I am starting to really dislike my camper solar

[hoyden]

Hey Machinebuilder - yah, that piece that 'slides' is at the top kinda silvery looking. I change it's position when the camper isn't in use and power is off. It holds the fridge door slightly open so that it can air out, but doesn't let it flop around while driving. I definitely do not have that in the open position!

I think Vic (someone else in this thread? sorry if I forgot!) also mentioned that the MPPT controller is more efficient.

 

[PaulT]

Replacing the fridge gasket should help tremendously, I saw on another thread something about a piece that slides and keeps the door from closing completely when not in use. I don’t know anything about this but it might be worth looking in to.

if the fridge is Dometic, there is a metal control top center of the fridge that either keeps the door slightly ajar for ventilation or allows the seal to completely close the door for use when cooling.

With the door open, the control moves to the left to allow venting the interior or moves to the right to allow sealing for refrigeration.

It is important to check that. Do not move the control with the door shut as that can damage the control. If that doesn'tprovide sufficient sealing, you can adjust the closure by loosening the fridge and sliding it out enough to access and adjust the control at the top of the fridge.If you are taking the camper in for service, it may be better to have the service guys make that adjustment

Paul

 

[klahanie]

I have two thermometers in the fridge, if that's what you mean?
I have had it at 6 - 6.5 for the front to not be too warm. But sometimes that's too high and the back freezes.
Like now - it's 30F in back (too cold), and 38F in front. An 8 degree difference!
It's very variable.

I put the door thermometer in the back of my fridge with the remote one and left for the day in Bill's truck.
(Mine plugged in to shore power.)
Got back to camper about 9 hours later, and remote one reads 27F and the other one @ 25F.
I didn't change the fridge temp from yesterday.
It killed my avocado. LAME

Thinking out loud here ... I wonder if a difference in bus voltage (system/distribution voltage) makes a difference to your fridge compressor efficiency such that given enough time it would account for the difference in final temp.

I'm thinking the first post quoted above was after driving much of the day (powered by alternator and house battery) vs the second post (shore power - either 110AC converted by the fridge to what ? DC voltage or the charging or float voltage from the camper charger, 13.5, 14.5?). Also a likely factor is difference in ambient air and any radiant heat, driving vs parked.

I know with our 3 way absorption type fridge the resultant cooling will be different if powered by 110V vs 12V all other things being equal. Of course there can be many variables with fridges.

Obviously I wouldn't know what model fridge you have but I'm guessing it isn't (internal) temperature controlled.

Bill is going to replace my battery separator tomorrow and I'm gonna see about replacing my fridge door seal (it's no bueno)
I'm thinking that I might hafta get another panel, tho it still confuses me why Bill - with the exact same camper as me, except that his is one year older and a roll-over sofa, same fridge and with only 100W solar is fine boondocking for (at least) a couplea days and I'm not.
Could it be as simple as my fridge door seal has been crap since almost Day 1?

Here's where the battery monitor could answer some questions esp if "Bill" has one also for comparison. Again, a systematic repeating of as many variables for each measurement would be best, testing before and after changes.

Lastly, I thought pvstoy made a good post at #123 by including duration in his power consumption data, I'm not seeing that in the other readings posted- but I could be missing it... just thinking for solar sizing.

EDIT for clarity and add quote back, ugh time stamps are gone

 

[CougarCouple]

6 degrees difference.

 

[Machinebuilder]

Ignorance on my part, but what do you mean by a controller being "80%" or "95%" efficient?

Thanks...Phil

Briefly, Power in to Power out

The PWM takes the current (amps) from the panel and puts it to the battery.

the MPPT takes the Watts (Voltage x Current) and if the panel voltage is much higher than the needed battery charging voltage will lower the voltage and increase the current. this allows more power (Watts) to go to the battery.

That's the basics, the Renogy website has a more in depth explanation.

the 15% increase is why I said the MPPT controller will help some, but in the end if you are using much more power than you are getting from the solar panel the things to do are increase the power in or reduce the power used.

I do not want to be close on the power in/power out equation if I am relying on it to keep food from spoiling. there are too many cloudy/rainy days when you don't get fully charged and have to rely on battery capacity for longer times.

 

[Advmoto18]

Below a good Pro/Con chart comparing PWM to MPPT controllers from an AU solar company.
Here is the the to the article comparing the controllers.
I think the Morningstar SunSaver MPPT is an appropriate controller for a FWC camper if using LFP for house battery.


MPPT controllers are best when your batteries are below 35% SoC. And if you are discharging any battery type, other then LFP, below 50% SoC (<12.0 - 12.2v), you are killing them and thereby greatly reducing their life span.

While MPPTs are great controllers, they are vastly more complicated to setup and properly pair with the overall solar charging system.

A Con to highlight, if installing an MPPT and LFP battery...upfront cost. MPPT controllers are more expensive. LFP batteries a vastly more expensive. However, with LFP, you have more stored energy available for use without damaging the battery, thus, we generally only need one battery in our camper.

I do not have a MPPT or LFP setup. When I ordered my system, the cost and availability of MPPT and LFP products were not as it is today. Today, I would save my coin and install a MPPT controller and a single LFP battery.

As Dawn has unfortunately experienced, these systems are not "plug-n-play". Even when installed by a FWC dealer, things can go haywire. Component specifications must be steadfastly adhered too to ensure compatibility with other system components.

I am neither a E&E or solar energy expert. However, I have assisted installing several complete systems in off-the-grid homes and in more then a handful of campers. I live near a E&E university professor who is an expert in the solar energy field. He has proved to be a valuable source of information over the years. Directly me to web sites and published documents he felt worth the time to read.

