2005 Meridian 34H Refrigerator operation?

[Mongobird]

I had indications that the Norcold 1200 that came with this unit can run on AC, using the onboard RV inverter (a Dimensions 2000 W MSW device). Apparently there is also an option to run the refrigerator off DC, but apparently the OEM version supplied does not have that capability.

Wanting to run the refrigerator for limited time off electric, when the generator or shore power are not available, I tried running things off 12 V, no dice. Then I tried off 120 V with the inverter, no dice. Then I tried it off the generator, and it works.

So then I again called Winnebago support to find out what the OEM wiring was supposed to allow, and this time I was told that on that model, the refrigerator did not run off the inverter. Nor the clothes washer (makes sense, especially in dryer mode). Nor the water heater (makes sense).

They said that was for the 34H floor plan, and that there were other models and other floor plans which permitted the refrigerator to run off the inverter.

Since I would like to run the refrigerator off the inverter, at least for short periods, I will have to go digging to see what I need to switch, most likely in the 120V panel. If someone knows the scheme for handling what devices require shore power and/or generator power, that would be helpful to know, as it would save me time figuring it out and double checking my work.

Also, if anyone measured current draw, that would also save me measuring it. I suppose the key figure is the inverter draw to support the refrigerator when running the cooling cycle.

Thanks.

[Morich]

We've got some info on how it is designed to work when inverter is onboard but it doesn't show the frig on that lineup but instead working through a load shedder.
This info is copied from sheet two of this drawing:
http://www.winnebagoind.com/diagram/...ire_144817.pdf
Click the drawing for a better view or refer to it direct?
But what I see is the frig and water heater come off the load shedder but the inverter is fed by a different load center breaker, feeding a separate inverter load center and has no current connection for feeding the frig. If I remember on this coach both load centers are in the same closet/storage area??/
If you felt it desirable, the close location might let you run wire between the two load centers to swap the frig in on the inverter while swap one of the 15 amp circuit off the inverter to the load shedder.
That would take some thought as to what you wanted to share and how much you see using one group on battery versus using the other.

[Mongobird]

Interesting. I will have to bring up the diagram and supporting diagrams on my computer in the morning. But looking at my phone, it appears that the inverter drives the microwave and the three receptacle circuits. Not a lot of load. On the other hand, running the microwave with the refrigerator could push the inverter to the limit amp 2000 Watts. So I kind of understand why they did it.

What I don't understand is what drives the load shedder.

So it seems like this could work if one shut down the refrigerator while running the microwave.

Thanks.

[creativepart]

Besides the “can it work,“ perhaps you should think about this for a moment... running that fridge off that inverter will use a lot of amps. If you’re driving that would be okay, but just running off of your house batteries could be problematic.

Depending on your battery’s condition and how many you have you might find the fridge depletes you battery bank in very short order.

Is there some reason you’d rather use inverted 110v instead of propane?

Heating anything with electricity uses lots of amps and your RV fridge needs a lot of heat to cool itself. Which is why it works best on propane.

So be careful what you wish for.

[Mongobird]

Two use cases:

1. When doing a long drive with engine running, charging the batteries.

2. When in locations where propane is prohibited. May decide to allow tank to stay empty. Batteries desired for on the road or for transitionary times while connecting to shore power, etc.

[FIRE UP]

Originally Posted by Mongobird

I had indications that the Norcold 1200 that came with this unit can run on AC, using the onboard RV inverter (a Dimensions 2000 W MSW device). Apparently there is also an option to run the refrigerator off DC, but apparently the OEM version supplied does not have that capability.

Wanting to run the refrigerator for limited time off electric, when the generator or shore power are not available, I tried running things off 12 V, no dice. Then I tried off 120 V with the inverter, no dice. Then I tried it off the generator, and it works.

So then I again called Winnebago support to find out what the OEM wiring was supposed to allow, and this time I was told that on that model, the refrigerator did not run off the inverter. Nor the clothes washer (makes sense, especially in dryer mode). Nor the water heater (makes sense).

