Residential fridge - cooling while under way

[wanderso]

I read with interest about new rigs with residential fridges installed and retrofits being added into used RVs. How are you keeping it cold when under way, especially if doing a 12 hour drive on a hot summer day? True, a few hours are ok with no power as long as you keep the door closed - just like having a power outage at home. Seems though that it would push the limits of most inverters and the rig's alternator to start the compressor when on the road. (?)

Also, many fridges require air space around the fridge itself to cool properly. How are you solving that?

Thoughts? I'm mainly curious as I may do it at some point in my Class C. (don't expect to boondock - always have access to shore power; don't want to run the generator for hours while on the highway).

[paz]

All the RVs that I am aware of that come from the factory with a residential refrigerator have 2 extra batteries in the battery bank and the refrigerator is run by the inverter when the RV does not have 120V power available. The vehicle alternator keeps the batteries charged when on the road. The extra batteries allow the fridge to run all night on the inverter when boondocking.

We added a residential refrigerator (Samsung RF197) a few months ago. Because we only have 2 house batteries in our gasser, we can't boondock anymore because of the new refrigerator, but the motorhome's alternator has no problem keeping the batteries charged so we can run the refrigerator on the inverter when we're on the road.

I have read about problems some people have had getting other brands of refrigerators to start on a 1000 watt inverter, but the Samsung starts and runs fine on our 1000 watt Tripp-Lite inverter. I even tested it while parked with the TV and satellite receiver running at the same time. The Samsung will also run on a MSW inverter while most other brands require pure sine wave.

Some people who have added a residential refrigerator say they are fine driving 4 or 5 hours without power as long as they keep the refrigerator door closed. If they have a longer drive, they start the generator when they stop for lunch and run it for a while. There is no need to run the generator constantly, just a short time to allow the fridge to cool off again.

The wood face frame around our new refrigerator has a space of about 3/8" on each side and above. The space around the refrigerator behind the frame is about 2" wider on the sides and on top.

[Luckiest Dreamer]

Winnebago sells the double door frig as an option on some models and standard on others. With mine it came with a bit larger inverter. (2800W instead of 2000W)There is no problem keeping it cold with the right sized inverter. My MH also comes equipped with a trickle solar charger that charges the batteries as needed. The inverter recharges the batteries when ever it is connected to shore power , and I believe whenever the generator is running. With the right equipment installed it does this automatically. I can even turn a switch and the generator will start on its own should the need arrise!
No, I cannot tell you how it is done. All I know is that it works well going down the road and if I should have a problem, I ask the DW if she remembers what the manual said about it!

[wanderso]

Thanks. This answers several questions. In my case, I'm also limited to 2 batteries unless I want to add a cable run to an adjacent storage compartment several feet away. I only have one today. (class c) I guess I still worry a bit about the pressure on the alternator, although that concern may be unfounded. For mounting, how and where did you secure the fridge via bracketing? Did you leave the propane fridge's roof and side vent in place for added venting? Low voltage events can cause real harm on electric motors, especially at startup. Sounds like your inverter manages the power spike/need better than most. Example of the impact of low voltage on electric motors: http://ecmweb.com/mag/electric_save_motors_during/

Some residential compressors have a "knocking" noise when they are shaken/moved. Noticed any noise when under way?

[wanderso]

In my case, this seems like the fridge that would replace my Dometic is the . ETOMSRXTQ (Whirlpool). $339 at Sears. Main gripe appears to be with the placement of the light (top center of shelf). 9.6 cubic feet.

Dimensions
Depth Radius 48 3/8
Depth 26 7/8
Height To Top Of Cabinet 59 7/8
Width 24
Depth Closed Including Handles 26 7/8
Height 60 3/8

[Ernie Ekberg]

On a hot summer day, I run my 12,500 watt generator to run my 3 air conditioners and whatever else we need

[docj]

We have a Samsung RF197 with 4 golf cart batteries. In order to avoid the starting voltage issue you raised, Samsung states that its refrigerator can have a max current draw of ~11A and that inverters should be sized with this in mind. We have a 2.5kW Xantrex MSW inverter which seems quite adequate for the fridge.

With respect to the roof and wall vents, ours were sealed and foamed to provide extra insulation. We did not want the back of the fridge exposed to ambient temperatures because the ice make water line runs back there. The fridge is held in place with one angle bracket on the top secured through the roof vent opening and two angle brackets at the bottom front. We have approximately 1" clearance on sides and top for venting purposes.

It should be noted that a reliable individual on another forum has posted that the RF197 is not currently available which would be a shame. It is a counter depth model that doesn't intrude any further into the coach than does the Norcold 1200 it replaced. The only Samsung alternative may be a standard depth model which would intrude an extra couple of inches.

[paz]

Originally Posted by wanderso

For mounting, how and where did you secure the fridge via bracketing?

Fridge is bolted to the floor in the back with lag screws that pass through existing holes in the metal pan on the bottom of the fridge. It is also bolted to brackets in front using the threaded holes where the leveling legs were screwed in. There are also foam braces in several locations around the top to keep the top from swaying.

Originally Posted by wanderso

Did you leave the propane fridge's roof and side vent in place for added venting?

No, I closed all vents. The RV refrigerators are sealed around the face and must be open in back to vent combustion gasses and to cool the coils. Residential refrigerators aren't typically vented to the outside and are cooled by room air. I didn't want cold or hot outside air getting inside, so I sealed the vents.

Originally Posted by wanderso

Low voltage events can cause real harm on electric motors, especially at startup. Sounds like your inverter manages the power spike/need better than most. Example of the impact of low voltage on electric motors: How to Save Your Motors During a Brownout

Most inverters will handle a spike in current of up to 2 times their rating. Our 1000 watt inverter will handle 1800 watts for a short period. I have also heard the 11 amp peak that docj mentions. This is only about 1300 watts at 120V.

Originally Posted by wanderso

Some residential compressors have a "knocking" noise when they are shaken/moved. Noticed any noise when under way?

No noise form the compressor. Someone posted on another forum that Samsung said there was no problem with the compressor running while the fridge was moving.

[paz]

Originally Posted by docj

...It should be noted that a reliable individual on another forum has posted that the RF197 is not currently available which would be a shame. It is a counter depth model that doesn't intrude any further into the coach than does the Norcold 1200 it replaced. The only Samsung alternative may be a standard depth model which would intrude an extra couple of inches.

You might be right that it is no longer available. I don't see it on Lowe's web site anymore. That is too bad.

Another advantage to the counter depth model is it will fit through some RV doors so you don't have to remove a window to get it in.

Looks like we just got ours in time. We love having hard ice cream, and it makes ice faster than we can use it.

[hooverbill]

The new AC coaches that are all electric come with eight 6 volt batteries and two 2,000 watt Pure Sine Wave inverters.

I think the jury is still out on how residential refers will hold up getting banged around on the road in an RV.

[Iron Man]

We have a GE residential fridge in our 07 Essex and love it. We have about 55,000 miles on the coach with no fridge problems.

[Coma]

Originally Posted by hooverbill

I think the jury is still out on how residential refers will hold up getting banged around on the road in an RV.

You may be right, although I can't imagine they could be worse than the 1200lrim it replaced.