 

[CougarCouple]

Hi Dawn
Hope you and Bill are enjoying the time together. I have been thinking about the delima of not being able to re-gen but Bill with same setup does not have a problem. Sounds like this is a problem you have had since day one, you have mentioned. Let's go with the assumption that both campers are identical and the culprit for your rig is the refrigerator. It could only be how long the compressor runs or the compressor is for some reason consuming more power to run.
Can y'all isolate the power draw for the refrigerator on each rig and see what each draws? If they each draw the same or really close, then it must be/ might be run time and that would lend to the idea that the door gasket might be the culprit.
Seems like there is a lot of ideas towards maximizing re-gen of the batteries with solar, which is good but might mask the problem. Also might be that that is the problem. If it is the problem wouldn't a lot of others have the same or similar complaint.
Did you ever identify the unknown power draw you mentioned in an earlier post?

Russ

 

[Vic Harder]

Good questions and approach Russ. Maybe Dawn is opening her fridge more often to take out adult beverages to help soothe her frustration.

 

[hoyden]

Good questions and approach Russ. Maybe Dawn is opening her fridge more often to take out adult beverages to help soothe her frustration.

Hahaha!

Russ, I think you might have hit the nail on the head. Today, Bill and I went to Lowe's in search of new door seal for my fridge. I have had absolutely no luck finding actual replacement seal - called Camping World, camper repair places, Dometic... no one could help. Dometic told me it's actually in the 'truck fridge department' (or somesuch) and gave me a different number to call. I repeated the number back to the lady, said thank you and hung up. The number was bunk! LAME!

I called a "truck refrigerator" place, and he told me that this model - the CR-80 is a kind of unusual one to get utilised, and more often used is the CR-50 and the CR-65, so I probably wouldn't be able to find parts for this one. Double LAME!

We picked up some foam window sealant in the right width and height.

Cut it to fit:

It's snug and I have to make sure there's a second "click" for the fridge to be really shut. I am hoping that it'll compress down a little so that proper shutting is a little easier, but it works fine.

After a few hours, I checked the temps and moved my fridge temp from 6.5 to 5.
After dinner, I moved it from 5.5 to 4.5 and at 9:10pm temps are reading 32 in back and 37 at the door.
Of course, it's nice and cool outside, but still... I'm feeling very positive about this fix.
I'll report back tomorrow afternoon and see how it's doing.

Tonight, I was thinking that it probably has been a big problem if indeed the fridge has been having to cycle more often because of a crap door seal. It seems like it's been a confluence of things: no charging from battery and crap seal from the get-go.

We'll install the battery separator tomorrow, so I'll finally be charging while driving.

I'll hafta find someone else to install the fancy new MPPT Controller, as it's a project bigger than Bill wants to tackle.
And that's fine - he's helped a ton!
And so have y'all! Keep fingers crossed!
Hopefully, I'll feel like making a new trip report blog post soon. I'm overdue!

 

[Vic Harder]

c'mon up to Calgary and I'll install that controller for you!!! AND give you some beers to console you.

 

[hoyden]

I'd love to, Vic! Bit of a hike right now for me tho. Wish I'd done this on the first leg of this adventure. I was up in Montana and Wyoming - much closer! https://goo.gl/maps/6AqBKUPinjx

If it weren't about to be winter, I'd consider meandering back northwards and get to you in a month or two.
But that might be tricksy that time of year!

 

[hoyden]

Odd. This morning, the back one reads 42F and the door one reads 38F

 

[Happyjax]

What did the battery read? Maybe that compressor doesn't like lower voltage? You did lower the settings though if I read it right.....

 

[Wallowa]

Odd. This morning, the back one reads 42F and the door one reads 38F

Dawn,

You may have done this...put both thermometers side by side in the refrig and see if they read the same...inaccuracy in the thermometers could have chasing your tail... Four degrees may be in the +/- of the accuracy range. Plus back of refrig is on outside wall with more direct sun and less insulation than door side in the camper.

 

[PaulT]

Dawn,

You may have done this...put both thermometers side by side in the refrig and see if they read the same...inaccuracy in the thermometers could have chasing your tail... Four degrees may be in the +/- of the accuracy range. Plus back of refrig is on outside wall with more direct sun and less insulation than door side in the camper.

*2 on checking out any differences in readings between the two units located together. Good idea!

Paul

 

[hoyden]

I did that yesterday there was a 2° difference - remote one reads 27F and the other one @ 25F (post #155 so many posts! Wow!)

It's now 1:40pm and they seem more normal - back one reads 32° and door reads 38F.
Just now turned fridge knob to 4 (from 4.5) !

I haven't been able to have it lower than 6 to keep food in safe temp range since I got this camper!

 

[hoyden]

New battery separator is installed. I'll leave tomorrow and not be plugged in to shore power and then I'll find out if that all is now working properly. What a hassle this has all been!

I gotta figure out where I'm gonna go next (from Albuquerque)....

 

[PaulT]

New battery separator is installed. I'll leave tomorrow and not be plugged in to shore power and then I'll find out if that all is now working properly. What a hassle this has all been!

I gotta figure out where I'm gonna go next (from Albuquerque)....

Hassle? Sure. But what a highly educated user you have become as a result of all the trials & tribulations.

You will be able to solve most any power or fridge related problem while boondocking.
That's a good thing.

Enjoy your trip. Take careful & detailed notes. Life is an exam.

Paul

 

[hoyden]

I'M DAMN NEAR AN EXPERT NOW!
.
.
.

(thanks to y'all and my on the ground friends!)

 

[hoyden]

I posted a new Trip Report update here: http://www.wanderthewest.com/forum/topic/16758-no-destination-finding-home-tour/?p=203908