Residential fridge powered while towing?

[Bill M]

We bought this rig new (2020 Solitude S class 2930RL-R) and only had to pull it a few miles to our site. Now we are contemplating the long journey north and wonder how the fridge will be powered along the way.

I'm assuming the following:

When we disconnect from shore power the fridge will automatically start drawing power from the batteries via the inverter.

While towing this will still be the case but the truck electrical system will replenish the house batteries along the way.

When stopped but still connected electrically to the rig the truck battery will join the house batteries to keep the fridge running.

When disconnected from the truck but not on shore power the house batteries will continue to supply the fridge until depleted or recharged.

Once reconnected to shore power the fridge will automatically draw from that and not the batteries.

I'm not real sure about what happens while connected electrically to the truck both under way and with the motor off. Please let me know if Ii erred.

thanks

[ncitro]

We bought this rig new (2020 Solitude S class 2930RL-R) and only had to pull it a few miles to our site. Now we are contemplating the long journey north and wonder how the fridge will be powered along the way.

I'm assuming the following:

When we disconnect from shore power the fridge will automatically start drawing power from the batteries via the inverter.
Correct

While towing this will still be the case but the truck electrical system will replenish the house batteries along the way.
Yes, however I would not expect it to keep up. On my rig I get about 10 amps max charging from the truck, the refrigerator will draw significantly more than that. How much more will depend on the temperature you are towing in, but you will want to monitor your battery level throughout the trip to ensure you do not deplete the batteries too far, or worse cause the fridge to lose power.

When stopped but still connected electrically to the rig the truck battery will join the house batteries to keep the fridge running.
On my Ford, the charging wire in the seven pin connector is only live when the ignition is running, to prevent the RV from drawing down the truck battery. I cannot speak to your Chevy, but I would expect the same. Easy to test and make know however.

When disconnected from the truck but not on shore power the house batteries will continue to supply the fridge until depleted or recharged.
Correct

Once reconnected to shore power the fridge will automatically draw from that and not the batteries.
Correct

I'm not real sure about what happens while connected electrically to the truck both under way and with the motor off. Please let me know if Ii erred.
See above.

thanks

I will try to help out where I can here, but some of the answers may depend on your specific equipment.

[howson]

We bought this rig new (2020 Solitude S class 2930RL-R) and only had to pull it a few miles to our site. Now we are contemplating the long journey north and wonder how the fridge will be powered along the way.

I'm assuming the following:

When we disconnect from shore power the fridge will automatically start drawing power from the batteries via the inverter.

While towing this will still be the case but the truck electrical system will replenish the house batteries along the way.

When stopped but still connected electrically to the rig the truck battery will join the house batteries to keep the fridge running.

When disconnected from the truck but not on shore power the house batteries will continue to supply the fridge until depleted or recharged.

Once reconnected to shore power the fridge will automatically draw from that and not the batteries.

I'm not real sure about what happens while connected electrically to the truck both under way and with the motor off. Please let me know if Ii erred.

thanks

This thread may be of some help: https://gdrvowners.com/forum/operati...g-refrigerator

IMHO it is critical to know the battery's charge level. Seriously consider installing something like a Victron BMV-712. Expensive, but worth every penny. The ability to look at the battery status on your phone (via bluetooth) makes it super easy to monitor.

[Yoda]

Another thing that would help while traveling is have frozen milk containers available to put in the fridge while traveling. Dry Ice also works very well.

[JBill9694]

Our SOP is to turn the frig off when we travel. So far the frig has been able to maintain decent internal temperature with no spoilage or noticeable thawing of frozen food during the six to seven hours between undocking and docking.

[howson]

Our SOP is to turn the frig off when we travel. So far the frig has been able to maintain decent internal temperature with no spoilage or noticeable thawing of frozen food during the six to seven hours between undocking and docking.

Your process may be safe, but have you actually measured the internal temperatures? My question is after reading this from my fellow moderator, TucsonJim : https://gdrvowners.com/forum/operati...d-temperatures

[Bill M]

Thanks everyone for commenting on this string; this forum is a real asset.

We bought our truck off the lot and it is equipped with a snow plow package (not that I intend to use it for plowing it just came that way). The dealer told me the max output of the alternator is 220 amps. Of course it will only put out as many amps as being pulled. According to the nameplate on the fridge the amp draw is 3.0 (AC). I found a formula to calculate the amount of DC amps needed to power an AC amp load though an inverter: about 11 to 1.

So in this case about 33 amps. The alternator is powering every other load in the truck (like the AC) at the same time but it seems there should be plenty of margin for powering the fridge while towing. Or am I wishful thinking?

btw Howard did you (or would you recommend a layman) do a self install on the battery monitor?

[ncitro]

Thanks everyone for commenting on this string; this forum is a real asset.

We bought our truck off the lot and it is equipped with a snow plow package (not that I intend to use it for plowing it just came that way). The dealer told me the max output of the alternator is 220 amps. Of course it will only put out as many amps as being pulled. According to the nameplate on the fridge the amp draw is 3.0 (AC). I found a formula to calculate the amount of DC amps needed to power an AC amp load though an inverter: about 11 to 1.

So in this case about 33 amps. The alternator is powering every other load in the truck (like the AC) at the same time but it seems there should be plenty of margin for powering the fridge while towing. Or am I wishful thinking?

btw Howard did you (or would you recommend a layman) do a self install on the battery monitor?

Unfortunately it’s wishful thinking. Due to the way the trailer circuitry is wired and the size of the wiring the most any of us have seen traveling from the truck to be trailer is 10 amps.

