Do you travel with the refrigerator on?

[Michael.Chadwick]

I drive with it on propane, never a problem, been through the rockies twice thats 10% plus but all works.........id worry more about braking as someone stated lol

[bevans]

Many sources say it is both dangerous and illegal to drive with the propane on. Check it out.

[gbaglo]

Originally Posted by bevans

Many sources say it is both dangerous and illegal to drive with the propane on. Check it out.

That is absolutely not true.
We've had this discussion before and some of us have done research ( not just Google ).
Following is a response I got from Transport Canada and Jim Bennett got responses from DMVs across Canada. None prohibited travelling with propane refrigerator on.


Re: running refrigerator on road - Transport Canada response
Hi Glenn:

Your question was forwarded to the Inspector Education and Public Awareness Division of the Transportation of Dangerous Goods (TDG) Directorate within Transport Canada for response.

The answer is yes, under the Federal Transportation of Dangerous Goods (TDG) Regulations the refrigeration system may be used while the RV trailer is in transit. However, we suggest that you contact the province in which you intend to operate your vehicle to verify if they have any additional requirements. For instance, you may not be able to operate your system in a tunnel or you may be limited to two cylinders. Also, you may face other limitations when you’re on a ferry. Finally, we suggest that you verify with your trailer manufacturer to verify their position on this subject.

[John in Santa Cruz]

Originally Posted by bdornbush

I recently traveled with my trailer across and back across the Sierra Nevada range in California. I always run the refrigerator on 12v while traveling and my Jeep Grand Cherokee plus solar panel keeps the battery charged. On my last trip, I noticed that the trailer battery didn't recharge any but it did not discharge either. And that was while crossing through the Ebbetts Pass which has some parts that are less than a full two lanes wide and a grade of 24% !! I was going up the steep part and the Jeep pulled us up with no problem. The refrigerator was cool at 36 degrees F when we arrived at our campsite. Fortunately, the traffic is fairly light and we didn't pass any large trucks or others towing trailers.

the key issue is the wire gauge from the tow vehicle alternator to the trailer connector, and from the trailer connector to the trailer battery. Lets say the vehicle and trailer both use 12 gauge, and in the case of my Tacoma (16 feet long) and E21 (21 feet long) there's about 40 feet of wire in the positive path and another 25 feet of wire on the trailer side on the negative path (the tow outlet on the truck was grounded to chassis which we will assume is really really fat gauge).

so the fridge is like 15 amps in DC mode, and we have 65 feet of 12 gauge. 1000 feet of AWG 12 copper wire is 1.588 ohms, so 65 feet is 0.10 ohms (rounded to 1%). 15 amps at 0.1 ohms is a 1.5 volt drop, so instead of the 14.2V I measure at my vehicles alternator when its in fast charge mode, only 12.7 volts is making it to the battery, and when the vehicle alternator falls back to 13.6V 'maintenance' after awhile (I measured the Tacoma doing this exact thing), then the battery only sees 12.1V and therefore is discharging to maintain that 15A on the distributor. Its even worse if there's any resistance at the 7-blade trailer connector, either on the +12 or ground pins, corroded brass can be several times 0.1 ohms.

I think I calculated that I would have needed to rewire both the truck and the trailer with 8 gauge for this to work robustly under all conditions.

[Iowa Dave]

Originally Posted by bevans

Many sources say it is both dangerous and illegal to drive with the propane on. Check it out.

I would much rather travel with my refrigerator set to propane than to enter a public school where masks are not required or have a drink in a crowded bar. Oh wait, I do travel with propane on and running the refrigerator and no I’m not begging for the Covid 19 to take me out. Even though our governor, who ranks 50th out of 50 in Covid 19 Pandemic performance says it’s ok for me to do so.
Iowa Dave

[Dave&Kathie]

We have traveled thousands of miles in all kinds of weather with the frig on propane. The only time we turn it off is for ferries and tunnels that require it. If it's during hot weather we keep a few ziploc bags of crushed ice in the freezer and throw them in the frig if the temps go up. We have a temperature sensor in the frig and the main unit we put in the car while we are on the road. It has worked great over the years.