They said that was for the 34H floor plan, and that there were other models and other floor plans which permitted the refrigerator to run off the inverter.

Since I would like to run the refrigerator off the inverter, at least for short periods, I will have to go digging to see what I need to switch, most likely in the 120V panel. If someone knows the scheme for handling what devices require shore power and/or generator power, that would be helpful to know, as it would save me time figuring it out and double checking my work.

Also, if anyone measured current draw, that would also save me measuring it. I suppose the key figure is the inverter draw to support the refrigerator when running the cooling cycle.

Thanks.

Mongobird,
I'm wondering about the sentence I highlighted above. What exactly do you mean by that sentence? Your electrical system, wiring, inverter, fridge outlet, etc. is EXACTLY like ours. Yes, Winne (and Itasca) did not setup many of its coaches (at least our era diesel models) to have that one outlet, behind the fridge, to run off the inverter. I just went through all of this. I did what you're thinking of doing. That is, I *MacGyver'd* the wiring for that fridge outlet so it would be powered up by the inverter.

That *jury-rigg* took me all of about 20-25 minutes, just because I was lollygagging around. A good electrician could do it in less than five minutes.

But, here's something that could be very important in your thought process here. That Dimensions 2000 Watt Inverter/Charger you have is a MSW inverter. There are many electrical appliances out there, including some fridges and other types of circuitry, that do not play well with MSW inverters.

I know, because all the experimentation I just went through, proved it. But, there's big difference in what I was trying to do and what you are. I was trying to power up a brand new, Magic Chef 10.1 cu.ft. residential fridge with that MSW inverter. Actually, my inverter is the Magnum 2012ME MSW as, I replaced my 11 year old Dimensions unit years ago with it. But, never the less, my new fridge did not play well with that Magnum.

So, I just finished installing a KISAE 1000 Watt PSW Inverter WITH, built in transfer switch earlier this evening that is solely dedicated to running that fridge. And, it works like a charm.

Now, will your present RV fridge run on your MSW Dimensions 2000 watt Inverter/Charger, not a clue. But, setting that outlet behind the fridge to run on the inverter is a piece of cake. Let me know if you'd like to try it.
Scott

[Mongobird]

Originally Posted by FIRE UP

Mongobird,
I'm wondering about the sentence I highlighted above. What exactly do you mean by that sentence? Your electrical system, wiring, inverter, fridge outlet, etc. is EXACTLY like ours. Yes, Winne (and Itasca) did not setup many of its coaches (at least our era diesel models) to have that one outlet, behind the fridge, to run off the inverter. I just went through all of this. I did what you're thinking of doing. That is, I *MacGyver'd* the wiring for that fridge outlet so it would be powered up by the inverter.

That *jury-rigg* took me all of about 20-25 minutes, just because I was lollygagging around. A good electrician could do it in less than five minutes.

But, here's something that could be very important in your thought process here. That Dimensions 2000 Watt Inverter/Charger you have is a MSW inverter. There are many electrical appliances out there, including some fridges and other types of circuitry, that do not play well with MSW inverters.

I know, because all the experimentation I just went through, proved it. But, there's big difference in what I was trying to do and what you are. I was trying to power up a brand new, Magic Chef 10.1 cu.ft. residential fridge with that MSW inverter. Actually, my inverter is the Magnum 2012ME MSW as, I replaced my 11 year old Dimensions unit years ago with it. But, never the less, my new fridge did not play well with that Magnum.

So, I just finished installing a KISAE 1000 Watt PSW Inverter WITH, built in transfer switch earlier this evening that is solely dedicated to running that fridge. And, it works like a charm.

