Fridge cold when towing?

[Jann Todd]

Originally Posted by Raspy

You would just have to keep up with the DC fridge power needs. Solar can do that, but if the cooler is in the truck, where are the collectors gonna be? Could you switch the old cooler for the new DC fridge?

I am so done with propane fridges. We just got a new Imperial X22 trailer and it has a 10 cu ft (!) DC fridge. I noticed it running a lot and checked the temp. Minus 15 degrees F in the ice section and everything frozen in the main section! Turned it to warmer and now it runs about 30-40% of the time with normal use, and about 6-10 degrees F in the freezer. 11 amps when running, so about 4-5 amps average. No huge vents on the outside of the trailer, no propane use, no temperamental behavior, no possible fire hazard. Works just like the fridge at home.

DC is fine if you don't boondock without solar. With no solar you can't keep it cold. We do just fine with propane. If we used the trailer a lot we'd look into solar maybe but after 45 years of propane fridges I think I'll stay uncomplicated since we have no knowledge of solar. Plus we like to park in the shade so solar wouldn't work well. If we had portable solar units then we'd have to be concerned about theft plus it wouldn't work while we were traveling. Not having the fridge on for 10 hours while traveling means food ruined and a hot fridge. With the cool down time then you'd be talking about 18 hours of a warm fridge. It takes about 6 hours to cool one down at least.

[ThomasC]

Raspy: Thanks for the info on your frig.

[CarlD]

Originally Posted by Jann Todd

DC is fine if you don't boondock without solar. With no solar you can't keep it cold. We do just fine with propane. If we used the trailer a lot we'd look into solar maybe but after 45 years of propane fridges I think I'll stay uncomplicated since we have no knowledge of solar. Plus we like to park in the shade so solar wouldn't work well. If we had portable solar units then we'd have to be concerned about theft plus it wouldn't work while we were traveling. Not having the fridge on for 10 hours while traveling means food ruined and a hot fridge. With the cool down time then you'd be talking about 18 hours of a warm fridge. It takes about 6 hours to cool one down at least.

If you have something that serves you well it doesn't make any sense to change. I built my trailer from an empty shell so I went with newer technology. I have a compressor fridge and LFP battery which work fine for boondocking relying on solar to charge the battery. While traveling it uses the TV alternator thru a 9 amp victron DC-DC isolator. We spent 80 days on our trip to Alaska in 2019 and never plugged in. Also the compressor fridge cools down in less than an hour when we turn it on.

Compressor fridges have different characteristics than propane fridges. One thing I don't like about the compressor fridge is that the waste heat is vented into the living space, nice in the cooler seasons but not in the summer. Unfortunately in cooler seasons the fridge does not run as much so it doesn't produce as much waste heat but it also uses less power which is good because there is less sun to recharge the battery. These are just some of the characteristics. End of Ramble!

On a side note: I have a Servel propane fridge in my camp that has to be pushing 80-90 years old and it works fine, even the gaskets are still in pretty good shape. It just requires a little cleaning once in a while.

[Raspy]

There is more to solar than just running the fridge, but that is an excellent use for it. And a compressor fridge works like your home fridge. When you turn it on, it gets cold right away, and will get very cold if turned down too far. With solar, no generator needed, camp indefinitely with no propane use for the fridge and no re-charging of the batteries by running the tow vehicle or generator. It is a silent and reliable power source that keeps the batteries charged and healthy, so you can have power for other things, like charging phones, computers, watching movies, running a microwave to re-heat, or running the heater, which takes a lot of DC power. A small benefit is if you do not have insulation in the roof, the collectors keep the sun off a good percentage of the roof.

Before I had solar, and when boondocking, I had only a couple of days before I had to charge the batteries. Now, there is no reason to ever hook up to another power source and we can stay out as long as we want to. It is very satisfying to see the batteries climbing in percent of charge without doing anything.

Absorption refrigeration was a marvelous invention. Extremely creative. It brought refrigeration to areas with no electricity, and it has served the RV community reasonably well for a long time. But how many of you would get rid of your compressor fridge at home and install an absorption one instead? They just do not compare well in real world use. And now, compressor fridges are practical in RVs. They work better than the propane ones. They run from the sun! They bring all the convenience of a home fridge to your trailer.