Kathie

[Raider47]

Originally Posted by John in Santa Cruz

the key issue is the wire gauge from the tow vehicle alternator to the trailer connector, and from the trailer connector to the trailer battery. Lets say the vehicle and trailer both use 12 gauge, and in the case of my Tacoma (16 feet long) and E21 (21 feet long) there's about 40 feet of wire in the positive path and another 25 feet of wire on the trailer side on the negative path (the tow outlet on the truck was grounded to chassis which we will assume is really really fat gauge).

so the fridge is like 15 amps in DC mode, and we have 65 feet of 12 gauge. 1000 feet of AWG 12 copper wire is 1.588 ohms, so 65 feet is 0.10 ohms (rounded to 1%). 15 amps at 0.1 ohms is a 1.5 volt drop, so instead of the 14.2V I measure at my vehicles alternator when its in fast charge mode, only 12.7 volts is making it to the battery, and when the vehicle alternator falls back to 13.6V 'maintenance' after awhile (I measured the Tacoma doing this exact thing), then the battery only sees 12.1V and therefore is discharging to maintain that 15A on the distributor. Its even worse if there's any resistance at the 7-blade trailer connector, either on the +12 or ground pins, corroded brass can be several times 0.1 ohms.

I think I calculated that I would have needed to rewire both the truck and the trailer with 8 gauge for this to work robustly under all conditions.

Would a higher amperage alternator on the tow vehicle effect the rate of battery charge, or is the wiring the limiting factor?

[sunrisetrucker]

Originally Posted by bevans

Many sources say it is both dangerous and illegal to drive with the propane on. Check it out.

Originally Posted by gbaglo

That is absolutely not true.
We've had this discussion before and some of us have done research ( not just Google ).
Following is a response I got from Transport Canada and Jim Bennett got responses from DMVs across Canada. None prohibited travelling with propane refrigerator on.


Re: running refrigerator on road - Transport Canada response
Hi Glenn:

Your question was forwarded to the Inspector Education and Public Awareness Division of the Transportation of Dangerous Goods (TDG) Directorate within Transport Canada for response.

The answer is yes, under the Federal Transportation of Dangerous Goods (TDG) Regulations the refrigeration system may be used while the RV trailer is in transit. However, we suggest that you contact the province in which you intend to operate your vehicle to verify if they have any additional requirements. For instance, you may not be able to operate your system in a tunnel or you may be limited to two cylinders. Also, you may face other limitations when you’re on a ferry. Finally, we suggest that you verify with your trailer manufacturer to verify their position on this subject.

Thank you Glenn. I'm starting to get tired of that same misinformation being repeated again and again.

[John in Santa Cruz]

Originally Posted by Raider47

Would a higher amperage alternator on the tow vehicle effect the rate of battery charge, or is the wiring the limiting factor?

its the wire resistance. I verified that with the fridge on, and engine running, I wsa seeing 14.2 or 14.4V at the vehicle battery so the alternator could easily handle the output.

the wire resistance causes a voltage drop proportional to the current (ohms * amps == voltage drop), and the resistance itself is proportional to the wire gauge and length, with the resistance of any connections added in.

[HABBERDABBER]

Others may chime in, more correctly than me, but wire gauge is a most significant factor in moving DC current. Think of it as a hose. Bigger the hose, the more juice coming through. You could have Niagara Falls as your source, but if you have a small hose, well, it doesn't get much more water where you want it.

[Tworainy]

With my new Nova Kool fridge, it is DC by default when on the road. Ran it for 4 full hot days without any hookups and it was still cold! No solar, no AC, no propane. Going on our maiden voyage with it soon, and will report our experience on the forum.

[Meandering Minstrel]

We always travel with the fridge on if it's already chilled and "filled" up. We have a tow vehicle with a really good alternator so we usually travel with it on DC. But also use propane if we're going to make a lot of long stops.

[John in Santa Cruz]

Originally Posted by Tworainy

With my new Nova Kool fridge, it is DC by default when on the road. Ran it for 4 full hot days without any hookups and it was still cold! No solar, no AC, no propane. Going on our maiden voyage with it soon, and will report our experience on the forum.

thatsa compressor fridge, and probably uses a lot less than 15 amps constantly.

[Centex]

Originally Posted by John in Santa Cruz

thatsa compressor fridge, and probably uses a lot less than 15 amps constantly.

On the order of 5 A @ nominal 12VDC when the compressor runs, constant few milliamps for the control system.

