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Fridge advice and guidance.

eXodus said:
you still need to vent a compressor fridge if you do not want the A/C have to expel the heat as well.
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I remember either dometic or norcold manuals has the temp differencial that they're rated for and I believe it's like 35ish degrees.

I've never seen a residential fridge externally vented before. It's a refrigerant based system vs ammonia and the heat expelled is not much at all and I haven't been able to capture on flir
 
Rocketman said:
In 2019 on a trip back from Alaska, my parents 4 year old NeverCold leaked all the ammonia. My dad got the Amish replacement but decided to stay with propane. We put it in- was not a hard job - but 2 people needed.

When we went full-time I didn’t want our 22 year old NeverCold dying at a bad time - and it wasn’t working super well - old doors, seals, etc.

We went with a Residential. Because of unique size in the MotorHome we went with a Fisher & Paykel counter depth model (no ice maker). It was a little taller and narrower. (Had to move the furnace down to move the fridge floor down- but it all fit!

We leave our Multiplus inverter on 24/7 so that wasn’t a factor. I added another 400w of solar and that about covers the fridge use (unless it’s cloudy- then it’s generator time).

The residential fridge gave a LOT more room inside for food. Also it keeps the fridge temp very stable - (the NeverCold fridge temp wandered during the day), and the freezer is actually cold - ice cream is perfect!

It has worked perfectly for 2+ years so far…

I would NOT NEVER EVER go back to an absorbing fridge - and neither would my wife.
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When I bought my 1st rv it was almost 20 years old and I put a temp sensor in the fridge and couldn't get the temps stable. Everyday 10+ degrees. Replaced temp sensors, bought all the extras like a fan inside and special temp, same issue. Built an extra fan system for intake and exhaust vents outside, same issue.

Swapped with fridge above and temp swings are max 5 degrees, and thats with the temp sensor at top by door. Also get a power outage alarm and high temp alarm.
 
Oh yea, as part of the residential install - sealed up and insulated (the best I could), the old fridge roof vent and side vent.
 
RoadTurtle said:
My Norcold has turned into a Nevercold :(
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I'm looking primarily at the conversion kit to add a compressor kit to my existing fridge. Second choice may be replacing the whole fridge with a RV specific 12v compressor fridge. Third choice might be a residential fridge. I'm leaning to 12v over 120v, but shouldn't be an issue managing either one.

Several questions, with the conversion kit, how good are they at holding temps? What is their typical 24 hr run time?

What changes have members of the tribe made, and why did you go with that type?
Not terribly worried about capacity, 600ah battery, 1200w solar.
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We quit using the 3 way fridge in the truck camper 2 years ago. It worked like any 3 way and nothing wrong with it. We didn't need it as we have a Dometic CFX95 in place of the rear seat of the truck cab. I run a quick connect off the camper to a hardwired system on the truck so the fridge runs off solar. This works very well, but if it's raining or you want to get some food from the fridge in the morning for breakfast, you have to go outside to the truck cab.

I looked into swapping out the 3 way for a 12/24V compressor fridge so for some things we could have it inside the camper. Lately I'm thinking it actually would be a better idea to use a chest type compressor fridge/freezer similar to the CFX95 but smaller and mount it on heavy drawer slides. Many of the van people have been doing it this way. One advantage over the door type is you don't lose cold air when opening a chest type.
 
justinm001 said:
I remember either dometic or norcold manuals has the temp differencial that they're rated for and I believe it's like 35ish degrees.

I've never seen a residential fridge externally vented before. It's a refrigerant based system vs ammonia and the heat expelled is not much at all and I haven't been able to capture on flir
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pretty simple math.

My 10 cubic 120V fridge at home needs about 1.5 kWh electric / day, Most fridges have about a COP of 2-3. So those are then 3-4.5kWh of heat generated.
Those are 3 kWh of heat you need to move through the A/C requiring you another 1-2kWh to get rid of it.

Sure if your main scenario is - heating - then a interior vented fridge is awesome - it's additional "free" heat. But if you are mostly cooling - it's terrible.

