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Looking at new 5th wheel.  we want a fridge that is gas and electric. Sales is trying to talk us into a residental fridge (electric only).  he wants to install 2  400 watt panels and a 1500 watt inverter. Claims with 5 hrs of sunlight daily that it will run my fridge 24/7.  

WILL IT  ??    any opinions or teck advise would be really helpful....

Thanks    Xglassman going fulltime.

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Possibly. A lot depends on the fridge, solar components, battery bank, your camping style and how much direct sunlight you can expect in the areas you plan to frequent.

Generally speaking... if you spend the majority of your time in CG's with shore power and only need to rely on your solar/inverter system from time to time it's very doable. For those that dry camp the majority of the time... it's still doable, but there are factors that need to be carefully considered.

I WILL say though... going with a dealer installation is about the worst way to go. You'll likely pay out the nose (2-4 times more) and the install would, highly likely, be very questionable. I've yet to see a dealer installed system that really performed up to expectations.

My "free" advice? Decide between gas/electric vs. residential based on your camping style needs alone. If solar is something you want, it woud be in your best interest to do a bit of research to really understand what your needs really are and what is reasonable to expect from a solar system. 

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I would not have a gas refrigerator without a fire suppression system. Are they including that with the Gas/Electric?

A small pure sine wave inverter (sized for the fridge) and batteries can run the fridge for quite a while when moving. If you don't open the fridge it stays cold for a while too. It's all about how you are using and what you want.

 

Rod

 

White 2000/2010Volvo VNL 770 with 7' Drom box with opposing doors,  JOST slider hitch. 600 HP Cummins Signature 18 Speed three pedal auto shift.

1999 Isuzu VehiCross retired to a sticks and bricks garage. Brought out of storage the summer of 2022

2022 Jeep Wrangler Sport S Two door hard top.

2007 Honda GL 1800

2013 Space Craft Mfg S420 Custom built Toyhauler

The Gold Volvo is still running and being emptied in July. 

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Welcome to the forums, XGLASSMAN!

 I'm not into solar so will leave the tech answers on this one to others. I do have one comment about sticking with the standard RV refrigerator. It may be a major price difference between that and the upgrade and he somehow gets a bonus for pushing the equipment he is, so be very careful. If you do choose the standard RV refrigerator, do not allow yourself to be frightened of them as I have used that type since our first self-contained RV back in 1974 with no problems, but you do need to maintain them.  If you go with the RV type, I also suggest that you add one of the ARP-RV controllers to the unit as soon after delivery as feasible. 

Good travelin !...............Kirk

Full-time 11+ years...... Now seasonal travelers.
Kirk & Pam's Great RV Adventure

            images?q=tbn:ANd9GcQqFswi_bvvojaMvanTWAI

 

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Avoid this dealer and find another.

A medium residential refrigerator will pull about 700 watts when it is running and it will be running close to full time in warm weather.

The proposed 800 watts of solar will barely keep up put only when you are in full sun.  Panels are not going to reach their rated wattage unless the sun is directly overhead.  Panels lose efficiency when the sun is at an angle, with passing clouds, on cloudy days, when panels are blocked by leaves or objects on the RV roof.  In addition, inverters are inefficient.  They lose at least 10% of the theoretical power due to heat.  In addition you will need power for other purposes.

If you go for a compressor refrigerator, you will need a much bigger solar panel array and of course you will need to be able to store power for night time use and for cloudy days.  A quick calculation will indicate the storage problem.  If you want to run a 700 watt refrigerator off of  batteries, the 12 volt amperage will be 700 divided by 12 equals  58 amps.  A good sized deep cycle battery will hold about 100 amp hours of power but you can only use about half or you will greatly shorten the battery life.  So for every hour the refrigerator runs without solar, you will deplete a fully charged battery. 

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My residential refrigerator does not run full time in the summer. They are well insulated and perform well on an inverter and batteries. I have 1000 watts of solar and 600 amps of lithium batteries. My batteries are usually charged by 10 or 11. 

Ron C.

2013 Dynamax Trilogy 3850 D3

2000 Kenworth T2000 Optimus Prime

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I did give a worst case example, but we may also have different ideas about "summer".  I often camp when day time temps reach upper 80s to low 90s.  My small 12 volt compressor refrigerator is very efficient...at least for moderate temperatures.  It will only run about one third of the time when temps are in the mid 70s but that goes to full time when temps reach the mid 80s.  I am assuming bigger units have the same performance characteristics but perhaps they are more efficient. 