I have done a few battery monitor installs, and while I am familiar with electricity and electronics it is pretty straightforward even for a layman. The Victron unit in particular is really easy, and the mobile app makes keeping an eye on charging current and battery capacity while towing much easier.

I went down the rabbit hole of increasing charging from the truck to keep up with the inverter draw (I installed a residential unit so I do not have the option for propane operation), and decided to install solar instead so I would have that option when dry camping. I am now considering upgrading the charging via the Renogy DC to DC charger. howson has a great writeup on it.

[howson]

Thanks everyone for commenting on this string; this forum is a real asset.

We bought our truck off the lot and it is equipped with a snow plow package (not that I intend to use it for plowing it just came that way). The dealer told me the max output of the alternator is 220 amps. Of course it will only put out as many amps as being pulled. According to the nameplate on the fridge the amp draw is 3.0 (AC). I found a formula to calculate the amount of DC amps needed to power an AC amp load though an inverter: about 11 to 1.

So in this case about 33 amps. The alternator is powering every other load in the truck (like the AC) at the same time but it seems there should be plenty of margin for powering the fridge while towing. Or am I wishful thinking?

btw Howard did you (or would you recommend a layman) do a self install on the battery monitor?

As mentioned by ncitro , check out this thread: https://gdrvowners.com/forum/operati...e-battle-borns

Regarding the self-install of the battery monitor: the answer (I'm not a lawyer!) is "it depends". My entire adult life I've worked on electronics in one form or another, so the transition to working on large battery cables and reading wiring schematics was no big deal. I also enjoy torturing myself by tackling projects I've never attempted before (but usually get to do multiple times to get right). If you're a "do it yourself" guy and have a reasonable working knowledge of electricity, installing a battery monitor (Victron BMV-712 highly recommended) isn't too tough. If the terms DC, AC, amperage, wattage, gauge, terminal...and many, many, more seem like another form of the Greek language you might want to consider having it installed for you. But don't equate "installed for you" with meaning at the dealership--not too many of them I'd let touch my RV. Find a mobile RV mechanic or electrician you can trust and go from there.

[JBill9694]

Your process may be safe, but have you actually measured the internal temperatures? My question is after reading this from my fellow moderator, TucsonJim : https://gdrvowners.com/forum/operati...d-temperatures

After reading the other thread I have reconsidered our procedure. Our Norcold owners manual only says that the refer operation should be unaffected during travel, which seems to imply that it be left on. We will try leaving the refer own and running off the batteries next time we move, in about a month.

[ncitro]

After reading the other thread I have reconsidered our procedure. Our Norcold owners manual only says that the refer operation should be unaffected during travel, which seems to imply that it be left on. We will try leaving the refer own and running off the batteries next time we move, in about a month.

Not that my experience is a promise you will be fine, but prior to switching out to the residential fridge I towed many thousands of miles with my fridge running on propane with no issue.

[Cate&Rob]

Our Norcold owners manual only says that the refer operation should be unaffected during travel, which seems to imply that it be left on. We will try leaving the refer own and running off the batteries next time we move, in about a month.

Hi John,

There seems to be an "assumption" by Norcold that there will be enough battery reserve to accomplish this. You might want to do some basic calculations to determine how long you can expect your existing battery (bank?) power to last.

howson Howard or TucsonJim Jim can probably provide the best estimate of what the fridge will require in Ah, from the research that they have done.

Rob

[Bill M]

Unfortunately it’s wishful thinking. Due to the way the trailer circuitry is wired and the size of the wiring the most any of us have seen traveling from the truck to be trailer is 10 amps

Well 10 amps is better than none; at least the house batteries will have some power coming in. It did occur to me that there might be something that would prevent all those amps from flowing through the wiring and running the fridge at full power. I worried a little about overheating wires.

I'll take a look at the battery wiring and decide on the monitor installation. I'm comfortable doing it unless I see something that doesn't make sense. Then it's time to pick up the phone!

[ncitro]

Unfortunately it’s wishful thinking. Due to the way the trailer circuitry is wired and the size of the wiring the most any of us have seen traveling from the truck to be trailer is 10 amps

Well 10 amps is better than none; at least the house batteries will have some power coming in. It did occur to me that there might be something that would prevent all those amps from flowing through the wiring and running the fridge at full power. I worried a little about overheating wires.

I'll take a look at the battery wiring and decide on the monitor installation. I'm comfortable doing it unless I see something that doesn't make sense. Then it's time to pick up the phone!

Yeah the circuit is protected, so nothing will overheat or trip, you just will not get full alternator output to the batteries. Monitor install is really straightforward if you can follow instructions If you need a hand post on here, its a common install I would be someone on here might be in the same area as you.

[Tom in PGH]

Before we leave home, I freeze a couple of larger Tupperware-type plastic containers that are about 12x12x4” high. They fit, one on top of the other, in the freezer compartment. When we are ready to move, I leave the electric hooked up until the very last. Then, after we have pulled in the slides, my wife puts the ice containers on the second shelf of the fridge and we are ready to go as soon as we disconnect the electric. During the trip, any time we stop, I turn on the propane and the fridge. We usually stop for some groceries and a lunch that we have packed and eat in the truck. That gives the fridge about an hour or so to run, about mid-way through the day’s trip. There are times that the ice has kept things cold enough that the fridge doesn’t even run. As soon as we arrive at our next site, I again turn on the propane and fridge, before we do much else.

We also have a set of remote thermometers (one in the fridge and one in the freezer) and a display that I keep in the cab of the truck, so that we can keep an eye on things. With this process, we never have to open the fridge from the time we leave until well after we arrive and get set up. Once we are done setting up, we take the ice and put it back into the freezer, and it’s frozen solid in time for our next day of driving.

This seems to have worked well for us over the past year.