As Carl mentioned, they expel their waste heat into the room, and they are little bit louder than a propane fridge. It sounds like a muffin fan running.

[parmm]

Originally Posted by Raspy

As Carl mentioned, they expel their waste heat into the room, and they are little bit louder than a propane fridge. It sounds like a muffin fan running.

But couldn't it be mounted similar to a propane fridge where the rear of the fridge is framed off from the inside and the coils are vented to the outside? Seems like that would be possible.

[Raspy]

Originally Posted by parmm

But couldn't it be mounted similar to a propane fridge where the rear of the fridge is framed off from the inside and the coils are vented to the outside? Seems like that would be possible.

That seems perfectly reasonable to me. And with a conversion to compressor from absorption, there are already outside vents available. In fact, way more than is needed.

[gordon2]

A typical roof RV air conditioner is 13,500 BTU / hour.
A typical 1500 watt electric heater is 5115 BTU / hour.
A Secop (Danfoss) compressor type fridge is 118-272 BTU / hour (total expelled heat).

So you can vent it if you like, but it won't make a big difference... and in colder weather you will be venting a small amount of heat that you might want to keep.

Now if you are using a less efficient fridge compressor then things change a little (but not much). However the efficient Secop type is a much better option if you spend even a short time off shore power, including when traveling.

[Raspy]

Gordon,

The only problem I know of with venting a compressor fridge is that it must be vented. Either into the room or outside, but not into a closed cabinet.

I agree that the amount of heat is minimal. Venting into the room also vents the low noise into the room, but again, that is minimal.

I think that over time, the obvious benefits of these new fridges will convert even the most stubborn folks that think a propane fridge is the only reasonable system. There may be times when it is not the best, but in the vast majority of examples, I think it is.

The remarkable efficiency and ease of installation of solar, as well as the new fridges, make it a no brainer for me. Free fuel from the sun, arriving silently, that can also be used for other purposes, is just marvelous. I no longer have any interest in shore power or a generator. Propane is only for cooking and hot water. And I can watch the battery state of charge climb whenever the sun is out. Excellent.

[MyronL]

Well, pardon the interruption but, since this is the first I've heard of a Black Series HQ19 trailer, I am curious. Is it a stickie or is it fiberglass? How do you like it?

[Raspy]

Originally Posted by MyronL

Well, pardon the interruption but, since this is the first I've heard of a Black Series HQ19 trailer, I am curious. Is it a stickie or is it fiberglass? How do you like it?

The HQ19 is an Australian style caravan. Aluminum skeleton with heavy aluminum skin. Independent suspension and a luxurious interior. I had it for a year and a half. Now I have an Explore X22 off-road trailer with perimeter frame, torsion independent suspension, 12" hydraulically adjustable ride height and Crane Noble fiberglass panels over an aluminum skeleton. Seriously insulated with no pipes underneath and rated for use down to 40 below. The X22 has 480 AH of lithium, 650 watts of solar, a compressor fridge and a separating toilet with no black tank. The pee is piped to the gray tank. I like the X22 more than the HQ19.

Here is a picture of the HQ19 as I started up the stair steps at Seven Mile Ridge in Moab, and a couple of pics of the X22 near Diana's punchbowl in Nevada.

[RogerDat]

One thing to consider is cost of electric vs propane.

My battery bank is (4) 120 AH lithiums for 480 AH.

That is a significant cost and replacement cost. Solar panel requirements are increased. While many run on a single panel without an issue having that sort of load increases how many watts of panel one has to purchase.

I had a 12 volt compressor fridge in an pervious camper. Pre solar being affordable. It meant I had to be very aware of my power consumption vs recharging. I used a generator and 3 flooded batteries back then. Solar can provide the power but one has to consider some bad weather for a couple or three days as a possibility.

I find is my propane filled an easy answer to determine. Can run for a long time on a single tank of propane, even longer if I have two tanks.

All types of refrigerators move heat from inside to outside. If the heat isn't vented it is inside. Propane has some added heat from the tiny burner but even a compressor fridge will put off heat from the back that needs to be either vented or it warms the interior.

I used blue ice packs in freezer that froze when running and then helped maintain cooler temps when fridge was not running. But those were refrigerators where the freezer was aluminum box that chilled the whole interior so packing that with frozen food and blue ice packs kept the entire fridge cold all day while driving.