BTW, what was the cost of that 600 amp hour lithium battery pack?

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Yarome & Kirk gave you very good advice. 

Some comments & thoughts:

--  Usually a residential fridge option in an RV come as a package that includes an inverter and extra batteries. 

--  I have seen RV's coming standard with a residential fridge, including batteries and inverter, then if you want the gas/elect fridge, it is an extra cost option.  Kind of the reverse of what the salesman is selling.  If memory serves me correctly it is Tiffin Motorhomes who does this.

--  Many people much prefer the residential fridge.  It does keep food and freezer colder better. 

--  You don't need the solar to keep your batteries charged for a days drive.  That is why the extra batteries are included in the package.

--  If you plan on dry camping or boondocking, don't even think about going with what the salesman is selling.  Do you research on your electrical needs are going to be and design a system you need or go to a reputable solar/inverter/battery installer. 

--  There is lots of info available by searching this forum for "solar" and/or "batteries".  Also once you have gathered some info come back and start another topic with you specific questions. 

--  There are a number of people who boondock/dry camp with residential fridges.  Ronbo who replied apparently is one of them.  It can be done, but it takes planning and research. 

--  If you like, gather all the specific info about what the salesman is wanting to sell you, post it in a reply to this topic and a number of people will provide advice on the package.  We need battery size, type and mfg.  Solar panel specific size and the specs for the panels.  Brand and model name of the inverter.  Any other info you can get from the salesman.  Also include price of gas/elect fridge & the residential fridge option. 

Al & Sharon
2006 Winnebago Journey 36G 
2020 Chevy Colorado Toad
San Antonio, TX

http://downtheroadaroundthebend.blogspot.com/

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FWIW we had a residential fridge in our bus conversion. The compressor had been replaced with a high efficient 12 volt compressor. I used to bent spoons 'stealing' ice-cream all year round!!!

In reality you can choose any fridge. The trick is balancing the panels with the battery storage. Also keep in mind the huge variety of panels and battery types. There is no one answer as it will also depend on lights, fans, micro waves etc etc etc etc.

regards

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Good info from Al and Ronbo and Bruce.

I agree with Al that a residential is "out-of-the-box" better at cooling and freezing, however, I wouldn't shy away from an absorption reefer. With the addition of a third-party thermistor and fans (all told ~$60), my lp/electic keeps ice cubes rock solid and I have never had any food spoilage.

If you plan to dry camp frequently, or don't have the roof real estate for an adequate number of panels to drive a residential, IMHO, an LP reefer is still the better option. Even having the space for panels, you need to consider the cost vs. modding an absorption reefer.

Just additional points to ponder. It all comes down to a balancing act and finding the best fit for your particular style of RV'ing. There really isn't a one size fits all solution.

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A few more comments. Our compressor was a 12 volt Danforth. A high efficiency compressor is paramount. But there are many other ways you can help. Many manufacturers build the fridges into cabinet work. Fridges create heat and in those cabinets the fridge gets hotter and hotter and has to work harder. So ventilation is very very important. Our bus conversion was custom built for us. I designed it with the fridge in the center of the bus away from walls. The afternoon sun on the outside wall can be a real battery killer. If you are stuck with a fridge inside a cabinet and against a wall then do as much as possible to ventilate the cabinet. Then see how you can shade the outside wall where the fridge is located.

Keep your fridge as full as possible. Full soda, or beer, cans will hold their temperature for a long time. Air wont. Put solid shelves in the fridge so it is harder for the cold air to 'fall' out of the fridge when you open the door. I could go on and on. It's a management issue as much as a technology issue.

This is one of those situations where there is no silver bullet. It's a combination of a few degrees here and a few degrees there.

regards

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Do you expect to be living off the grid with access to LPG supplies for long periods of time.If the answer is yes you want to look at a 12 volt fridge. It should be a top opening compressor fridge.

An ARB Fridge freezer is a self contained unit that you could take with you in the car. as well as using in the RV.

But for maximum efficiency go for a top loading insulated box with at least 6 inches of insulation and a separate cooling unit.  I have a Adler / Barbour SuperColdMachine CU-200  which I am very happy with. This can be run off 12 volt batteries without the inefficiency of an inverter. 

Otherwise go for a RV gas/110v fridge unit and run it off gas when you don't have lecky.

Your salesman does not understand the relative efficiency of different systems.Running a domestic fridge off an inverter is about the most inefficient way to go.  

FT since September 2007

Safari Trek + M/C

http://johncarolandcharro.blogspot.com/

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