Now, will your present RV fridge run on your MSW Dimensions 2000 watt Inverter/Charger, not a clue. But, setting that outlet behind the fridge to run on the inverter is a piece of cake. Let me know if you'd like to try it.
Scott

Scott,

One must look at the mechanisms employed for refrigeration. For the refrigerant cycle supported by a compressor, there is an inductive load. Actually, and induction motor. Differences as little as 2 Hz can make the difference between running efficiently, and possibly not running at all, or running with a high compressor (motor) temperature.

In the ammonia absorption cycle, the energy input is not the mechanical operation of a compressor, but rather then density lift of the refrigerant, supported by heat. So my assumption is that the bulk of the energy required is fed into a resistive load.

But you bring up an interesting thought: a dedicated inverter for a given appliance. Not necessary, IMO, but in the case of let's say a microwave, it would be one way to handle the load of that appliance. And certainly not needed for a resistive hot water heater.

So I am going to reject your idea of a dedicated inverter as superfluous, at least in my case, but retain the novelty of the dedicated PSW inverter, perhaps for more sensitive electronics or other types of appliances.

Thanks.

[Morich]

Sounds like you are well on your way to do the study of which way to go but I might ask about the use of propane as I do not find it restricted. Are you in a location where there is a problem with that?
On the planning, I did clip off a good deal of the info on what the other circuits have on them, so that will certainly be a worth a look if you want more info on that, and it is also something that I wish I had for my RV. Different ages get different info and my year is not given any real schematics of wiring, so I have to guess. I would certainly like to print off a copy of that info and keep on the RV, for the times when I might find something failed and be able to quickly sort the cause, rather than wait and work around something not working.
Much of how we need to set up depends on personal issues like what we use or not. There is an outlet listed as "hair drier" on one of the other circuits and that might be one that certainly would not have to stay on that circuit at my RV! I have never used one and my wife has adapted to not using one long ago when we camped with kids as it was just too much trouble!
Look, learn, adapt as needed?

[Mongobird]

There are tunnels and some bridges where propane is restricted. Normally, it just needs to be shut off, but in a few cases it is not permitted and it is easiest to simply have empty tanks.

A good metro example is Baltimore.

[creativepart]

You are aware that a cold fridge with cold contents, when not being used, will certainly keep things cold for the duration of traversing any tunnel in the world... right?

Good luck having an empty propane tank without going to lengths to evacuate the gas.

Regardless of these things it’s obvious that you wish to run your propane/electric RV fridge on inverter which should be an easy change for a person with electrical Wiring knowledge.

Don’t forget to also research your current battery bank’s status and capacity.

[Morich]

Originally Posted by Mongobird

There are tunnels and some bridges where propane is restricted. Normally, it just needs to be shut off, but in a few cases it is not permitted and it is easiest to simply have empty tanks.

A good metro example is Baltimore.

I know of tunnels which restrict propane but I was thinking of it as a longer term thing like where you were camped and might not be allowed to use propane. I thought perhaps you were reading the rules as more restrictive than meant to be.
I'm always interested in what we might find in different locations, so can you clue us in on what Baltimore has on propane use?
From the state regs, it looks like propane is only restricted in two tunnels, so I would look at using the alternate route on the odd occasions I would be going there.
But then that also may be a different question if you live nearby!!
Quote/ copy and paste:
Code of Maryland Regulations (COMAR) govern the transport of hazardous materials across our toll facilities. Under these regulations, vehicles carrying bottled propane gas in excess of 10 pounds per container (maximum of 10 containers), bulk gasoline, explosives, significant amounts of radioactive materials, and other hazardous materials are prohibited from using the Fort McHenry Tunnel (I-95) or the Baltimore Harbor Tunnel (I-895). The Francis Scott Key Bridge (I-695, the Baltimore Beltway) is a convenient alternative route for crossing Baltimore's Harbor.

[NeilV]

Originally Posted by Mongobird

There are tunnels and some bridges where propane is restricted. Normally, it just needs to be shut off, but in a few cases it is not permitted and it is easiest to simply have empty tanks.

A good metro example is Baltimore.