The 12V RV fridges - for example Dometic are designed as drop in replacement for Absoprtion and are venting to the back into the old cavity - so "external"
 
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eXodus said:
pretty simple math.

My 10 cubic 120V fridge at home needs about 1.5 kWh electric / day, Most fridges have about a COP of 2-3. So those are then 3-4.5kWh of heat generated.
Those are 3 kWh of heat you need to move through the A/C requiring you another 1-2kWh to get rid of it.

Sure if your main scenario is - heating - then a interior vented fridge is awesome - it's additional "free" heat. But if you are mostly cooling - it's terrible.

The 12V RV fridges - for example Dometic are designed as drop in replacement for Absoprtion and are venting to the back into the old cavity - so "external"
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Idk about all that. My daily average of my 19cuft fridge is .35kwh. Idk how efficient it is but I can't find any heat source with a flir.

I also don't think it works like that as any cold air that escapes from the fridge goes into the rv offsetting the temp.

I'd think Absorption fridges introduce much more heat than electric into the rv because insulation only helps so much and it literally uses heat to suck cold air out
 
I replaced a 6.5’ Dometic propane with a 9.2’ compressor Nova Kool in the same opening. My energy usage went down!
 
eXodus said:
My Dometic Absorption fridge- properly installed - NOT in a slide out - with side vent in and roof out - is perfectly silent and works in 100F humid heat in Florida and keeps everything frozen at decent constant temperatures. It has some trouble cooling things down when you freshly load it. But as soon as it hits the setpoint it stays there for weeks. It is not swinging more then my regular cheap 120V house switch.
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Mine worked well also until it didn’t.

Had a Keystone 5th wheel and 2 years into having it the fridge coils for whatever reason leaked out.

Replaced with big box fridge because it wasn’t under warranty and replacement was $1500 vs $200.

The problem with that RV was every single time you got in it something was broke and it was usually when you were 50 miles into BFE.

The very first trip we made in it to Pigeon forge the Propane valve that controls which tank is active decided no gas could pass through it no matter what tank we used.

Yea it’s still under warranty if you can find someone that does Keystone warranty then you have to drag it to their shop and wait.

Luckily I went to a big box store and found appropriate piping to at least make it work or we would have had no heat.

Combine that with an hour+ setup / takedown after dragging it through every kiss your butt turn and traffic ,then trying to negotiate parking in a slot with 60ft of truck and RV with trees ,kids, parked cars, assholes staring at you daring you to hit their lawn chair, the leaks, $70 nightly pad charges we just sold it.

Maybe if you were boon-docking it would be worth it.
 
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Nobodybusiness said:
Had a Keystone 5th wheel and 2 years into having it the fridge coils for whatever reason leaked out.
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Quality of RVs is unfortunately a race to the bottom for the last couple of years.

My 20 year old Dometic absorption fridge works perfect. Everything original. I know people in the classic RV circles which have 40-50 year old units which still work.

If my trusty old propane fridge should ever brake, I would likely put in a compressor fridge, I am upgrading solar in the moment and it's getting harder to impossible to find good quality absorption units
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Nobodybusiness said:
Maybe if you were boon-docking it would be worth it.
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That is my preferred way of camping. 80% of our trips are without hookups.
Nobodybusiness said:
Combine that with an hour+ setup / takedown after dragging it through every kiss your butt turn and traffic ,then trying to negotiate parking in a slot with 60ft of truck and RV with trees ,kids, parked cars, assholes staring at you daring you to hit their lawn chair, the leaks, $70 nightly pad charges we just sold it.
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One of the reasons we have 24FT Class A.
Setup time is literarily putting it in Park. About a second. Fits in many parkingspots, many boondocking sites are free or very little cost.

richard cabesa said:
I replaced a 6.5’ Dometic propane with a 9.2’ compressor Nova Kool in the same opening. My energy usage went down!
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Are you referring to 12V energy usage or 120V? 120V would be clear- absorption fridges when run with electric are power hungry. Would be interested in your 12V numbers and how you measured them.
 
eXodus said:
Are you referring to 12V energy usage or 120V? 120V would be clear- absorption fridges when run with electric are power hungry. Would be interested in your 12V numbers and how you measured them.
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12V.
The Dometic used 13 watts continuously to keep its brain alive. The Nova Kool uses 46 watts when running but at about 40% duty cycle that’s about 19 watts/hour. That’s up not down right?