I'm a fan of the propane because it runs so long on a little propane which I already have. Over 4 batteries and a second solar panel that I don't have and would need to purchase in addition to the replacement refrigerator.

As I recall the 12 volt coolers can only get about 45 degrees F below ambient temperature. If that is still the case I'm not sure they could freeze anything. Unless temps were in the 70's where cooler was running.

[hannahzaharik]

Originally Posted by Jann Todd

We drive with the fridge on propane. If it was so dangerous they wouldn't make it so you could do that. There are safety devices on propane tanks. Most RV'ers run with propane on. Just shut off all appliances before entering gas pump areas. Spark igniters do just that. Ignite. Gas fumes ignite. I've seen several RV's and trailers wreck and never have seen one burn because of the fridge being on yet. I know it happens but I've seen more cars and trucks burn from fuel problems, hot tires, etc. than RV's from refrigerators being on and there's almost as many RV's on the roads as cars these days. Our 12V runs down our battery while driving so we don't use the 12V except for trips to the gas stations from a campground. After fueling we pull out and put it on propane.

How do you keep your propane lite while driving? I tried it for the first time the other day and when we got to our destination (1 hour away) it was blown out

[Lynn Eberhardt]

Some stay lit, some don't. Mine doesn't. Chech this entire thread for ideas.

[Jann Todd]

Originally Posted by hannahzaharik

How do you keep your propane lite while driving? I tried it for the first time the other day and when we got to our destination (1 hour away) it was blown out

Make sure your pilot is clean and set good. We just came through NM in horrible wind and ours stayed lit. We had to stop because of visibility and 50mph wind gusts. Fortunately we got off the road just as they hit. We keep it clean and have never had a problem with it. Maybe have your propane pressure checked to make sure it is right. The temps have been in the 80's-95 and our fridge has stayed at 34 or below. We keep an indoor/outdoor thermometer in it and don't need to open it to see if it is cold. We have it on the highest setting #5. We had a 1971 camper that wouldn't stay lit and put a furnace filter in it when driving to help stop the wind. That did it some but then you have to remove it if the temps are hot and you are parked.

[Paul O.]

We also had the problem with the pilot flame being blown out while driving, especially on windy days. I have found a piece of closed cell foam material, about 3/8 inch thick and it covers about half of the lower opening (the forward half). It is much better, but we do check it out every time we stop for gas or lunch. Because it covers only about one half, I leave it there even on hot days.
On edit: we check it by opening the cover and touching the tube that has the heating elements in it.

[Markz]

We run our refrigerator on 12v while towing.

We have a CTek dc to dc converter that sends power from my alternator to my trailer batteries. I ran the 12v refrigerator power to a relay switched by my trailers running lights (this way I can control power to the fridge from my dash). This prevents the tow battery from being run down when parked and the relay is connected to my trailer's on-board batteries allowing those batteries to be used for the 12v if parked for an extended time.

We also installed a switch in the camper allowing us to turn on the camper's running lights, thus triggering the relay to run the refrigerator 12v power.

We only use the LP to run the refrigerator when boondocking.

When camping with hook-ups, we run the refrigerator on 110v AC.

I do pre-cool the fridge with 110v AC prior to trips, but while traveling the 12v does well to keep the fridge cold.

[WDavidG]

Originally Posted by Markz

We run our refrigerator on 12v while towing.

We have a CTek dc to dc converter that sends power from my alternator to my trailer batteries. I ran the 12v refrigerator power to a relay switched by my trailers running lights (this way I can control power to the fridge from my dash). This prevents the tow battery from being run down when parked and the relay is connected to my trailer's on-board batteries allowing those batteries to be used for the 12v if parked for an extended time.

We also installed a switch in the camper allowing us to turn on the camper's running light, thus triggering the relay to run the refrigerator 12v power.
.

We have a similar DC set-up to this one described by Mark. The only issue we have is that it works almost too well -- on long trips we have to periodically turn off the fridge for an hour or so to prevent food from freezing. Our dc-dc converter is in the trailer with its own dedicated 6 gauge wire from the alternator. The 12v source via the 7 pin would be insufficient for this to work.

[Steve Carlson]

I run mine on propane when traveling, works fine. Doesn't seem to use much propane, either.