manometer.

Someone suggested having two regulators and switching between them depending on your altitude. I like this idea, but it seems very messy to implement (lots of LP tubing, Ts, valves, etc. all in a small space). Does anyone know if it is possible to add a LP valve in front of the refrigerator that could be adjusted to reduce the pressure when needed? I know a valve isn't a regulator, but it seems it would work, be cheap and fairly easy to install. A specific recommendation for a valve would be appreciated if this seems like a reasonable thing to do.

[Brian B-P]

Originally Posted by ThomasG

Does anyone know if it is possible to add a LP valve in front of the refrigerator that could be adjusted to reduce the pressure when needed? I know a valve isn't a regulator, but it seems it would work, be cheap and fairly easy to install.

I don't think that it would work very well. Most of the pressure drop from the regulated level (11" WC or whatever) to ambient pressure needs to be across the orifice at the burner for it to work properly. A restriction (partially closed valve) upstream of the orifice would have the same effect as a long run of plumbing with restrictive fittings (elbows), and I haven't noticed people needing to change regulator settings or orifices to suit the plumbing run.

Changing the orifice would make sense, but would likely be more hassle than swapping properly mounted regulators.

Originally Posted by ThomasG

A specific recommendation for a valve would be appreciated if this seems like a reasonable thing to do.

If you want to try it, common quarter-turn valves available at plumbing stores and building centres are often rated for propane. These valves came up in a recent discussion:
I'd like to buy your Campfire in a Can for the original price. (jump to post #51 if you want to save time)
Some devices use these valves for manual control of flame size.

[ThomasG]

Originally Posted by Brian B-P

I don't think that it would work very well. Most of the pressure drop from the regulated level (11" WC or whatever) to ambient pressure needs to be across the orifice at the burner for it to work properly. A restriction (partially closed valve) upstream of the orifice would have the same effect as a long run of plumbing with restrictive fittings (elbows), and I haven't noticed people needing to change regulator settings or orifices to suit the plumbing run.

Changing the orifice would make sense, but would likely be more hassle than swapping properly mounted regulators.


If you want to try it, common quarter-turn valves available at plumbing stores and building centres are often rated for propane. These valves came up in a recent discussion:
I'd like to buy your Campfire in a Can for the original price. (jump to post #51 if you want to save time)
Some devices use these valves for manual control of flame size.

Thanks Brian. That is exactly what I needed (both your advice and the valve). I'll put it on my list of things to do after all of the other more important upgrades and modifications that I already have planed.

[burnauk]

Are your propane tanks new? If so, they may not have been properly purged of the nitrogen or air the mfg tested them with. Any 'unwanted gas' mixing with the propane in your tank will cause the problem exactly as described, especially at high elevations