I just go around the Baltimore tunnel. Its less bother than having to fully purge the propane tank and then have to refill it afterwards. The Baltimore tunnel only has lanes to accommodate vehicles up to 8 feet wide so an 8.5 foot wide Meridian really doesn't belong in there anyways. Yes you may be able to squeeze through without getting bothered unless you are involved in a traffic mishap or some other violation but...

Anyways over the past 50+ years of RVing, We've just planned around the tunnels that require more than just pulling over to turn the propane valve off and don't go through any special gyrations to purge the propane tanks, etc. Its usually going to take more time and cost more to purge and refill the tank rather than just go around.

My wife after seeing the Stallone Movie Daylight really does not like tunnels that go under water anyways.

[nownzen]

I have that fridge and it draws 5 amps. The eyebrow board and control board run on 12v to get the fridge running. I haven't seen too many that offer 12v operation. Your fridge should automatically start running on propane once you unplug. Also, haven't seen many places where propane is not allowed. Where are you going to??

[dickb46]

We have a 2003 Journey with a 1200 refer.
Camping World replaced it when we bought it and plugged it in wrong. (the refer was plugged into the outlet for the ice maker and the ice maker wasn't plugged in.. who knows, dopes)
At any rate the outlet lower left (from the out side access) is fed by the inverter, the other, (where ever it is) probably isn't.
We can run the refer on the inverter. We did it twice. Both times the hotel batteries were low when we reached our destination so we don't do that any more. (2000 wat inverter, 160 amp generator on the CAT)

[Mongobird]

Originally Posted by dickb46

We have a 2003 Journey with a 1200 refer.
Camping World replaced it when we bought it and plugged it in wrong. (the refer was plugged into the outlet for the ice maker and the ice maker wasn't plugged in.. who knows, dopes)
At any rate the outlet lower left (from the out side access) is fed by the inverter, the other, (where ever it is) probably isn't.
We can run the refer on the inverter. We did it twice. Both times the hotel batteries were low when we reached our destination so we don't do that any more. (2000 wat inverter, 160 amp generator on the CAT)

Good data point.

Your experience makes some sense, given that the peak draw on the inverter when cooling will be about 50 amps. 160 amp alternator on the c7 engine is not really a charger, it is just a power supply. So pulling down the output voltage even a volt with the refrigerator operation, could result unless charge to both the house batteries and the chassis batteries. In my case the house batteries are AGM, and the chassis batteries are flooded. So as it is the charging from the alternator power supply it's not symmetric between the two of them, and it is not ideal for the AGM batteries.

I suppose the best solution for the batteries would be to have a charger for each type of battery. That way the house batteries get charged with an AGM profile, targeting AGM voltages, and the chassis batteries get charged with a flooded profile.

I do have a question which is slightly off topic, but relevant. Natural gas regulators for residences, and it may actually be before the regulator, have a flow limiter. The flow limiter toggles with higher flow rates shutting off the natural gas flow. Is there a similar flow limiter in the propane system on the RV?

I will look into this today.

My motivation for using vehicle power to power the refrigerator is twofold. There are some tunnels that I will frequent visiting some of my children.I have not gotten to the bottom of exactly what the regulations are in each state, and while some tunnels prohibit a certain volume of propane being carried most seem to simply want the propane turned off at the tank prior to utilizing the tunnel. The second motivation is the general discomfort that I have with having a burning flame in the refrigerator with the possibility of having a breach of the gas distribution system. I recognize that there's not a lot of black pipe running through the RV, and it's not in a spot that frequently takes hits in an accident. But I perceive it as a non-zero risk.

A use case for the RV is longer drives followed by stops. And in the case of longer drives, particularly at interstate speeds, it would intuitively seem that there would be the potential of excess electrical power available to run a modest refrigerator.

Finally I understand that's not the way things are done, but I am trying to understand what the issues are, what the risks are, and what potential solutions exist.