Running the fridge while you tow

[babock]

Originally Posted by DrakeGuy

Well now I thought that 3-way fridges shouldn't be used when towing because the amonia cooling system has to be within three degrees of level or it could fail, and possibly catch fire?

Nothing to do with catching fire.


While towing the jostling of the trailer/RV keeps the ammonia from pooling.

[Chuck_S]

3° came from where? If the camper is level enough to sleep in it's level enough for the refrigerator -- when parked. On the road the level doesn't matter as the liquids are all getting sloshed around.

-- Chuck

[Chuck_S]

EDIT: So I looked up the specs for my Dometic 2652. It consumes max 1501BTU/hr on propane and 440W/hour on 120V. Guess what? 440W is equal to 1501 BTU so the energy used for both propane and 120V is IDENTICAL. So much for the theory that propane works better 120V.

Not so with my Dometic 2652 (same model). Here's the data plate. The refrigerator pulls 2.7 amps at 120vAC or 324 watts (not 440) which is 1100 BTU compared to the 1500 BTU on LP. 440 watts is indeed 1500 BTU but my refrigerator only puts out 324 watts on AC. And in high summer heat the voltage at many campgrounds doesn't get as high as 120vAC


Surprised yours is different.

-- Chuck

[glen1971]

I found a few notes on it, on the net. Draw your own conclusions, but it isn't necessary or even legal in some places..

From Transport Canada:
A person must not handle, offer for transport or transport dangerous goods in a means of containment that is required or permitted by this Part unless the means of containment is designed, constructed, filled, closed, secured and maintained so that under normal conditions of transport, including handling, there will be no release of the dangerous goods that could endanger public safety.

From one site:
Don’t drive with your LP valves open. The risk is more from being in an accident where LP goes everywhere you don’t want it and then ignites and explodes, versus just sitting there. It’s your choice, but if you clobbered, or rolled, or even go into a high wind and are upended an open LP tank can be bad news.

From another:
Although LPG is a very safe fuel, all sources of ignition should be switched off when you are traveling with your RV. This includes closing the main valve on the tank. There is no sense in having the super safe DOT tank and then leaving the valve open! (Your fridge by the way, once cooled, will retain sufficient temperature for about 12 hours without a source of fuel; so no worries about your food spoiling while driving for the day).

FWIW, here is a link to Good Sam and the rules by state/province. Some specify that you can't have an open valve while driving.
https://www.goodsam.com/article/defa...icleID=2377513

[Chuck_S]

The sky is NOT falling (your link):

LP-GAS PROHIBITED:
Maryland/Baltimore: Baltimore Harbor and Fort McHenry (I-95) tunnels. Alternate route for RVs with propane over the Francis Scott Key Bridge is I-695. Massachusetts/Boston Harbor: All. New York/East River: Between Manhattan and Brooklyn: Brooklyn Battery Tunnel. Between Manhattan and Queens: Queens Midtown Tunnel. New York and New Jersey/Hudson River: Between Manhattan and Jersey City: Holland Tunnel. Between Manhattan and Fort Lee: Lower level George Washington Bridge (I-95 South) and George Washington Bridge Expressway. Lower level Verrazano Narrows Bridge. Between Manhattan and Weehawken: Lincoln Tunnel.
LP-GAS RESTRICTIONS:
Virginia/Chesapeake Bay Bridge/Tunnel: RVs equipped with ICC-approved compressed cooking tanks not exceeding two 45-pound capacity tanks (or two permanently mounted containers with maximum total capacity of 200 pounds) may cross the facility provided that, in the opinion of the toll collector or police sergeant after inspection, the tanks are completely shut off and securely attached. Texas/Houston Ship Channel: Washburn Tunnel between Pasadena and Galena Park: Maximum of two 7½-gallon containers (30 pounds gas each) or one 10-gallon container (40 pounds gas) of DOT (ICC)-approved type, with shutoff valve at discharge opening. Valve must be closed when in tunnel. LP-gas as vehicle fuel prohibited. 7½-gallon containers (30 pounds gas each) or one 10-gallon container (40 pounds gas) of DOT (ICC)-approved type, with shutoff valve at discharge opening. Valve must be closed when in tunnel. LP-gas as vehicle fuel prohibited.

[daverobenolt]

Originally Posted by glen1971

I found a few notes on it, on the net. Draw your own conclusions, but it isn't necessary or even legal in some places..



From Transport Canada:

A person must not handle, offer for transport or transport dangerous goods in a means of containment that is required or permitted by this Part unless the means of containment is designed, constructed, filled, closed, secured and maintained so that under normal conditions of transport, including handling, there will be no release of the dangerous goods that could endanger public safety.



From one site:

Don’t drive with your LP valves open. The risk is more from being in an accident where LP goes everywhere you don’t want it and then ignites and explodes, versus just sitting there. It’s your choice, but if you clobbered, or rolled, or even go into a high wind and are upended an open LP tank can be bad news.



From another:

Although LPG is a very safe fuel, all sources of ignition should be switched off when you are traveling with your RV. This includes closing the main valve on the tank. There is no sense in having the super safe DOT tank and then leaving the valve open! (Your fridge by the way, once cooled, will retain sufficient temperature for about 12 hours without a source of fuel; so no worries about your food spoiling while driving for the day).



FWIW, here is a link to Good Sam and the rules by state/province. Some specify that you can't have an open valve while driving.

https://www.goodsam.com/article/defa...icleID=2377513

12volts only way to go when traveling! Why not? I’ve been doing it for 10+ years. No issue and food stays between 39°-42° regardless of outside temperature. DC voltage is free and safe.