Nova Kool suggests a 15A fuse at the 12VDC power source with 15A ampacity for the power feed wire to the unit (half that if one has a 24VDC power source). Maybe that to accommodate a bit of compressor-start current spike, I'm not sure. The compressor is variable-speed depending on thermostat setting / demand, drawing less current at lower than max speed.

Interestingly, all of their units auto-sense either 12 or 24VDC (a marine application accommodation?) and will run on either seamlessly, drawing lower metered amps @ 24VDC of course.

AC 'shore power' operation is an extra-cost option, if ya go for that the unit auto toggles to AC whenever it is available, and back to DC when it's lost.

A very efficient electric reefer / freezer, but nope, no LP option for those at all.

[Langley Barb]

No. We precool the refrigerator on the coldest setting the day before, load it up, and close it. We put freezer packs in the freezer to help keep it cold as if it were a cooler. We don’t open it until we get to our destination. It keeps things cold very efficiently like a good cooler. The Escape folks told us never to run it on electricity while driving because it would suck the vehicle battery dead if we ever stopped and parked for a rest for a while. In general we prefer to drive with the propane valves turned off, so we don’t run the fridge at all while driving. Works for us!

[Perry Butler]

When we had our 2003 Odyssey I wired a separate plug with an 8 gage wire to the converter. We could run our fridge and charge the battery. Only had to make sure I switched to LP when in the campground. Worked great, until . . . Murphy reared his ugly head. That's why we now run the LP when traveling down the road. Haven't had dead batteries since.

Enjoy,

Perry

[TZBrown]

Originally Posted by Raider47

Would a higher amperage alternator on the tow vehicle effect the rate of battery charge, or is the wiring the limiting factor?

I have a truck with a snowplow package installed, that includes 2 100A alternators.
I can make lots of power, but with #10 wire through the truck to the rear, and #10 in the trailer not enough amps get to the batteries using DC for the fridge.

Generally the alternator output is regulated by the vehicle batteries which are closest to the alternator, limiting the output somewhat.
The charge wires are for sure the limiting factor to the trailer.

[John in Santa Cruz]

Originally Posted by TZBrown

I have a truck with a snowplow package installed, that includes 2 100A alternators.
I can make lots of power, but with #10 wire through the truck to the rear, and #10 in the trailer not enough amps get to the batteries using DC for the fridge.

Generally the alternator output is regulated by the vehicle batteries which are closest to the alternator, limiting the output somewhat.
The charge wires are for sure the limiting factor to the trailer.

to be technical, its not enough VOLTS are making it to the trailer battery when the system is under the high amperage load of the DC reefer.

[alanmalk]

Originally Posted by John in Santa Cruz

to be technical, its not enough VOLTS are making it to the trailer battery when the system is under the high amperage load of the DC reefer.

Just to confirm John's measurements: I get essentially the same readings with my 2014 Tacoma and E'21.

The standard alternator can supply plenty of amps IF the load requires them. But the miles of skinny wire (2 ways) between the alternator and fridge prevent the power from reaching where it is really needed while towing with the fridge on 12V. The alternator is essentially unaware of the load required.

If powering the fridge on 12V while towing becomes a high priority, there are pricey gadgets that will boost the voltage and overcome the voltage drop due to skinny wires.
--
Alan

[Tworainy]

Originally Posted by Centex

On the order of 5 A @ nominal 12VDC when the compressor runs, constant few milliamps for the control system.

Nova Kool suggests a 15A fuse at the 12VDC power source with 15A ampacity for the power feed wire to the unit (half that if one has a 24VDC power source). Maybe that to accommodate a bit of compressor-start current spike, I'm not sure. The compressor is variable-speed depending on thermostat setting / demand, drawing less current at lower than max speed.

Interestingly, all of their units auto-sense either 12 or 24VDC (a marine application accommodation?) and will run on either seamlessly, drawing lower metered amps @ 24VDC of course.

AC 'shore power' operation is an extra-cost option, if ya go for that the unit auto toggles to AC whenever it is available, and back to DC when it's lost.

A very efficient electric reefer / freezer, but nope, no LP option for those at all.

2.2 Amps only...and that's only when it needs to cool. Quite remarkable, actually. And a lot less expensive to purchase!