But that’s not all, my RV had an electronic control valve to keep the propane on that used 24 watts continuously
it was close to 75 Ah a day to run a gas fridge..

So I guess I’m cheating when I say the fridge made my usage go down, there was more to it.

Now I’m around 40-45.Ah per day

And, I replaced that stupid valve with a manual one
 
richard cabesa said:
But that’s not all, my RV had an electronic control valve to keep the propane on that used 24 watts continuously
it was close to 75 Ah a day to run a gas fridge..
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that is a ton of power for a valve. The valve for the burner on the fridge needs 0.3A ~ 4W

richard cabesa said:
And, I replaced that stupid valve with a manual one
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mine came with a manual one.
richard cabesa said:
The Dometic used 13 watts continuously to keep its brain alive.
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mine uses about 0.4-0.5A with the burner off and 0.8A when the burner is on and cooling. The LEDs inside need the most power when I am starring at the food and can not decide. ;)

It disappears in all the noise of the other standby draws in my RV. (USB-Chargers, Water Heater electronics, Smoke, CO2 / Propane detectors etc.)
 
As an experiment, I've started turning off the fridge every morning for an hour. Fridge is working fine for now.
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I'm still thinking I will modify/replace the fridge after we get back home.
 
RoadTurtle said:
My Norcold has turned into a Nevercold :(
.
I'm looking primarily at the conversion kit to add a compressor kit to my existing fridge. Second choice may be replacing the whole fridge with a RV specific 12v compressor fridge. Third choice might be a residential fridge. I'm leaning to 12v over 120v, but shouldn't be an issue managing either one.

Several questions, with the conversion kit, how good are they at holding temps? What is their typical 24 hr run time?

What changes have members of the tribe made, and why did you go with that type?
Not terribly worried about capacity, 600ah battery, 1200w solar.
Click to expand...
Living in a bus 24/7 in Queensland Australia, we tried the "built for motorhomes/boats in hot climate 12v fridge." Lasted not long, couldn't keep up with 40⁰c temps.

Changed to normal residential 240V fridge freezer 5 yrs ago. Still going strong.

I wouldn't hesitate, go the way I did.
 
I understand that a few here detest Samsung but 10 years ago I replaced our 175l 3-way with a 230V Domestic 255l (9 cu ft) Samsung Digital Inverter fridge/freezer.
It is powered by a dedicated US$60 300W 230AC PSW inverter mounted behind the fridge.
Both the fridge and inverter running 24/7 have now survived the rattle and shaking of 10 years full-time travel without a single issue.
No manual defrosting was an added bonus.

For anyone interested the original 3-way devoured a 9kg (20lb) LPG bottle every 10 days.
Here in NZ that equates to almost US$7000 savings so far. Enough to replace our entire now 10 year old solar, LiFePO4 battery, fridge etc. setup - twice!

A 6 month data log from day one showed the average energy draw including inverter losses from our 4 cell battery was almost exactly 800Wh daily or in amps 2.52

The 2 large Dometic external vent hatches were removed and covered with 3mm white polycarbonate sheeting.
 
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justinm001 said:
Absorption fridges... Average consumption is .22kWh/day this week and .34kWh/day for past 30 days. Currently using only 1.5 watts! Past 30 day total consumption is 10kWh.
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umm, Im curious about the math... 0.34kwh/day means how much? You did decimals then use "k" to move decimals and now Im lost.
 
Are there no upright 12v DC fridges that will be similar price? The upright do take up less room than the chest sty bc the door opens into the walking space, not into the cabinet space.
I have a DC chest fridge and will never go back to propane. I put 1.75 inch thick styrofoam insulation around the base and sides (and keep towel on the door) so it is super insulated and runs a fraction of the time, and this makes it really quiet too. Low amp draw as opposed to the cheap dorm fridges too. I have a dedicated battery to it so know exactly how much power it needs, not a lot, and solar on sunny days, it never gets close to needing much battery.
 
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