[daverobenolt]

Originally Posted by daverobenolt

12volts only way to go when traveling! Why not? I’ve been doing it for 10+ years. No issue and food stays between 39°-42° regardless of outside temperature. DC voltage is free and safe.

The only time I used LP was when we stayed at a lodge overnight . I disconnected trailer and parked in the parking lot away from all other vehicles and switched to LP. They use very little LP but 12 volts works just as well, at least that my experience.

[babock]

Originally Posted by daverobenolt

12volts only way to go when traveling! Why not? I’ve been doing it for 10+ years. No issue and food stays between 39°-42° regardless of outside temperature. DC voltage is free and safe.

If your fridge is getting over 40°, its not working correctly.

[babock]

Originally Posted by Chuck_S

Not so with my Dometic 2652 (same model). Here's the data plate. The refrigerator pulls 2.7 amps at 120vAC or 324 watts (not 440) which is 1100 BTU compared to the 1500 BTU on LP. 440 watts is indeed 1500 BTU but my refrigerator only puts out 324 watts on AC. And in high summer heat the voltage at many campgrounds doesn't get as high as 120vAC


Surprised yours is different.

-- Chuck

Mine is 11 years newer than yours.

[babock]

Originally Posted by Chuck_S

Not so with my Dometic 2652 (same model). Here's the data plate. The refrigerator pulls 2.7 amps at 120vAC or 324 watts (not 440) which is 1100 BTU compared to the 1500 BTU on LP. 440 watts is indeed 1500 BTU but my refrigerator only puts out 324 watts on AC. And in high summer heat the voltage at many campgrounds doesn't get as high as 120vAC


Surprised yours is different.

-- Chuck

Mine is 11 years newer than yours. Maybe you could replace yours with what comes with the current model! When I am in full sun, I can run mine off my inverter with my solar during the day. Works just fine and keeps the fridge at 33°. In fact, it cycles on and off so there are plenty of BTUs being supplied by the AC heater.

[rockfordroo]

Originally Posted by babock

EDIT: So I looked up the specs for my Dometic 2652. It consumes max 1501BTU/hr on propane and 440W/hour on 120V. Guess what? 440W is equal to 1501 BTU so the energy used for both propane and 120V is IDENTICAL. So much for the theory that propane works better 120V.

Originally Posted by Chuck_S

Not so with my Dometic 2652 (same model). Here's the data plate. The refrigerator pulls 2.7 amps at 120vAC or 324 watts (not 440) which is 1100 BTU compared to the 1500 BTU on LP. 440 watts is indeed 1500 BTU but my refrigerator only puts out 324 watts on AC. And in high summer heat the voltage at many campgrounds doesn't get as high as 120vAC


Surprised yours is different.

-- Chuck

Originally Posted by babock

Mine is 11 years newer than yours. Maybe you could replace yours with what comes with the current model! When I am in full sun, I can run mine off my inverter with my solar during the day. Works just fine and keeps the fridge at 33°. In fact, it cycles on and off so there are plenty of BTUs being supplied by the AC heater.

11 years newer doesn't mean anything. Still 325 watts (1100 BTUs) per DM262 manual dated Dec, 2017, fresh off the Dometic website. (See last line of spare parts table on page 16). I'm pretty sure a higher wattage change would have involved a model number change.

[babock]

I have measured mine with the inverter running. Over 400W. 35A DC x 13.5V = 472W minus inverter efficiency is pretty close to the 440W Spec. If you have never measured, you don't even know.


I will measure the AC amps with a kill-a-watt meter when I get back into town.

[rockfordroo]

Originally Posted by babock

I have measured mine with the inverter running. Over 400W. 35A DC x 13.5V = 472W minus inverter efficiency is pretty close to the 440W Spec. If you have never measured, you don't even know.


I will measure the AC amps with a kill-a-watt meter when I get back into town.

You're right, I haven't measured, I assume the manufacturer knows what he's selling. And YOU stated "I looked up the specs." Now your claiming some measurement.

I'd like know what "specs" you looked up. So please show them to us.

I'm skeptical of your measurement. Put an ammeter on the wire to the heater and I'll be a believer. (Include a pic, please.)

[babock]

Originally Posted by rockfordroo

You're right, I haven't measured, I assume the manufacturer knows what he's selling. And YOU stated "I looked up the specs." Now your claiming some measurement.

I'd like know what "specs" you looked up. So please show them to us.

I'm skeptical of your measurement. Put an ammeter on the wire to the heater and I'll be a believer. (Include a pic, please.)

I will definitely include a pic when I measure it. I already measured it through the inverter.


Bottom line, if a fridge does not work properly on 120VAC, there is something wrong with the fridge. When I go on a trip, I pre chill the fridge on 120VAC. I can get 33 degrees in the fridge while its 100 degrees out. If you can't do that, troubleshoot your fridge.

[rockfordroo]

Originally Posted by babock

I will definitely include a pic when I measure it. I already measured it through the inverter.


Bottom line, if a fridge does not work properly on 120VAC, there is something wrong with the fridge. When I go on a trip, I pre chill the fridge on 120VAC. I can get 33 degrees in the fridge while its 100 degrees out. If you can't do that, troubleshoot your fridge.

So I'm guessing there weren't any "specs."

[babock]

Originally Posted by rockfordroo

So I'm guessing there weren't any "specs."

You guess wrong! I am on a trip so difficult to find them at the moment. Poor internet reception while I am on a boat.